In this review article, the uses of organic polymers to make photovoltaic cells have been discussed. The focus is mainly on discussing organic polymer based photovoltaic (OPVs) solar cells, the development of new device technologies and donor polymers that are being researched on. The recent development in this field has led to improved OPV performances with power conversion efficiencies as phenomenal as 9%. However for commercial application of this kind of OPVs, an improved device structure and cost effective processing methods are required. This article reports the polymer design criteria, energy level matching, nano-morphing of polymer/acceptor blend films and local dipole moments of the polymer chains that have been developed in the research that took place over the past 4 years. We emphasize the importance of developing new methods for designing polymers with improved physical properties and development of new technologies to fully understand the fundamentals of OPV mechanisms, which will help improve the power conversion efficiency of the OPV.
Ndola 10 mw biomass power project feasibility study (in partnership with eep)Business Finland
The feasibility study found that a 10MW biomass power plant fueled by wood waste from local timber operations in Ndola, Zambia is feasible. A plant using steam turbine technology could be sustained from available waste and have a capacity of 7MW. Additional biomass sources could increase capacity to 10MW. Challenges include finalizing land acquisition, securing a firm feedstock supply, and obtaining a tariff that makes the plant economically viable. Next steps are to complete the land deal, environmental review, engage potential heat and electricity customers, and arrange project financing.
Performance Analysis of Autonomous Hybrid Distributed Generation Based on Typ...ijtsrd
It is undeniable fact that even though fossil fuels are likely more to fulfill the requirements of energy, the rare of natural resources and their harmful contents for the environment have directed people to search for new energy sources like renewable resources such as hydropower, biomass, wind, solar and other types of clean energy. In order to highlight the proposed methodology, PV Diesel generator DG with battery energy system BESS based on two typical control strategies, load following LF control strategy and cycle charging CC control strategy, have been analyzed by using HOMER Software to supply the Makyiyay village which is located at 22.02 north latitude and 96.56 east longitude in the Naungkhyo Township, Southern Shan State in Myanmar. The yearly average solar radiation of that area is 4.895kWh m2 day and it is very important to prepare a proper load data to meet the current situation of the target village which has 45 household numbers. By calculating the total load demand, the peak demand of that proposed village is 34kW. The fractions of energy production from PV array and diesel generator of the proposed PV Diesel BESS hybrid system using LF control strategy are 60 and 40 to meet the demand. Moreover, the proposed hybrid system based on LF control strategy provides the lowest TNPC, COE and carbon emission than the hybrid system based on CC control strategy according to the evaluation results. In contrast, the analysis of evaluation results shows that the PV Diesel ESS based on LF control choice is more economically possible than that system based on CC control. Phyu Phyu Win | Zin Mar "Performance Analysis of Autonomous Hybrid Distributed Generation Based on Typical Control Strategies for Rural Electrification in Myanmar" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26695.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/26695/performance-analysis-of-autonomous-hybrid-distributed-generation-based-on-typical-control-strategies-for-rural-electrification-in-myanmar/phyu-phyu-win
Flinders Island Isolated Power System (IPS) Connect 2016 S KILMETE PUCjames hamilton
The Federated States of Micronesia (FSM) is a grouping of 607 small islands in the Western Pacific about 2,500 miles southwest of Hawaii, lying just above the Equator. Generally speaking, FSM comprises what is known as the Eastern and Western Caroline Islands. While the country's total land area amounts to only 270.8 square miles, it occupies more than one million square miles of the Pacific ocean, and ranges 1,700 miles from East (Kosrae) to West (Yap)- Each of the four States centers around one or more "high islands." and all but Kosrae include numerous atolls.
Chuuk State has a total land area of 492 square miles and includes seven major island groups. Pohnpei State has 133.4 square miles of land area, of which 130 is accounted for by Pohnpei island, the largest in FSM. Yap State is made up of 4 large islands, 7 small islands and 134 atolls, with a total land area of 45.6 square miles- Kosrae is essentially one high island of 42.3 square miles.
FSM enjoys a tropical climate, with relatively even, warm temperatures throughout the year. Rainfall is generally plentiful, and Pohnpei reputedly is one of the wettest places on Earth, with up to 330 inches of rain per year.
Powering mobile network with green energyAbu Yohannan
This document discusses optimizing mobile networks through the use of green energy sources. It begins with an introduction to the growth of energy consumption and carbon footprints in mobile networks. It then discusses green energy sources like wind, solar, and hydropower. The document outlines different models for powering mobile networks through green energy, including off-grid and on-grid configurations. It proposes optimizing resource management and scheduling to maximize the utilization of variable green energy supplies. The goal is to reduce reliance on power grids and lower the carbon footprint of mobile networks.
The Vanadium Redox Flow Battery and South Africa's Export OpportunityBushveld Energy
Bushveld Energy's presentation at the South Africa Energy Storage Conference (28 November 2017), covering:
• An overview the VRFB technology, including deployment, design, benefits in battery performance, safety and sustainability;
• South Africa-specific business cases for VRFB technology;
• Arguments for why South Africa is uniquely positioned to benefit in the global success of VRFBs.
The document discusses incorporating microgrid technology with rooftop solar PV deployment to enhance energy economics. It identifies factors that cause energy losses in the existing distribution system, such as inefficient equipment and conversion losses. A hybrid microgrid is proposed to effectively manage the distribution system and efficiently utilize solar power and storage. Comparisons are presented based on energy savings, payback period calculations, and CO2 emission reductions to prove the effectiveness of the proposed method.
This document summarizes the status of building integrated photovoltaic (BIPV) applications in Malaysia. It discusses that between 1998-2002, Malaysia successfully completed several pilot BIPV projects totaling over 400kWp installed across various buildings. Key lessons learned included addressing issues like roof leakage and lightning protection that are prevalent in the tropical climate. While BIPV system costs in Malaysia have decreased significantly, costs remain relatively high compared to other countries due to components still being imported and lack of local market. The government is now working to further develop BIPV through new programs and a national steering committee on renewable technologies.
By Mr. Irish Pereira The current and expected usage of redox flow batteries across the World.
Includes usage of redox batteries in power generation sectors, including market trends.
Ndola 10 mw biomass power project feasibility study (in partnership with eep)Business Finland
The feasibility study found that a 10MW biomass power plant fueled by wood waste from local timber operations in Ndola, Zambia is feasible. A plant using steam turbine technology could be sustained from available waste and have a capacity of 7MW. Additional biomass sources could increase capacity to 10MW. Challenges include finalizing land acquisition, securing a firm feedstock supply, and obtaining a tariff that makes the plant economically viable. Next steps are to complete the land deal, environmental review, engage potential heat and electricity customers, and arrange project financing.
Performance Analysis of Autonomous Hybrid Distributed Generation Based on Typ...ijtsrd
It is undeniable fact that even though fossil fuels are likely more to fulfill the requirements of energy, the rare of natural resources and their harmful contents for the environment have directed people to search for new energy sources like renewable resources such as hydropower, biomass, wind, solar and other types of clean energy. In order to highlight the proposed methodology, PV Diesel generator DG with battery energy system BESS based on two typical control strategies, load following LF control strategy and cycle charging CC control strategy, have been analyzed by using HOMER Software to supply the Makyiyay village which is located at 22.02 north latitude and 96.56 east longitude in the Naungkhyo Township, Southern Shan State in Myanmar. The yearly average solar radiation of that area is 4.895kWh m2 day and it is very important to prepare a proper load data to meet the current situation of the target village which has 45 household numbers. By calculating the total load demand, the peak demand of that proposed village is 34kW. The fractions of energy production from PV array and diesel generator of the proposed PV Diesel BESS hybrid system using LF control strategy are 60 and 40 to meet the demand. Moreover, the proposed hybrid system based on LF control strategy provides the lowest TNPC, COE and carbon emission than the hybrid system based on CC control strategy according to the evaluation results. In contrast, the analysis of evaluation results shows that the PV Diesel ESS based on LF control choice is more economically possible than that system based on CC control. Phyu Phyu Win | Zin Mar "Performance Analysis of Autonomous Hybrid Distributed Generation Based on Typical Control Strategies for Rural Electrification in Myanmar" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26695.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/26695/performance-analysis-of-autonomous-hybrid-distributed-generation-based-on-typical-control-strategies-for-rural-electrification-in-myanmar/phyu-phyu-win
Flinders Island Isolated Power System (IPS) Connect 2016 S KILMETE PUCjames hamilton
The Federated States of Micronesia (FSM) is a grouping of 607 small islands in the Western Pacific about 2,500 miles southwest of Hawaii, lying just above the Equator. Generally speaking, FSM comprises what is known as the Eastern and Western Caroline Islands. While the country's total land area amounts to only 270.8 square miles, it occupies more than one million square miles of the Pacific ocean, and ranges 1,700 miles from East (Kosrae) to West (Yap)- Each of the four States centers around one or more "high islands." and all but Kosrae include numerous atolls.
Chuuk State has a total land area of 492 square miles and includes seven major island groups. Pohnpei State has 133.4 square miles of land area, of which 130 is accounted for by Pohnpei island, the largest in FSM. Yap State is made up of 4 large islands, 7 small islands and 134 atolls, with a total land area of 45.6 square miles- Kosrae is essentially one high island of 42.3 square miles.
FSM enjoys a tropical climate, with relatively even, warm temperatures throughout the year. Rainfall is generally plentiful, and Pohnpei reputedly is one of the wettest places on Earth, with up to 330 inches of rain per year.
Powering mobile network with green energyAbu Yohannan
This document discusses optimizing mobile networks through the use of green energy sources. It begins with an introduction to the growth of energy consumption and carbon footprints in mobile networks. It then discusses green energy sources like wind, solar, and hydropower. The document outlines different models for powering mobile networks through green energy, including off-grid and on-grid configurations. It proposes optimizing resource management and scheduling to maximize the utilization of variable green energy supplies. The goal is to reduce reliance on power grids and lower the carbon footprint of mobile networks.
The Vanadium Redox Flow Battery and South Africa's Export OpportunityBushveld Energy
Bushveld Energy's presentation at the South Africa Energy Storage Conference (28 November 2017), covering:
• An overview the VRFB technology, including deployment, design, benefits in battery performance, safety and sustainability;
• South Africa-specific business cases for VRFB technology;
• Arguments for why South Africa is uniquely positioned to benefit in the global success of VRFBs.
The document discusses incorporating microgrid technology with rooftop solar PV deployment to enhance energy economics. It identifies factors that cause energy losses in the existing distribution system, such as inefficient equipment and conversion losses. A hybrid microgrid is proposed to effectively manage the distribution system and efficiently utilize solar power and storage. Comparisons are presented based on energy savings, payback period calculations, and CO2 emission reductions to prove the effectiveness of the proposed method.
This document summarizes the status of building integrated photovoltaic (BIPV) applications in Malaysia. It discusses that between 1998-2002, Malaysia successfully completed several pilot BIPV projects totaling over 400kWp installed across various buildings. Key lessons learned included addressing issues like roof leakage and lightning protection that are prevalent in the tropical climate. While BIPV system costs in Malaysia have decreased significantly, costs remain relatively high compared to other countries due to components still being imported and lack of local market. The government is now working to further develop BIPV through new programs and a national steering committee on renewable technologies.
By Mr. Irish Pereira The current and expected usage of redox flow batteries across the World.
Includes usage of redox batteries in power generation sectors, including market trends.
The document summarizes Malaysia's renewable energy initiatives and policies. It discusses (1) Malaysia's targets for renewable energy capacity from the 8th to 10th Malaysia Plans; (2) the various support mechanisms and promotion mechanisms established including the Small Renewable Energy Power Programme, Biomass Power Generation Project, and Malaysia Building Integrated Photovoltaic Project; and (3) the key issues affecting renewable energy development and the strategic thrusts of the new National Renewable Energy Policy approved in 2010, including establishing a conducive business environment, developing human capital, renewable energy research and development, enacting renewable energy legislation, and implementing a feed-in tariff program and renewable energy fund.
Peripheral interface controller-based maximum power point tracking algorithm ...TELKOMNIKA JOURNAL
A method of developing a maximum power point tracking (MPPT) algorithm for photovoltaic (PV) utilizing a peripheral interface controller (PIC) is presented in this paper. The efficiency and adequacy of a PV depend on the temperature and the exposed position to the sun. Thus, there is an optimum point at which the operating power is at maximum. The goal is to operate the PV module at this point (MPP). It can be accomplished by using the MPPT algorithm designed with a DC-DC boost converter. The boost converter, MPPT circuit, PIC18F4550 microcontroller and PV panel are the main components used in this design. The current and voltage produced by the solar panel are observed continuously by a closed-loop control system. The microcontroller-based control system adjusts the duty cycle of the converter to extract the maximum power. With a DC input voltage of 15 V, the boost converter is capable of generating an output voltage of an approximately 60 Vdc at a maximum power of 213.42 W with minimum voltage ripple as compared to 84 W without the MPPT. It proved the effectiveness of the developed algorithm.
Renewable Energy (RE) penetration is a new phenomenon in power systems. In the advent of high penetration of RE in the systems, several issues have to be addressed especially when it involves the stability and flexibility of the power systems. Battery Energy Storage System (BESS) has gained popularity due to its capability to store energy and to serve multiple purposes in solving various power system concerns. Additionally, several BESS can be combined to operate as Virtual Power Plant (VPP). This study will involve the design and implementation of BESS for five potential customer sites for the demonstration project and to be possibly integrated into one VPP system. The study is expected to demonstrate bill savings to the customers with BESS due to peak demand reduction and energy arbitrage savings. Renewable Energy (RE) penetration is a new phenomenon in power systems. In the advent of high penetration of RE in the systems, several issues have to be addressed especially when it involves the stability and flexibility of the power systems. Battery Energy Storage System (BESS) has gained popularity due to its capability to store energy and to serve multiple purposes in solving various power system concerns. Additionally, several BESS can be combined to operate as Virtual Power Plant (VPP). This study will involve the design and implementation of BESS for five potential customer sites for the demonstration project and to be possibly integrated into one VPP system. The study is expected to demonstrate bill savings to the customers with BESS due to peak demand reduction and energy arbitrage savings.
Harvesting in electric vehicles: Combining multiple power tracking and fuel-c...IJECEIAES
This document summarizes a research article that proposes a power electronic platform and energy management strategy (EMS) to harvest energy from multiple sources in electric vehicles. The platform allows simultaneous operation of sources like solar panels, fuel cells, energy-generating dampers, and others. The EMS aims to minimize degradation of the battery bank and fuel cell by filtering current transients and ensuring sources operate at their maximum power points. A mathematical model of the platform is presented and stability analysis was performed. Numerical, hardware-in-the-loop, and experimental validations supported the effectiveness of the approach.
Design and performance analysis of PV grid-tied system with energy storage sy...IJECEIAES
This document summarizes the design and performance analysis of a photovoltaic (PV) grid-tied system with an energy storage system. The system consists of an 8 kW solar array, 600 V maximum power point tracking charging controller, 7.6 kW grid-tied inverter, and 600 Ah battery bank. Simulations of the system are performed using the System Advisor Model software to analyze the system's performance. The results show the solar panels provide power during the day while the batteries provide power in the evenings and help reduce peak loads and electric bills through peak shaving. The battery can be coupled to the grid through AC or DC modes and the system ensures power supply even when the grid goes down by using the batteries and
The document analyzes the current energy consumption patterns and forecasts the future energy demand of Jaya Container Terminal (JCT) in Sri Lanka by 2020. It models the current energy use using LEAP software and evaluates the per TEU energy consumption for different container types handled by JCT. It then forecasts JCT's energy demand by 2020 based on projections for container throughput. Finally, it analyzes potential demand side management options to reduce energy costs and consumption at JCT in the future.
IRJET- A Review on Designing of 100KV Grid Power using Hybrid ParametersIRJET Journal
This document reviews the design of a 100kV grid power system using hybrid wind and solar energy sources. It discusses using a converter and inverter to integrate the wind and solar energy inputs and provide high quality AC power to the grid. The aim is to maximize energy extraction from both sources and maintain a stable output voltage. Several previous studies on hybrid renewable energy systems, multilevel inverters, and maximum power point tracking algorithms are also summarized to provide relevant background.
This document discusses options for existing U.S. coal-fired power plants facing costs for carbon dioxide emissions, including continuing operations, switching fuels, retrofitting with carbon capture and sequestration, repowering with advanced coal technology incorporating CCS, and refurbishing to improve efficiency. The authors modified the National Energy Modeling System to evaluate the economics of retrofitting, repowering, and refurbishing options compared to other strategies. Under a $45-60/MTCO2e carbon price, the estimated market for retrofitting existing plants with near-commercial CCS technology is around 100 GW, while a similar market exists for repowering with not-yet-commercialized technologies. Refurbishing can
Flinders Island Isolated Power System (IPS) Connect 2016 R ROCHELEAU HNEIjames hamilton
Although the Hawaiian Islands are blessed with an abundance of renewable energy sources including excellent solar and wind resources, and have the nation’s most aggressive renewable energy standards, the state still rely heavily on fossil fuels for electricity generation. With isolated (unconnected) island grids and sparse systems on some islands, integration of the intermittent renewable generation systems has been challenging. The Hawaii Natural Energy Institute (HNEI) at the University of Hawaii has initiated an integrated effort involving modeling, testing, and demonstration to identify and validate pathways to higher renewable integration. In this talk, I will discuss the analysis being used to identify strategic paths forward and will describe several projects currently underway including the Maui Smart Grid Demonstration Project, the Smart Grid Inverter Project and several grid-scale battery energy storage projects.
Richard Rocheleau (PhD, Chemical Engineering, University of DE), has over 35 years of experience in renewable energy, with an emphasis in the areas of photovoltaics, hydrogen fuel cells, and energy systems. Dr. Rocheleau joined the faculty of the Hawaii Natural Energy Institute at the University of Hawaii in 1988 and was appointed Director in 2000. Under his direction, the Institute is leading the development of public‐private partnerships focused on the development, testing and integration of alternative energy technologies into the electrical grid. HNEI has major funding from the US Department of Energy and the Office of Naval Research. Dr. Rocheleau was also successful in positioning the Institute to receive a portion of the ‘barrel tax’, established by the Hawaii State Legislature supporting studies for integration of renewable energy technologies into the grid intended to assist the state to meet its aggressive renewable energy portfolio goals.
Electric Power Management for a Grid Connected Renewable Energy Sourcestheijes
This document summarizes a research paper on electric power management for a grid-connected renewable energy system combining photovoltaic (PV) arrays and proton exchange membrane fuel cells (PEMFC). The hybrid system uses two operation modes: unit-power control (UPC) mode regulates the hybrid source output to a reference power while variations in load demand are compensated by the main grid; feeder-flow control (FFC) mode regulates the feeder flow to a constant while the hybrid source picks up extra load demand. A maximum power point tracking (MPPT) technique is used to optimize PV output power. The fuel cells provide a controllable source to overcome the intermittent nature of solar power.
A Comparative Study for Different Sizing of Solar PV System under Net Energy ...journalBEEI
Malaysia has moved forward by promoting the use of renewable energy such as solar PV to the public to reduce dependency on fossil fuel-based energy resources. Due to the concern on high electricity bill, Universiti Malaysia Perlis (UniMAP) is keen to install solar PV system as an initiative for energy saving program to its buildings. The objective of this paper is to technically and economically evaluate the different sizing of solar PV system for university buildings under the Net Energy Metering (NEM) scheme. The study involves gathering of solar energy resource information, daily load profile of the buildings, sizing PV array together with grid-connected inverters and the simulation of the designed system using PVsyst software. Based on the results obtained, the amount of solar energy generated and used by the load per year is between 5.10% and 20.20% from the total annual load demand. Almost all solar energy generated from the system will be self-consumed by the loads. In terms of profit gained, the university could reduce its electricity bill approximately between a quarter to one million ringgit per annum depending on the sizing capacity. Beneficially, the university could contribute to the environmental conservation by avoiding up to 2,000 tons of CO2 emission per year.
IRJET- Identification and Validation of Various Factors and Purposes Targ...IRJET Journal
This document discusses research on factors and purposes that can help advance development of microbial fuel cells (MFCs). MFCs use microbes to convert organic matter into electricity and have potential as a renewable energy source. The document identifies several key factors and purposes of MFC research, including improving power output, using various substrates, integrating with plant cells, and applying MFCs to wastewater treatment. It also reviews various existing MFC designs and materials. The overall goal is to better understand how to optimize MFC technology for renewable energy and environmental applications.
Flinders Island Isolated Power System (IPS) Connect 2016 H KUMAR SOLOMON POWERjames hamilton
The four key challenges for Solomon Power in the future are effective and efficient delivery of the SBD 1 Billion capital programme, development and sustenance of human capital, increasing the footprint of the electricity network and to offer electricity at lower prices. Solomon Power are conscious of the high cost of electricity in Solomon Islands due to our heavy reliance on diesel and are therefore actively working with all our stakeholders to pursue initiatives to bring down the price of electricity. We hope the renewable energy proposals on the table, on completion, will assist Solomon Power to reduce the price of electricity.This includes the recent commisioning of the 1MW Hendeson solar farm, 150kW Buala mini-Hydro and upgrade to he Honiara and Lungga power stations.
Hemant Kumar is a Chartered Electrical Engineer with more than 28 years of experience in the Power Industry in Australia, New Zealand and in the South Pacific. He has held senior management roles while working for electricity distribution, transmission and generation utilities. His roles included Team leadership, Planning Manager/Engineer, Network Development Manager, Standards Manager, Design Manager, Project Manager, and Contracts Manager/Engineer. He has led an amalgamation of several design standards. He has been responsible for development of asset management plans, network planning, and optimization and capital expenditure programs. He also has several years of electricity network management experience including planning, operational, development of business case to the board and development of asset management plans.
A battery charging system & appended zcs (pwm) resonant converter dc dc buck ...hunypink
This paper presents technique for battery charger to achieve efficient performance in charging shaping,
minimum low switching losses and reduction in circuit volume .The operation of circuit charger is switched
with the technique of zero-current-switching, resonant components and append the topology of dc-dc buck.
The proposed novel dc-dc battery charger has advantages with the simplicity, low cost, high efficiency and
with the behaviour of easy control under the ZCS condition accordingly reducing the switching losses. The
detailed study of operating principle and design consideration is performed. A short survey of battery
charging system, capacity demand & its topologies is also presented. In order to compute LC resonant pair
values in conventional converter, the method of characteristic curve is used and electric function equations
are derived from the prototype configuration. The efficient performance of charging shaping is confirmed
through the practical examines and verification of the results is revealed by the MATLAB simulation. The
efficiency is ensured about 89% which is substantially considered being satisfactory performance as
achieved in this paper.
A BATTERY CHARGING SYSTEM & APPENDED ZCS (PWM) RESONANT CONVERTER DC-DC BUCK:...ELELIJ
This document summarizes a research paper that proposes a novel battery charging system using a zero-current switching pulse width modulation resonant converter DC-DC buck topology. The system aims to achieve high charging efficiency with minimal switching losses and reduced circuit volume. It operates by switching the circuit with zero-current switching and resonant components to reduce losses and switching stress. The paper analyzes the operating principle and design of the proposed system through 5 modes of operation. Simulation results show the system achieves around 89% charging efficiency, demonstrating satisfactory performance.
Presentation from 2018 Africa Energy Forum on the applications of flow batteries in Africa. The document focuses on vanadium redox flow battery (VRFB) technology and looks at the true hybrid solar + storage micro-grid and utility use cases in particular.
A review of hybrid solar pv and wind energy system paperRanjit Singh
The document provides a review of hybrid solar photovoltaic (PV) and wind energy systems. It discusses how combining solar and wind power can provide more reliable energy generation by offsetting the intermittency of each source. It reviews the challenges of integrating such hybrid systems into electric grids or using them for standalone power, as well as potential solutions like optimal sizing, power electronics configurations, and advanced control systems. The document summarizes research on both grid-connected and standalone hybrid solar-wind systems.
An Efficient Elliptic Curve Cryptography Arithmetic Using Nikhilam Multiplica...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
In-vitro Interaction of αB-Crystallin on Serum Amyloid A and Serum Amyloid A ...theijes
The interactions of SAA and SAA protofibrils with protecting role of alphaB-Crystallin with hepta 1-6 cells of the mouse are dealt with in detail to study the binding of SAA protofibrils in various conditions. Specifically, interaction of serum amyloid A fibrils with a cell surface binding site/receptor might alter the local environment to cause cellular dysfunction and to be more favorable for amyloid formation and prevention with alphaB-Crystallin. This is important in relation to the activity of membrane proteins, because losing the activity of such systems will ultimately lead to malfunction or death of the cell. The interactions of Serum Amyloid A (SAA) and Serum Amyloid A protofibrils with hepta 1-6 cells of the mouse are dealt with in detail to study the binding of SAA protofibrils in various onditions. The induced fluorescence, induced circular dichroism, FACScan and MTT assay results have shown the SAA and SAA prototfibrils binding and cell toxicity with the hepta 1-6 cells with different concentrations of alphaB-Crystallin 0.15-15 nM. Specifically, cells were incubated with 1.25-6.25 M SAA-FITC and SAA protofibrils-FITC assayed. The 50% viable hepta 1-6 cells at 4–6 M with an LD50 of 3.5 M. The interaction of serum amyloid A fibrils with a cell surface binding site/receptor might alter the local environment to cause cellular dysfunction and to be more favorable for amyloid formation. In the present study, concluding that the SAA fibrils and SAA protein binding and cell cytotoxicity was reduced in the presence of alphaB-Crystallin.
The document summarizes Malaysia's renewable energy initiatives and policies. It discusses (1) Malaysia's targets for renewable energy capacity from the 8th to 10th Malaysia Plans; (2) the various support mechanisms and promotion mechanisms established including the Small Renewable Energy Power Programme, Biomass Power Generation Project, and Malaysia Building Integrated Photovoltaic Project; and (3) the key issues affecting renewable energy development and the strategic thrusts of the new National Renewable Energy Policy approved in 2010, including establishing a conducive business environment, developing human capital, renewable energy research and development, enacting renewable energy legislation, and implementing a feed-in tariff program and renewable energy fund.
Peripheral interface controller-based maximum power point tracking algorithm ...TELKOMNIKA JOURNAL
A method of developing a maximum power point tracking (MPPT) algorithm for photovoltaic (PV) utilizing a peripheral interface controller (PIC) is presented in this paper. The efficiency and adequacy of a PV depend on the temperature and the exposed position to the sun. Thus, there is an optimum point at which the operating power is at maximum. The goal is to operate the PV module at this point (MPP). It can be accomplished by using the MPPT algorithm designed with a DC-DC boost converter. The boost converter, MPPT circuit, PIC18F4550 microcontroller and PV panel are the main components used in this design. The current and voltage produced by the solar panel are observed continuously by a closed-loop control system. The microcontroller-based control system adjusts the duty cycle of the converter to extract the maximum power. With a DC input voltage of 15 V, the boost converter is capable of generating an output voltage of an approximately 60 Vdc at a maximum power of 213.42 W with minimum voltage ripple as compared to 84 W without the MPPT. It proved the effectiveness of the developed algorithm.
Renewable Energy (RE) penetration is a new phenomenon in power systems. In the advent of high penetration of RE in the systems, several issues have to be addressed especially when it involves the stability and flexibility of the power systems. Battery Energy Storage System (BESS) has gained popularity due to its capability to store energy and to serve multiple purposes in solving various power system concerns. Additionally, several BESS can be combined to operate as Virtual Power Plant (VPP). This study will involve the design and implementation of BESS for five potential customer sites for the demonstration project and to be possibly integrated into one VPP system. The study is expected to demonstrate bill savings to the customers with BESS due to peak demand reduction and energy arbitrage savings. Renewable Energy (RE) penetration is a new phenomenon in power systems. In the advent of high penetration of RE in the systems, several issues have to be addressed especially when it involves the stability and flexibility of the power systems. Battery Energy Storage System (BESS) has gained popularity due to its capability to store energy and to serve multiple purposes in solving various power system concerns. Additionally, several BESS can be combined to operate as Virtual Power Plant (VPP). This study will involve the design and implementation of BESS for five potential customer sites for the demonstration project and to be possibly integrated into one VPP system. The study is expected to demonstrate bill savings to the customers with BESS due to peak demand reduction and energy arbitrage savings.
Harvesting in electric vehicles: Combining multiple power tracking and fuel-c...IJECEIAES
This document summarizes a research article that proposes a power electronic platform and energy management strategy (EMS) to harvest energy from multiple sources in electric vehicles. The platform allows simultaneous operation of sources like solar panels, fuel cells, energy-generating dampers, and others. The EMS aims to minimize degradation of the battery bank and fuel cell by filtering current transients and ensuring sources operate at their maximum power points. A mathematical model of the platform is presented and stability analysis was performed. Numerical, hardware-in-the-loop, and experimental validations supported the effectiveness of the approach.
Design and performance analysis of PV grid-tied system with energy storage sy...IJECEIAES
This document summarizes the design and performance analysis of a photovoltaic (PV) grid-tied system with an energy storage system. The system consists of an 8 kW solar array, 600 V maximum power point tracking charging controller, 7.6 kW grid-tied inverter, and 600 Ah battery bank. Simulations of the system are performed using the System Advisor Model software to analyze the system's performance. The results show the solar panels provide power during the day while the batteries provide power in the evenings and help reduce peak loads and electric bills through peak shaving. The battery can be coupled to the grid through AC or DC modes and the system ensures power supply even when the grid goes down by using the batteries and
The document analyzes the current energy consumption patterns and forecasts the future energy demand of Jaya Container Terminal (JCT) in Sri Lanka by 2020. It models the current energy use using LEAP software and evaluates the per TEU energy consumption for different container types handled by JCT. It then forecasts JCT's energy demand by 2020 based on projections for container throughput. Finally, it analyzes potential demand side management options to reduce energy costs and consumption at JCT in the future.
IRJET- A Review on Designing of 100KV Grid Power using Hybrid ParametersIRJET Journal
This document reviews the design of a 100kV grid power system using hybrid wind and solar energy sources. It discusses using a converter and inverter to integrate the wind and solar energy inputs and provide high quality AC power to the grid. The aim is to maximize energy extraction from both sources and maintain a stable output voltage. Several previous studies on hybrid renewable energy systems, multilevel inverters, and maximum power point tracking algorithms are also summarized to provide relevant background.
This document discusses options for existing U.S. coal-fired power plants facing costs for carbon dioxide emissions, including continuing operations, switching fuels, retrofitting with carbon capture and sequestration, repowering with advanced coal technology incorporating CCS, and refurbishing to improve efficiency. The authors modified the National Energy Modeling System to evaluate the economics of retrofitting, repowering, and refurbishing options compared to other strategies. Under a $45-60/MTCO2e carbon price, the estimated market for retrofitting existing plants with near-commercial CCS technology is around 100 GW, while a similar market exists for repowering with not-yet-commercialized technologies. Refurbishing can
Flinders Island Isolated Power System (IPS) Connect 2016 R ROCHELEAU HNEIjames hamilton
Although the Hawaiian Islands are blessed with an abundance of renewable energy sources including excellent solar and wind resources, and have the nation’s most aggressive renewable energy standards, the state still rely heavily on fossil fuels for electricity generation. With isolated (unconnected) island grids and sparse systems on some islands, integration of the intermittent renewable generation systems has been challenging. The Hawaii Natural Energy Institute (HNEI) at the University of Hawaii has initiated an integrated effort involving modeling, testing, and demonstration to identify and validate pathways to higher renewable integration. In this talk, I will discuss the analysis being used to identify strategic paths forward and will describe several projects currently underway including the Maui Smart Grid Demonstration Project, the Smart Grid Inverter Project and several grid-scale battery energy storage projects.
Richard Rocheleau (PhD, Chemical Engineering, University of DE), has over 35 years of experience in renewable energy, with an emphasis in the areas of photovoltaics, hydrogen fuel cells, and energy systems. Dr. Rocheleau joined the faculty of the Hawaii Natural Energy Institute at the University of Hawaii in 1988 and was appointed Director in 2000. Under his direction, the Institute is leading the development of public‐private partnerships focused on the development, testing and integration of alternative energy technologies into the electrical grid. HNEI has major funding from the US Department of Energy and the Office of Naval Research. Dr. Rocheleau was also successful in positioning the Institute to receive a portion of the ‘barrel tax’, established by the Hawaii State Legislature supporting studies for integration of renewable energy technologies into the grid intended to assist the state to meet its aggressive renewable energy portfolio goals.
Electric Power Management for a Grid Connected Renewable Energy Sourcestheijes
This document summarizes a research paper on electric power management for a grid-connected renewable energy system combining photovoltaic (PV) arrays and proton exchange membrane fuel cells (PEMFC). The hybrid system uses two operation modes: unit-power control (UPC) mode regulates the hybrid source output to a reference power while variations in load demand are compensated by the main grid; feeder-flow control (FFC) mode regulates the feeder flow to a constant while the hybrid source picks up extra load demand. A maximum power point tracking (MPPT) technique is used to optimize PV output power. The fuel cells provide a controllable source to overcome the intermittent nature of solar power.
A Comparative Study for Different Sizing of Solar PV System under Net Energy ...journalBEEI
Malaysia has moved forward by promoting the use of renewable energy such as solar PV to the public to reduce dependency on fossil fuel-based energy resources. Due to the concern on high electricity bill, Universiti Malaysia Perlis (UniMAP) is keen to install solar PV system as an initiative for energy saving program to its buildings. The objective of this paper is to technically and economically evaluate the different sizing of solar PV system for university buildings under the Net Energy Metering (NEM) scheme. The study involves gathering of solar energy resource information, daily load profile of the buildings, sizing PV array together with grid-connected inverters and the simulation of the designed system using PVsyst software. Based on the results obtained, the amount of solar energy generated and used by the load per year is between 5.10% and 20.20% from the total annual load demand. Almost all solar energy generated from the system will be self-consumed by the loads. In terms of profit gained, the university could reduce its electricity bill approximately between a quarter to one million ringgit per annum depending on the sizing capacity. Beneficially, the university could contribute to the environmental conservation by avoiding up to 2,000 tons of CO2 emission per year.
IRJET- Identification and Validation of Various Factors and Purposes Targ...IRJET Journal
This document discusses research on factors and purposes that can help advance development of microbial fuel cells (MFCs). MFCs use microbes to convert organic matter into electricity and have potential as a renewable energy source. The document identifies several key factors and purposes of MFC research, including improving power output, using various substrates, integrating with plant cells, and applying MFCs to wastewater treatment. It also reviews various existing MFC designs and materials. The overall goal is to better understand how to optimize MFC technology for renewable energy and environmental applications.
Flinders Island Isolated Power System (IPS) Connect 2016 H KUMAR SOLOMON POWERjames hamilton
The four key challenges for Solomon Power in the future are effective and efficient delivery of the SBD 1 Billion capital programme, development and sustenance of human capital, increasing the footprint of the electricity network and to offer electricity at lower prices. Solomon Power are conscious of the high cost of electricity in Solomon Islands due to our heavy reliance on diesel and are therefore actively working with all our stakeholders to pursue initiatives to bring down the price of electricity. We hope the renewable energy proposals on the table, on completion, will assist Solomon Power to reduce the price of electricity.This includes the recent commisioning of the 1MW Hendeson solar farm, 150kW Buala mini-Hydro and upgrade to he Honiara and Lungga power stations.
Hemant Kumar is a Chartered Electrical Engineer with more than 28 years of experience in the Power Industry in Australia, New Zealand and in the South Pacific. He has held senior management roles while working for electricity distribution, transmission and generation utilities. His roles included Team leadership, Planning Manager/Engineer, Network Development Manager, Standards Manager, Design Manager, Project Manager, and Contracts Manager/Engineer. He has led an amalgamation of several design standards. He has been responsible for development of asset management plans, network planning, and optimization and capital expenditure programs. He also has several years of electricity network management experience including planning, operational, development of business case to the board and development of asset management plans.
A battery charging system & appended zcs (pwm) resonant converter dc dc buck ...hunypink
This paper presents technique for battery charger to achieve efficient performance in charging shaping,
minimum low switching losses and reduction in circuit volume .The operation of circuit charger is switched
with the technique of zero-current-switching, resonant components and append the topology of dc-dc buck.
The proposed novel dc-dc battery charger has advantages with the simplicity, low cost, high efficiency and
with the behaviour of easy control under the ZCS condition accordingly reducing the switching losses. The
detailed study of operating principle and design consideration is performed. A short survey of battery
charging system, capacity demand & its topologies is also presented. In order to compute LC resonant pair
values in conventional converter, the method of characteristic curve is used and electric function equations
are derived from the prototype configuration. The efficient performance of charging shaping is confirmed
through the practical examines and verification of the results is revealed by the MATLAB simulation. The
efficiency is ensured about 89% which is substantially considered being satisfactory performance as
achieved in this paper.
A BATTERY CHARGING SYSTEM & APPENDED ZCS (PWM) RESONANT CONVERTER DC-DC BUCK:...ELELIJ
This document summarizes a research paper that proposes a novel battery charging system using a zero-current switching pulse width modulation resonant converter DC-DC buck topology. The system aims to achieve high charging efficiency with minimal switching losses and reduced circuit volume. It operates by switching the circuit with zero-current switching and resonant components to reduce losses and switching stress. The paper analyzes the operating principle and design of the proposed system through 5 modes of operation. Simulation results show the system achieves around 89% charging efficiency, demonstrating satisfactory performance.
Presentation from 2018 Africa Energy Forum on the applications of flow batteries in Africa. The document focuses on vanadium redox flow battery (VRFB) technology and looks at the true hybrid solar + storage micro-grid and utility use cases in particular.
A review of hybrid solar pv and wind energy system paperRanjit Singh
The document provides a review of hybrid solar photovoltaic (PV) and wind energy systems. It discusses how combining solar and wind power can provide more reliable energy generation by offsetting the intermittency of each source. It reviews the challenges of integrating such hybrid systems into electric grids or using them for standalone power, as well as potential solutions like optimal sizing, power electronics configurations, and advanced control systems. The document summarizes research on both grid-connected and standalone hybrid solar-wind systems.
An Efficient Elliptic Curve Cryptography Arithmetic Using Nikhilam Multiplica...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
In-vitro Interaction of αB-Crystallin on Serum Amyloid A and Serum Amyloid A ...theijes
The interactions of SAA and SAA protofibrils with protecting role of alphaB-Crystallin with hepta 1-6 cells of the mouse are dealt with in detail to study the binding of SAA protofibrils in various conditions. Specifically, interaction of serum amyloid A fibrils with a cell surface binding site/receptor might alter the local environment to cause cellular dysfunction and to be more favorable for amyloid formation and prevention with alphaB-Crystallin. This is important in relation to the activity of membrane proteins, because losing the activity of such systems will ultimately lead to malfunction or death of the cell. The interactions of Serum Amyloid A (SAA) and Serum Amyloid A protofibrils with hepta 1-6 cells of the mouse are dealt with in detail to study the binding of SAA protofibrils in various onditions. The induced fluorescence, induced circular dichroism, FACScan and MTT assay results have shown the SAA and SAA prototfibrils binding and cell toxicity with the hepta 1-6 cells with different concentrations of alphaB-Crystallin 0.15-15 nM. Specifically, cells were incubated with 1.25-6.25 M SAA-FITC and SAA protofibrils-FITC assayed. The 50% viable hepta 1-6 cells at 4–6 M with an LD50 of 3.5 M. The interaction of serum amyloid A fibrils with a cell surface binding site/receptor might alter the local environment to cause cellular dysfunction and to be more favorable for amyloid formation. In the present study, concluding that the SAA fibrils and SAA protein binding and cell cytotoxicity was reduced in the presence of alphaB-Crystallin.
Temperature Dependence of Density and Dynamic Surface Tension of Groundnut Oi...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The Correlation of Parcel shape and Dimensions with Regulation in Creating Co...theijes
Commercial corridor in areas surround Jakarta has been rapidly growth. Some of this commercial corridor grows without any proper planning. Commercial corridor is created from available infrastructure that was used to connect some developed area. The rapid growth of commercial corridor shows irregularity and heterogeneity. The difference shape and dimension of parcel get similar treatment of building code. The characteristic of this commercial corridor created from the relationship of parcel shape and dimensions with building code as the controller. Relationship of parcel shape and dimensions with regulation can be analyzed easier using parametric simulation tools. The result of parametric simulation tools shows the characteristic of corridor as correlation between all variable. This paper uses one representative segment of corridor commercial in Serpong Tangerang.
First mitotic division: criterion for selection of potential IVF embryo – A S...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Evaluation of Heterogeneous Aquifers in Crystalline Rocks from Resistivity So...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
This document describes a Zigbee-based weather monitoring system that uses wireless sensors to remotely monitor various weather parameters without human intervention. The system collects data from sensors that measure temperature, humidity, wind speed and direction, rainfall, and other factors. An ARM7 microcontroller is used to multiplex sensor data and transmit it wirelessly via Zigbee modules. The received data is sent to a computer system. The system provides accurate, real-time monitoring over a large area at low cost compared to traditional weather monitoring methods. It was found to reliably transmit weather data from multiple remote locations.
Trusted Hardware Database With Privacy And Data Confidentialitytheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Discovery of Perched Aquifer When Assessing Aquifer Potential along the flood...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Study, testing & analysis of composit material based on munja fibretheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Impact on Aquatic Environment for Water Pollution in the Vahirab Rivertheijes
Water is a valued natural resource for the existence of all living organisms. Vahirab river is the prominent & important rivers for vital source of water from Jessore to Khulna. The prime reason of deterioration and pollution of the river water quality by effluents discharged from industries, municipal sewage, household wastes, clinical wastes and oils. The purpose of this study is to investigate the impact of this wastewater on the river and thus to provide an updated report on the state of water quality of river Vahirab. The water sample were collected from different areas in the river Vahirab and analyzed for physico-chemical parameters and fresh water elements in the month of July, 2013 to November, 2013. The values of temperature, turbidity, pH, chloride, hardness, DO, BOD, COD, Fe, As, Pb, Cd and Cr in the river water were measured. During study period the temperature, turbidity, pH, hardness, chloride, DO, BOD and COD were found to be 280C to 31.50C, 37 to 947 NTU, 7.2 to 8.01, 92 to 140 ppm, 9 to 34 ppm, 122 to 5.51 mg/L, 0.22 to 5.79 mg/L and 3.80 to 10.80 mg/L respectively. The concentration of Fe, Pb, As, Cd and Cr were found to be 0.10 to 2.60 ppm, 0.004 to 0.025 ppm, 0.001 to 0.004 ppm, 0.00015 to 0.0094 ppm and 0.001 to 0.006 ppm respectively. From the results of investigation, it was observed that the values of pH, Cl- , hardness, As, Pb, Cd and Cr were within standard limit but the values of temperature, turbidity, DO, BOD, COD and Fe were not within acceptable limit as recommended by WHO and BDS guidelines. The results obtained from this investigation will help the people of the research area to be conscious for using the water in the Vahirab river.
Effects of Variable Viscosity and Thermal Conductivity on MHD free Convection...theijes
This document summarizes a study that numerically investigates the effects of variable viscosity and thermal conductivity on magnetohydrodynamic (MHD) free convection and mass transfer flow over an inclined vertical surface in a porous medium with heat generation. The governing equations are reduced to ordinary differential equations using similarity transformations and then solved numerically using a shooting method. The results show that increasing the viscosity variation parameter, thermal conductivity parameter, magnetic parameter, permeability parameter, or Schmidt number decreases the fluid velocity, while increasing the heat generation parameter, local Grashof number, or mass Grashof number increases the fluid velocity. Skin friction, Nusselt number, and Sherwood number are also computed and presented in tabular form.
Inclusive On-line Learning Environments. New Approaches and Possible Applicab...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Optimum Operation of Direct Coupled Photovoltaic-Water Pumping Systemstheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Study on the Effect of Ggbs & M Sand in Self Compacting oncretetheijes
Conventional concrete is the most widely used construction material throughout the world because of its versality, mouldability, durability, and resistance to fire and energy efficiency. However, its major disadvantages like poor tensile strength, limited ductility and little resistance to cracking resists its use as a structural material. Hence, in order to overcome these difficulties several new materials have been developed in the recent past.Admixtures are ingredients other than water, aggregates, hydraulic cement and fibers that are added to the concrete batch immediately before or during mixing. Mineral admixtures are usually added to concrete in larger amounts to enhance the workability of fresh concrete, to improve resistance of concrete to thermal cracking, alkali-aggregate expansion and sulphate attack and to enable a reduction in cement content. The objective of this study is to evaluate the effectiveness of various mineral admixtures in producing SCC. In this study the scope of GGBS ( Ground granular blast furnace slag ) as a mineral admixture to some percentage replace cement in SCC were studied. The study showed that a maximum of 50% GGBS were able to be used as a mineral admixture without affecting the self-compactability
Design and Implementation of monitoring LAN user wirelessly by Android mobile...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Application of Coconut Coir and Fly ash in Sub grade strengtheningtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Theoretical work submitted to the Journal should be original in its motivation or modeling structure. Empirical analysis should be based on a theoretical framework and should be capable of replication. It is expected that all materials required for replication (including computer programs and data sets) should be available upon request to the authors.
The International Journal of Engineering & Science would take much care in making your article published without much delay with your kind cooperation
Natural Image Based Visual Secret Sharing Schemetheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Comparative Study Of Mppt Algorithms For Photovoltaic...Stacey Cruz
This document provides a comparative analysis of different single diode models for photovoltaic power sources. It aims to explore how increasing the complexity of the single diode model affects the simulated behavior of a PV module compared to experimental manufacturer data under varying conditions. The analysis calculates errors between each model and experimental data at different points to determine the best single diode model for different applications and conditions. The comparison concludes by identifying the most suitable models at low, medium, and high temperatures and irradiances as well as standard test conditions.
This document describes the fabrication and testing of a high-performance tandem organic solar cell with novel active layers. It utilizes a record-efficiency polymer, PBTI3T, in combination with other polymers like PTB7 and PSBTBT-Si to further enhance efficiency. Absorption spectra of the polymers show offset peaks that minimize spectral overlap when combined in a tandem device. Tandem devices were fabricated with PBTI3T and either PTB7 or PSBTBT-Si as the active layers. Results showed one of the highest open-circuit voltages reported and an overall power conversion efficiency above 6%, demonstrating the potential of tandem organic photovoltaics using high-efficiency polymers.
Seminar report on Flexible Photovoltaic TechnologyKumudGarg3
This report is relate to topic of Flexible Solar Cell. In this report you get content is introduction, introduction to flexible solar cell, types of solar cell, types of flexible solar cell, application n etc.
The document summarizes the state of photovoltaic technology, with a focus on silicon solar cells. It discusses:
1) Crystalline silicon solar cells currently dominate the market, achieving efficiencies up to 23.4% with PERC technology. Further improvements could reach 24.5% but new cell designs may be needed.
2) Challenges for PERC cells include maintaining performance gains with larger cell sizes. Heterojunction solar cells have reached 25.8% efficiency but challenges include high production costs.
3) Emerging technologies like TOPCon cells and IBC cells show promise but need to reduce costs to compete with standard PERC production. The future likely involves increased cell sizes
Photovoltaic ( Pv ) Based Distributed Generators EssayLaura Torres
The document discusses photovoltaic (PV) based distributed generators (DGs) that are controlled as current sources to deliver active power to the grid from a PV source. The proposed algorithm considers the environmental conditions' effect on active power generation and assigns reactive power references to the inverters after computing available inverter capacity. This ensures equal utilization of inverters irrespective of DG active power variations and avoids overloading inverters. Simulation results using MATLAB/Simulink confirm the algorithm's effectiveness over other methods.
A Framework For Epbt Calculation Of Roof Mounted...Lindsey Jones
This document discusses photovoltaic (PV) materials used in solar cells. It begins by noting that solar energy is one of the most widely used energy sources and that humans have developed technologies to capture solar energy for applications like cooking, heating, and powering devices. PV cells are then introduced as devices that convert solar energy into electrical energy. The essay aims to discuss PV materials and drive down production costs to make solar energy more affordable and widespread. Lowering costs is important as solar energy is a renewable source that could become a primary source of electricity.
Design a Highly Efficient Push-Pull converter for Photovoltaic ApplicationsEklavya Sharma
Design a schematic to extract maximum obtainable solar power from a PV module and use the energy for a DC application. This project investigates in detail the concept of Maximum Power Point Tracking (MPPT) which significantly increases the efficiency of the solar photovoltaic system.
Sustainability of the Installed Battery-less PV Panel Systems at Two Governme...IJAEMSJORNAL
This document summarizes a study that assessed the sustainability of battery-less photovoltaic (PV) panel systems installed at two government institutions in Pampanga, Philippines. The study found that the PV systems decreased the energy costs of both institutions compared to before installation. Specifically, Institution A saw an average 0.72% decrease in energy usage and 0.43% decrease in costs, while Institution B saw higher decreases of 12.88% and 13.59% respectively. The study also determined that the PV panels at Institution A had an efficiency of 27.98% while those at Institution B had 52.47% efficiency. A manual was created based on the study to provide guidance on operating and maintaining the PV systems.
Ant Colony Optimization for Optimal Photovoltaic Array Reconfiguration under ...IRJET Journal
This document presents an optimization approach for optimal reconfiguration of a photovoltaic (PV) array under partial shading conditions. The approach uses Ant Colony Optimization (ACO) to determine the optimal electrical connections between PV modules in a total cross-tied array layout. The objectives are to maximize power output and minimize switching operations. The ACO algorithm considers factors like irradiance levels and switching costs to find a configuration that distributes shade uniformly and extracts more power than a static layout. Simulation results show the ACO approach enhances power output compared to the initial cross-tied configuration.
Design and Modeling of Grid Connected Hybrid Renewable Energy Power GenerationIJERA Editor
This paper proposes a design and modeling of grid connected hybrid renewable energy power generation. The
energy system having a photo voltaic (PV) panel, Srg wind turbine and fuel cell (sofc) for continuous power
flow management. Fuel cells (storage & generating) are added to ensure uninterrupted power supply due to the
discontinuous nature of solar and wind resources. Renewable energy generated during times of plenty can be
stored for use during periods when sufficient electricity is not available. But storing this energy is a difficult
task: batteries and similar technologies perform well over short timescales, but over periods of weeks or months
a different approach is necessary. Energy storage in the form of hydrogen is one such possibility: excess
electricity is fed into an electrolyser to split water into its constituent parts, oxygen and hydrogen. The hydrogen
is then used in fuel cells to produce electricity when needed which will overcome the problem of storage. This
work is mainly concentrated on the design, analysis and modelling of Fuel cells and Analysis and modelling of
Switched Reluctance Generator (SRG) in the application of Wind Energy Generation and pv cell. Also an
effective approach is proposed in this thesis to ensure renewable energy diversity and effective utilization. The
pv cell, wind and fuel cell renewable energy system is digitally simulated using the MATLAB/SIMULINK
software environment and fully validated for efficient energy utilizations and enhanced interface power quality
under different operating conditions and load excursions
IRJET- Modeling, Simulation and Control of a Photovoltaic Energy System w...IRJET Journal
The document presents a photovoltaic (PV) energy system with a fuel cell backup to ensure continuous operation of connected loads. The PV array normally powers the loads when solar irradiance is within its nominal range. When irradiance falls below a threshold, the fuel cell takes over to feed the loads. The proposed hybrid system is simulated in MATLAB/Simulink. Results show the system can efficiently address the intermittent nature of PV power by integrating a fuel cell backup.
A Systematic Review of Renewable Energy Trend.pdfssuser793b4e
This paper systematically and successfully reviewed the renewable energy trend from 2010 to 2023. This review
detailed the difference renewable energy and conclusion was drawn that solar photovoltaic (PV) energy has the
leading trend in power generation growth and innovation. This research work explained in detail the most recent
solar photovoltaic optimization techniques and it was observed from the review that hybridization of intelligent and
non-intelligent maximum power point tracking technique has the best tracking power conversion efficiency. The
advantages and disadvantage of solar PV together with the solar optimization and innovational growth trends were
examined. This research showed that clean and renewable energy sources will continue to grow and the solar energy
industry is expected to experience significant growth and rapid innovation in the next 10 years. From the observed
rapid growth and innovation trend in solar energy, the world will have a very cheap, abundant and clean energy
before 2050.
IRJET- Grid Connected Solid Oxide Fuel Cell and Solar Photovoltic Hybrid Powe...IRJET Journal
This document describes a proposed hybrid power generation system combining a solid oxide fuel cell (SOFC) and solar photovoltaic (PV) system. It begins with background on the individual systems - SOFCs produce electricity through chemical reactions while PVs use solar cells to convert sunlight to electricity. The document then proposes a control system to manage the hybrid system using both series and shunt active power compensation to correct voltage and current nonlinearities from loads. Simulation results are presented showing the hybrid system can improve power quality by correcting harmonics and maintaining unity power factor.
“SIMULATION ON OPTIMISATION OF POWER QUALITY USING HYBRID POWER SYSTEM”IRJET Journal
This document presents a simulation study on optimizing power quality in a hybrid power system comprising hydro and solar photovoltaic energy sources. The study was conducted by students from the Department of Electrical Engineering at RIT Karnataka, India. The simulation aimed to ensure reliable power supply by combining renewable energy sources and address power quality issues like voltage sags caused by faults. MATLAB/Simulink was used to model a hybrid system with a hydro turbine and solar PV array supplying power to a three-phase load. Maximum power point tracking controllers were used to optimize output from each source. A dynamic voltage restorer scheme was also tested to compensate for voltage sags and improve power quality. The results demonstrated effective power generation from the hybrid system
Report on the IMPROVING THE EFFICIENCY OF SOLAR PHOTOVOLTAIC POWER GENERATION...Yuvraj Singh
The document is a seminar report on improving the efficiency of solar photovoltaic power generation. It discusses several ways to improve efficiency, including improving the conversion efficiency of solar panels, using automatic solar tracking systems, implementing maximum power point tracking technology, and exploring complex photosynthesis mechanisms. The report analyzes these methods and concludes that using these technologies can effectively improve the efficiency of solar power generation.
Even though PV systems have been promoted as a green form of electrification, such systems are still contributing to environmental impacts after considering life-cycle impact during material extraction, manufacturing processes of its components, installation, operation, and maintenance. This paper presents a life-cycle assessment to quantify the environmental impact of residential-scale grid-connected PV systems in Malaysia using monocrystalline silicon PV module. LCA had been carried out by using OpenLCA 1.8 software, Ecoinvent 3.5 database, and impact assessment method of IMPACT2002+ and CED. The influence of varying system capacity from 3 to 12 kWp, system lifetime of 21, 25 and 30 years, and solar irradiation of 1560.8, 1651.8, & 1935.5 kWh/m2/yr, were investigated. The results revealed that the greenhouse gas emissions rate, cumulative energy demand, and energy payback time of residential-scale grid-connected PV systems in Malaysia ranged from 37.97 to 67.26 g CO2-eq/kWh, 4387.10 to 4699.99 MJ/m2, and 6.37 to 7.90 years, respectively. This study also evaluated indicators of energy return on investment. The overall finding implies that the installation of residential-scale grid-connected PV systems in Malaysia offers significant potential for GHG emissions reduction in the country.
This document summarizes a presentation on using carbon nanotubes in solar panel technology. It discusses how carbon nanotubes can improve the efficiency of solar cells compared to traditional organic solar cells. Carbon nanotubes are classified as single-walled or multi-walled nanotubes. Carbon nanotubes and a polymer called MEH-PPV-CN are used as materials in constructing a carbon solar cell. The cell works by generating electrons when exposed to light, which are transferred between energy bands and build up voltage. Adding carbon nanotubes can increase the cell's efficiency by improving light absorption and electron transport. Potential applications include using carbon nanotubes in the photoactive layer or as transparent electrodes.
This document analyzes the technical and economic feasibility of using off-grid solar photovoltaic technology to generate electricity in Peshawar, Pakistan. It finds that while solar PV electricity is currently more expensive than grid electricity, subsidies from the Khyber Pakhtunkhwa government could help promote solar adoption. The document estimates solar energy production potential in Peshawar and calculates the electricity costs and payback periods for a 10kW residential solar system under different capital cost scenarios. It also analyzes the system's net present value, internal rate of return, investment payback period, and energy payback time. The document concludes that while upfront costs are high, solar PV could ensure cleaner energy and reduce greenhouse
IRJET- Microbial Fuel Cell for Chemical Zone Waste Water AmbernathIRJET Journal
This document summarizes a study on using microbial fuel cells to generate electricity from wastewater. The study constructed microbial fuel cells with two chambers connected by a salt bridge, with a graphite anode in one chamber filled with wastewater and an aluminum cathode in the other filled with electrolyte. Testing of the fuel cells over 9 days using wastewater from two locations found maximum voltages of 1909mV and 1944mV. The document also reviews previous literature on microbial fuel cells and discusses factors that affect power generation as well as the materials, reactions, and methodology used in the study.
Modelling & Simulation of PV Module Connected with Three-Port DC ConverterDr. Amarjeet Singh
Of the world’s electricity is being generated through conventional sources of energy like coal and atomic energy. People have realized the dire effect of using these fuels, and the amount of CO2 being released into the environment. There has been a shift in emphasis towards cleaner ways of generating electricity in recent years. Solar energy is abundantly available and the cleanest renewable energy source available in the world and is ready to use for a variety of applications, such as the generation of electricity for residential, commercial, or industrial consumption and have become very competitive solutions. It can be seen that there is trend of solar photovoltaics (PV), which has seen rapid growth over the years. The increasing trend of adopting PV system allows consumers to be known as producers or “Prosumers”.
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Recent Developments in Organic Polymers Based- Photovoltaic Cells
1. The International Journal Of Engineering And Science (IJES)
|| Volume || 4 || Issue || 5 || Pages || PP.01-14 || 2015 ||
ISSN (e): 2319 – 1813 ISSN (p): 2319 – 1805
www.theijes.com The IJES Page 1
Recent Developments in Organic Polymers Based- Photovoltaic
Cells
Zinzuwadia Mithil, Kothari A Rishabh , Gupta Hansika, Korde Madhulika.,
Prerna Goswami , M.A.Kerawalla
Institute of Chemical Technology (ICT), Nathala Parekh Marg, Matunga, Mumbai-400 019, India,
ABSTRACT: In this review article, the uses of organic polymers to make photovoltaic cells have been
discussed. The focus is mainly on discussing organic polymer based photovoltaic (OPVs) solar cells, the
development of new device technologies and donor polymers that are being researched on. The recent
development in this field has led to improved OPV performances with power conversion efficiencies as
phenomenal as 9%. However for commercial application of this kind of OPVs, an improved device structure
and cost effective processing methods are required. This article reports the polymer design criteria, energy level
matching, nano-morphing of polymer/acceptor blend films and local dipole moments of the polymer chains that
have been developed in the research that took place over the past 4 years. We emphasize the importance of
developing new methods for designing polymers with improved physical properties and development of new
technologies to fully understand the fundamentals of OPV mechanisms, which will help improve the power
conversion efficiency of the OPV.
KEYWORDS - Power Conversion Efficiency, Bulk-heterojuntion, Hybrid Solar Cells, Benzo[1,2-b:4,5-b′]
Dithiophene, Fused Dithienogermolodithiophene, Selenium-substituted
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Date of Submission: 11-April-2015 Date of Accepted: 05-May-2015
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I. INTRODUCTION
Solar energy proved as a clean, sustainable alternative source to fossil fuels can meet the continuously
growing global demands of energy.[1] Solar cells based on the photovoltaic effect are an effective method to
convert solar energy into electricity. Today, standard solar panels based on multi-layer single crystalline silicon
have achieved power conversion efficiencies of more than 40% which has increased their usage [2] but on the
other side, the relatively high cost of the crystalline silicon-based solar panels has led to their depletion of
widespread and large scale usage. Therefore, the need of the hour was to find another solar cell technology
which can exhibit lower manufacturing costs by utilizing inexpensive and abundant materials. Due to this,
polymer solar cells (PSCs) based on organic semiconducting donor and acceptor materials are being pursued by
the scientific and industrial communities. Some advantages conveyed by PSCs are that they are relatively
cheaper, have tuneable flexibility, have high specific weight, are semi-transparent, get easily integrated into
other objects, low environmental impact and allow for scalable material production using various organic
synthetic methods and cost-effective roll-to-roll coating and printing techniques.[3-5].
As a good donor material in the PSCs, the conjugated polymer should possess atleast the following three
intrinsic features:
i. A broad and strong absorption band providing efficient harvest of solar light available at any given time;
ii. Appropriate highest occupied molecular orbital (HOMO) level and a lowest unoccupied molecular orbital
(LUMO) level for establishing efficient charge separation with low energy loss;
iii. High hole mobility which facilitates good charge transport.[6]
In addition to these requirements, they must also be extremely soluble in organic solvents, and when they are
blended with (6,6)-phenyl-C61(or C71)- butyric acid methyl ester (PC61BM or PC71BM), bi-continuous
networks with nanoscale phase separation should be formed.[7-9] . In order to meet all these specific
requirements, structural components in conjugated polymers, including their backbones and side groups, must
be designed and modified with utmost care. Continuous research and innovations can reduce the cost of
electricity produced by PV (photovoltaic) significantly. The levelized cost of PV electricity was approximately
0.6 €/kWh in Germany in the year 2007 while PV electricity reached the private household price level of
approximately 0.25 €/kWh by the end of 2011. Thus solar electricity is gradually reaching the grid parity for
private household electricity. Major reduction of costs of PV-modules and inverters have led to this positive
development. But according to the EIA Annual Energy Outlook 2011 hydro-, coal- or gas-powered plants can
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produce electricity well below 0.1 €/kWh. This means that, for making a significant contribution to the global
electricity or energy production, the costs for solar electricity still needs to undergo substantial further cost
reductions.
Thus cheaper PV-electricity can be achieved in two ways :-
(i)By increasing the power conversion efficiency maintaining PV-material costs the same (wafer-based solar
cells (1st generation) or high efficiency concepts (3rd generation)).
(ii)Or by developing low-cost, moderate efficiency PV-material (thin-film PV, organic photovoltaic).
Thus three main contributors can be identified on analysing the typical cost structure of a grid connected PV-
system:
(i)PV module,
(ii)Installation/balance of system and
(iii)Power electronics (inverter).
Thus for PSCs to fully develop from research and development to cost effective products, continuous
improvement in solar cell efficiency needs to be carried on. A PCE (Power conversion efficiency) of 10% or
more in devices with sizable area is regarded as an important threshold for practical and widespread usages of
polymer solar cells. It has been found out that PSCs showing 15% PCE with a 20-year lifetime can provide
electricity at a cost of around seven cents per kilowatt-hour which makes solar energy competitive with
conventional sources of electricity.[10-11] And thus for achieving this PCE goal, major advances in new
materials and device technology is highly essential. [12-13]
II. BULK HETEROJUNCTION (BHJ) SOLAR CELLS
The most popular class of PSCs , the bulk heterojunction (BHJ) solar cells are based on composite
materials composed of low band-gap conjugated polymers as the electron donor, and substituted fullerenes as
electron acceptor materials. Due to successive developments in material design and synthesis, control in the
morphology of the bulk heterojunction (BHJ) composite and device optimization, power conversion efficiencies
(PCEs) of more than 8% have been achieved.[14-23] Efficiency approaching 10% has been disclosed in small
area solar cells, which indicates the rapid progress over the last 5 years and the great potential of these polymer
solar cells as an alternative source of energy.[24]
Detailed balance limit and charge transfer complex
Veldman et al. [25] conducted a number of experiments on the charge transfer complex in bulk heterojunction
and found out that the minimum open circuit loss amounts to 0.6 eV unlike the lower band gap of the acceptor
and the donor. The open circuit voltage( Voc ) and the HOMO–LUMO difference of the donor acceptor pair as
well as the Voc and the energetic position of the charge transfer complex emission showed a linear relation. Now
they used this relation and assumed values for the External Quantum efficiencies (EQE) and the fill factors (FF)
to calculate the ultimate efficiency of BHJ cells. With a FF and EQE of about 65% they found a maximum
efficiency of 11% which was obtained at a band gap around 1.4 eV. This highlights the importance of the charge
transfer complex formed in organic solar cells.[26]
Fig 1.Illustration of the different losses in an perfect solar cell, photon energy larger or smaller the absorber gap
(left); power conversion efficiency losses according to the Shockley–Queisser analysis. _E1is the photon access
energy which is lost due to fast relaxation of the photoexcited charge carrier. Photons with energy E2smaller
than the band gap are not absorbed by the semiconductor.
In 2009 Kirchartz et al.[27] calculated the radiative efficiency limit of organic solar cells. Adapting the
Shockely–Queisser approach(above figure) they estimated a maximum efficiency >20% for pristine polymer
and polymer fullerene absorbers. The analysis showed a power conversion efficiency of max. 4.2%, which was
investigated upon and the following losses were revealed:
1. Optical losses.
2. Exciton losses due to insufficient transport of excitons to the next donor– acceptor interface or due to
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inefficient exciton dissociation.
3. Non-radiative recombination losses.
4. Charge carrier collection losses due to insufficient mobilities.
To overcome the non-radioactive recombination losses, the morphology of the BHJ films was required to be
appropriate [28] so that excitons can be created within a diffusion length of a donor-acceptor interface, leading
to greatly enhanced quantum efficiency of charge separation.
Yu and co-workers [15,29,30] reported a series of examples of donor 95 copolymers incorporating TT and
benzo (1,2-b;4,5-b’) dithiophene (BDT) (PTBs). The planarity of the BDT molecule with an extended π
conjugated system conveys rigidity to the polymer backbone, enabling the polymer to form an assembly with
better π−π stacking and high hole mobility. This improves the hole mobility and hence reduces the losses.
Recently Koster et al.[31]and Gruber et al.[32] pointed out that either a very weakly absorbing or a strongly
absorbing charge transfer state leads to the highest power conversion efficiencies under the radiative efficiency
limit. A weakly absorbing CT minimizes the losses in open circuit voltage while a strongly absorbing charge
transfer state allows the collection of additional photons(solar). In both cases, the maximum efficiency in the
radiative limit is
above 30%. The situation is illustrated
in below fig. Here we assume a charge
transfer state with different absorptions strength with a constant spectral width of 0.2 eV. They performed the
calculations using a black body radiator with a surface temperature of 5800 K as source of light and intensity at
the solar cell surface of 1000 W/m2
and a solar cell temperature of 300 K.
Fig 2.(a) Profile of an ideal absorber with a weak and broad charge(0.2 eV) transfer absorption feature. (b) PCE
of a solar cell with a absorption profile (a) and different absorptions strength (CT) of the charge transfer state
Giebink et al.[33] found a “Thermodynamic Efficiency Limit of Exciton Solar Cells” of
22–27%—demonstrating again the performance potential of organic solar cells under idealized conditions
without any losses. Similarly high efficiencies for bulk heterojunction solar cells can be found out by applying
pure thermodynamic considerations.
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III. ORGANIC—INORGANIC HYBRID SOLAR CELLS
Organic—inorganic hybrid solar cells combine inorganic nano particles and organic (normally
conjugated polymers), with the intent of using the advantages associated with both material groups [34,35]. The
device fabrication and operation of hybrid solar cells is very similar to that of organic solar cells, the only
difference being that the organic electron accepting material of PCBM (or other fullerene derivatives) is
replaced by an inorganic nanoparticle. The inorganic electron acceptor material provides many advantages to
the system, whilst maintaining low cost process ability.
First of all inorganic materials are more environmentally stable than organic materials [36]. Adding
these materials to OPV devices assists in overcoming one of the major downfalls of this technology, ie the photo
induced degradation of the conjugated organic semiconductors. Second, photogeneration of charge carriers is
achieved by excitons absorbed in the inorganic material [37,38]. Also the contribution of light absorption by an
inorganic acceptor is potentially greater than the absorption contribution of PCBM in PSC devices [39,40].
Finally, inorganic quantum dots are also known for ultrafast photoinduced charge carrier transfer to organic
semiconductors. This transfer rate has been observed and calculated in the order of picoseconds [41]. As this
transfer rate is faster than the competing recombination mechanisms ,efficient charge transfer is established
between the donor and acceptor .
Device operation
The exciton created on the absorption of a photon is dissociated at the donor-acceptor interface. When they
separate, the electron is transfered to the acceptor material at an interface and travels to the cathode for charge
collection. The hole produced in the donor material is collected at the anode after travelling throughout the
polymer. This process is displayed as (a) in Fig. When light is absorbed in the acceptor material, an exciton is
formed which must be dissociated by the offset in energy of the donor HOMO level and the acceptor valence
band edge. The hole is transferred to the donor at an interface and reaches the anode whilst the electron remains
in the acceptor material and travels to the cathode for collection. This process is displayed as (b) in above Fig.
Various design considerations are crucial while choosing an appropriate inorganic material. It has been
identified that an optimal electronic design for such a material would be a bandgap of 1.5eV and a HOMO level
offset of 0.3eV so that it allows both a significant absorption contribution as well as a large open circuit voltage
(Voc). There exist additional physical considerations which must also be taken into account. The different
materials which have so far been considered have both advantages and disadvantages; however, none of
materials has been coupled with a polymer to provide an electrical performance superior to that of an OPV
device, for which PCEs of 10% have been achieved. The major limitation to device performance is due to the
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effect of the insulating surface ligand on the electrical performance of the nanoparticles. Recent research aim at
realizing the entire potential of this technology by reducing the negative effects.[42] Silicon is a good choice for
nanohybrid solar cells and it has higher dielectric constant as compared to PCBM. It has strong electronic
properties which is desirable for us. Lie et al studies this and found the bandgap of Si N Cs, to be 1.5eV.Due to
the relatively small bandgap, they provided an enhanced absorption profile. The absorption profile of
P3HT:PCBM is compared with that of Si NCs in figure
Fig 4. Optical absorption spectra forP3HT, silicon nanocrystals and P3HT:Si NC blendfilm [88], (b) J–V
characteristic curves of P3HT:SiNCsolar cells under 100 mW/cm2, AM1.5G conditions. This shows a
comparison of an as-cast and annealed device. The annealing conditions were 150 C for 120min ,Schematic
diagram of the procedure used to form hybrid solar cells incorporating silicon nanowires. First, the nanowires
were pressed into the P3HT:PCBM blend, then the wafer was removed by the application of lateral force
Scharber et al in 2006 studied the relationship between the open circuit voltage and the energy levels of the D-A
blend for 26 different BHJ devices. Keeping the acceptor(PCBM) constant, the donor material was
varied.[43,44] The analysis suggested linear relationship between the open circuit voltage and the diagonal
bandgap of the heterojunction but there also existed a loss factor in the BHJ design.
However there are problems related to the increased density of trapped states and limited control over the D-A
nanomorphology which seemed to have hindered progress in this field. However, a post production annealing
process could improve the nanomorphology and hence improve the PCE. Thermal treatments cause crystallinity
in the polymer hence allowing better hole mobility [45-47].Similarly, many ways of nanostructuring are
possible which improve the electron mobility in the polymer(below Fig.).Inorganic materials like semiconductor
ZnO have come to the limelight due to their vertically aligned structures and high electron nobilities. Hence,
many new materials were explored to work towards optimizing such parameters.
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Fig5. Schematic representation of the possible nanostructured architectures for inorganic acceptor materials.
Depicted are (a) quantum dots, (b) nano rods, (c) branched nano rods and (d) porous single crystal.
IV. FROM ALKOXY-SUBSTITUTED BENZO[1,2-B:4,5-B′]DITHIOPHENE UNITS
(BDT) TO
2-Alkylthienyl-Substituted BDT
BDT based polymers are one of the major families of polymer based photovoltaic cells.[48-60] After studying
the reported works on these PVCs, it has been found that efficient photovoltaic materials can be obtained by
copolymerizing BDT units with other types of conjugated building blocks.[48] Thus, 8−9% PCEs have been
obtained from BDT and Thieno(3,4-b) Thiophene (TT) Copolymers, [53-58] the BDT andTPD copolymers,[59]
the BDT and diketopyrrolopyrrole (DPP) copolymers,[60,61] and so on. Therefore, how to improve
photovoltaic properties of the BDT-based polymers is a very important topic for molecular engineering and thus
further research needs to be carried on.
4.1 Design strategies of the 2D-conjugate BDT based polymers
In the above figure, there are two groups in which six BDT-based polymers are put in. In Group 1, the
BDT units in the polymers are substituted by alkoxyl groups; in Group 2, the backbone structures of the three
polymers are identical and possess alkyl side groups as the analogues of Group 1, but the
Fig 6.evolution of moleculer structures based structures for three BDT based polymers from alkoxyl substitution
to 2-alkylthienyl substitution
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Alkoxyl groups linked with the BDT units are replaced by 2-alkylthienyl groups, so that the surface area of
conjugation of their backbones can be expanded toward the vertical direction. The comparisons between the
polymers in these two groups will provide further important information on the effects of the 2D-conjugated
structure.[62,64] According to the data collected in Table 1, it can be concluded that due to the replacement of
the alkoxyl groups with the 2-alkylthienyl groups, the absorption bands of the polymers get red-shifted slightly,
while their HOMO levels are little altered. Also, the thermal decomposition temperatures (Td) of the polymers
in Group 2 are improved by quite an extent. In addition to that, the polymers in Group 2 showed higher hole
mobility and improved PCEs in PSCs compared to the polymers in Group 1.
4.2. Molecular Energy Level Modulation of the 2D-Conjugated BDT-Based Polymers
Recent studies in the molecular designs of 2D-conjugated BDT-based polymers showed that molecular
energy levels of this type of polymers can be tuned effectively by altering the conjugated side groups.
Figure - Evolution of molecular structures for BDT-based polymers with different conjugated side groups.
Right from alkoxyl substitution to 2-alkylthienyl substitution, little change in their HOMO levels are observed,
meaning both the 2-alkylthienyl groups and the alkoxyl groups have similar influence on molecular energy
levels of the BDT-based polymers. Yang et al. synthesized two
Fig 7.Evolution of molecular structures for BDT-based polymers with different conjugated side groups.
copolymers namely BDT and DPP [61] in which thienyls and phenyls were respectively used as the conjugated
side groups.
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To enable clear comparisons, the analogous polymers based on alkoxyl-substituted BDT36 are shown in above
Figure , and each of their photovoltaic properties is collected in Table 2. The figure shows the TEM images of
the corresponding polymer:PC71BM blends significantly and the molecular structures of three polymers based
on the BDT and DPP units. The substituent’s on BDT were changed from alkoxyl to 2-alkylthienyl and then to
para-alkylphenyl, their HOMO levels decreased gradually, from −5.16 to −5.30 eV and then to−5.35 eV; while
the Voc’s of the corresponding PSCs got increased from 0.68 to 0.73 V and then to 0.76 V. Thus molecular
energy level of the 2D-conjugated BDT-based polymers is also affected by altering the substitution positions of
the alkyls.[65] Recently, Huang et al. did a detailed study on the effect of alkyl substitution position on
molecular energy levels of the 2Dconjugated BDT-based polymers and noticed a PCE of 7.1% with a high Voc
of 0.9 V.[66] The molecular energy levels can also be tuned by introducing functional groups onto their
conjugated side groups. In a previous work, when meta-alkoxyl-phenyl was used as side groups instead of para-
alkoxyl-phenyl in a conjugated polymer, deeper HOMO level and thus improved Voc was noticed.
Fig 8. Molecular structures of three polymers based on BDT and DPP units, and TEM images of the
corresponding polymer:PC71BM blends.
Based on the discussion in this section it should be concluded that molecular energy levels of the 2D-conjugated
BDT-based polymers can be effectively tuned according to the requirements.
4.3. Backbone Conformation Modulation of the2D-Conjugated BDT-Based Polymers
Getting bicontinuous nanoscale phase separation in the blends of polymer and PC71BM (an electron acceptor) is
one of the key issues to ensure efficient PCE. Sometimes, the formation of large size aggregations of polymer
and PC71BM in the blends is one of the most important obstacles in order to realize high photovoltaic
performance.As shown in Figure , the PBDPPO:PC71BM blend showed large aggregations (>100 nm), so that
the excitons generated in the polymer and PC71BM domains cannot diffuse to the D/A interface efficiently due
to the limited exciton diffusion length and also the D/A interface in the blend is not big enough to perform
efficient charge separation. Although the replacement of the alkoxyls with the 2- alkylthienyls definitely have a
positive influence on improving compatibility between PCBM and the polymer based on DPP and BDT,[64]this
method doesn’t have much of an effect on tuning crystallinities of the BDT-based polymers.[67,70] From the
results discussed above it can finally be concluded that morphological properties of the 2D-conjugated BDT-
based polymers can be tuned by a variety of methods. The superior properties of 2D-conjugated BDT-based
polymers along with high PCEs make them potential candidates for highly efficient photovoltaic solar cell
devices with varied architectures. The molecular structure evolutions from BDT to 2D-conjugated BDT is an
excellent reference for the design and development of organic-polymer electronic materials. These excellent
results indicate that 2D-conjugated BDT is a very useful building block for the design of high performance
photovoltaic polymer solar cells.[71]
V. FUSED DITHIENOGERMOLODITHI- -OP HENCE LOW BAND GAP
POLYMERS
Another promising class of polymers for the photovoltaic applications are the so-called ladder
polymers, in which linked aromatic units such as thiophene or benzene are forced to be co-planar and fully
conjugated using the bridge heteroatoms.[72] The enforced co-planarity reduces rotational disorder which leads
to lowering of reorganization energy and potentially increasing charge carrier mobility.[73] The bridging atoms
also serve as a point of attachment for the necessary solubilizing groups needed to ensure processable materials.
Thus here we have dithienogermolodithiophene which is the polymer in which two thieno(3,2-b)thiophene units
are held co-planar by a bridging dialkyl germanium is polymerized with with N-octylthienopyrrolodione by
Stille polycondensation giving a polymer, pDTTG-TPD, which has an optical band gap of around 1.75 eV and
is combined with a high ionization potential. BHJ solar cells based upon pDTTG-TPD:PC71BM blends
afforded efficiencies up to 7.2% without the need for thermal annealing or processing additives.
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Fig 9. Synthesis process
The synthesis of the polymer pDTTG-TPD is shown in scheme 1. Dibromination of commercially available TT
with NBS, followed by protection of one of the aryl bromides as a trimethylsilyl group resulted from the
previously reported TT derivation 3. In this method we use the property of arylhalides to undergo base
catalyzed rearrangements (the halogen dance mechanism) to produce the most stable organometallic species.
The treatment of 5-bromothieno[3,2-b]thiophen-2-yl) (trimethyl) silane 3 with one equivalent of LDA at -78°C
Resulted in the rearranged 6-bromothieno[3,2-b]thiophen-2 yl) (trimethyl)silane. This was not isolated, but was
oxidatively dimerised in situ by treatment with CuCl2 to produce the dibromide 4 in 70%. This was dilithiated at
- 90°C and reacted with dibromobis (2-ethylhexyl) germane to afford the ring closed germole 5 in 60%. Note
that the di-anion of 4 had a tendency to decompose by ring opening due to the electron rich nature of the
thieno[3,2-b]thiophene. This degradation could be minimized by maintaining the temperature below - 90°C, and
using diethyl ether rather than THF as the solvent. The conversion to the required distannyl derivative of
germole 5 was achieved by treatment with NBS, followed by lithiation of the resulting dibromide and
stannylation at low temperature.[74] The optical properties of pDTTG-TPD were characterized by UV-vis
absorption spectroscopy. As shown in below Figure , the solution spectrum displays a maximum at 595 nm and
a shoulder at 643 nm. The shoulder is assigned to the aggregation of pDTTG-TPD since heating to 85 °C
results in a 7 nm blue shift of the maximum and a decline in the relative intensity of the shoulder. This suggests
the existence of inter-molecular stacking even in dilute solution. Upon film formation the absorption red shifts
and the relative peak intensities change, with the former shoulder now becoming the strongest intensity peak at
663 nm with a weaker shoulder at 608 nm. Such changes are indicative of an increasing degree of polymer
aggregation and backbone planarization com-pared to solution. From the onset absorption in the solid state, the
optical band gap was found to be approximately 1.75 eV.
Fig 10. Absorption of pDTTG-TPD in chlorobenzene and of pDTTG-TPD in 0.1 M Bu4NPF6 acetonitrile
solution.
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In order to calculate the band gap and energy level of pDTTG-TPD we measured the redox behavior by cyclic
voltammetry (CV) as a thin film. The inserted curve in Figure shows that pDTTG-TPD possesses a reversible
oxidation and an irreversible reduction. Based on the assumption that the absolute energy level of
ferrocene/ferrocenium (Fc / Fc+
) is -5.1 eV to vacuum [75], the energy levels of the highest occupied molecular
orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) were evaluated with the value of - 5.68 eV
according to their oxidation onset potentials and according to their reduction onset potentials the value was -3.88
eV. As a result the value of electrochemical band gap was calculated as 1.8 eV, which is in excellent agreement
with that of optical band gap.
The photovoltaic performance of pDTTG-TPD was investigated in bulk heterojunction devices with a
conventional device configuration of ITO/PEDOT:PSS/PTTGTPD:PC71BM/Ca/ Al. The best device
performance based on the film spin-coated from an optimal 1:2 (w/w) ratio of pDTTG-TPD/PC71BM blend
solution in dichlorobenzene at 80 °C can be seen in the above figure. Further annealing at 140 °C did not change
the performance. The optimum active layer thickness was found to be between 90-110 nm, limited by the
limited solubility of the donor polymer. The illuminated (A.M. 1.5) current density-voltage (J-V) curve in figure
2 exhibits a Voc of 0.81 V, a Jsc of 13.85 mA cm-2
and a FF 0f 64%, leading a PCE of 7.2%. Average device
efficiencies were 6.8% . This good performance was achieved without the use of any processing additives. Such
additives are often required in the case of largely amorphous donor polymers to drive phase segregation during
the film drying process by preferential solubility of one of the components in the additive.
VI. A SELENIUM-SUBSTITUTED LOW-BANDGAP POLYMER
The reduction of the band gap and the enhancement of the charge transport properties of a LBG (low
bandgap polymer) polymer (PBDTT-DPP) can be accomplished simultaneously by substituting the sulfur atoms
on the DPP (diketopyrrolopyrrole ) unit with selenium atoms. The newly designed polymer,benzo[1,2-b;3,4-
b]dithiophene-alt-2,5-bis(2-butyloctyl)-3,6-bis(selenophene-2-yl)pyrrolo[3,4-c]pyrrole-1,4-dione} (PBDTT-
SeDPP, Eg = 1.38 eV), shows excellent photovoltaic performance in single junction devices with photo-
response up to 900 nm and PCEs over 7%. Visibly-transparent solar cells and tandem polymer solar cells and
based on PBDTT-SeDPP are also demonstrated with a 9.5% and 4.5% PCE, which are more than 10%
enhancement over those based on PBDTT-DPP
The SeDPP monomer was synthesized by first adding the carbonitrile group onto the 2-position of selenophene.
The SeDPP core unit was formed by condensation reaction with selenophene-2-carbonnitrile and
diisopropylsuccinate in a basic environment. It should be noted that decreasing the reaction temperature (from
120 C to 80 C) and increasing the reaction time (from 2 hours to 12 hours) can enhance the yield of this step to a
great extent, probably due to the lack in stability of the selenothiophene-2-carbonnitrile at high temperature.
Then, 2-butyloctyl chains were attached onto the DPP core to ensure it was soluble and then finally the
bromination was performed by N-bromosuccinimide (NBS) under Argon protection. To fully measure the effect
of the Se-substitution on the DPP unit, the furan and thiophene counterparts (PBDTT-FDPP and PBDTT-DPP)
were also synthesized and characterized for comparison, and their chemical structures are shown in Figure a.
The polymers PBDT-FDPP, PBDTT-DPP, and PBDTT-SeDPP were obtained via Stille-coupling
polymerization, and the detailed synthetic route as well as structural characterization is described in the
Supporting Information. The gel permeation chromatography (GPC) measurements measures similar average
molecular weights (Mn) of 35.2 kDa, 40.7 kDa, and 38.4 kDa for PBDTT-FDPP, PBDTT-DPP, and PBDTT-
SeDPP, respectively. It is seen that higher Mn batches of PBDTT-DPP and PBDTT-SeDPP showed very poor
solubility and cannot be used for solution processing. And higher Mn batches of PBDTT-FDPP showed similar
or even lower performance. For the consistency of the report, polymers with similar Mn values are used here.
The polydispersity index of these three polymers was also determined by GPC to be around 2.1. These polymers
can be dissolved in chloroform (CF), chlorobenzene (CB), and dichlo-robenzene (DCB).
Figure b shows the comparison of the ultraviolet/visible (UV/Vis) absorption spectra of the polymer thin films.
All three polymers have a main absorption range starting from ∼550 nm, and the absorption edges are from 810
nm to 900 nm. The absorption shapes are similar to each other, which indicate the characteristics of the BDTT-
DPP backbone system. The new PBDTT-SeDPP polymer displays a clear red-shift of the absorption onset as
well as the maximum peak value (nearly 50 nm) as compared to PBDTT-DPP. According to the onset of the
film absorption spectra, the optical band gap of PBDTT-DPP, PBDT-FDPP and PBDTT-SeDPP are calculated
to be 1.46, 1.51 and 1.38 eV, respectively. The relatively low absorptivity in the visible region (400–650 nm)
and high absorptivity in the NIR (650–900 nm) and UV (<400 nm) region of PBDTT-SeDPP make it a very
promising candidate for high performance tandem PSCs and visibly-transparent PSC applications.[76]
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Fig 11. (a) Chemical structures of PBDTT-FDPP, PBDTT-DPP and PBDTT-SeDPP,
(b) Absorption spectra in thin films of PBDTT-FDPP, PBDTT-DPP and PBDTT-SeDPP.
It was seen that by substituting the sulfur atoms with selenium atoms, the HOMO level increases slightly and
meanwhile the LUMO level drops a little. The narrowing of the bandgap is mainly due to the electron stabilizing
effect of selenophene moieties, since selenium is more polarizable than either sulfur or oxygen.[77,78] The
actual HOMO and LUMO energy levels of polymers are then determined by cyclic voltammetry (CV)
measurement and the results from both DFT calculation and CV measurements are summarized in the given
table. The HOMO/LUMO levels of PBDTT-FDPP, PBDTT-DPP, and PBDTT-SeDPP are measured to be
−5.26/−3.64 eV, −5.30/−3.63 eV, and −5.25/−3.70 eV, respectively. The bandgap of PBDTT-FDPP turns out to
be the smallest based on the CV testing, which conflicts with the optical bandgap
Single junction BHJ solar cell performance of these polymers were preliminarily investigated with the regular
structure of ITO/PEDOT:PSS (30 nm)/polymer:PC71BM (100 nm)/ Ca/Al under AM1.5G illumination (100
mW/cm2
). These three polymers were spin-coated onto the PEDOT:PSS coated indium-doped tin oxide (ITO)
glass substrate from DCB solution, followed by the evaporation of Ca/Al as top electrode. The optimized
polymer:PCBM ratio was found to be 1:2 by weight. Typical current density-voltage (J-V) curves are shown in
Figure , the corresponding EQE(external quantum efficiency) curves are presented in Figure 2b and the results
are summarized in Table 3
Table 3. Photovoltaic properties of single layer BHJ solar cells.
Fig 12.(a) Current density-voltage characteristics of polymer/PC71BM single junction solar cellsunder AM1.5G
illumination (100 mW/cm2
).
(b) EQEs of the corresponding devices
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The PBDTT-SeDPP based device turns out to have the lowest VOC, and it is mainly due to a relatively high
HOMO energy level. The JSC, increases from PBDTT-FDPP to PBDTT-DPP to PBDTT-SeDPP based devices.
A high JSC of 16.8 mA/cm2
was observed in PBDTT-SeDPP based devices, which is 52% and 23% higher than
PBDTT-FDPP (10.9 mA/cm 2
) and PBDTT-DPP (13.7 mA/cm2
) based devices. With an FF of around 62%, the
PBDTT-SeDPP based device shows a maximum efficiency of 7.2% (the averaged PCE from ∼40 devices is
7.0%), whereas the PBDTT-FDPP and PBDTT-DPP based devices show max/average PCEs of 4.7/4.5% and
6.5/6.4%, respectively. From the EQE results (Figure 2b), a broader coverage of PBDT-SeDPP from 300 nm to
900 nm is clearly seen. Also, the average values (note: estimated from numerical values between the two peaks
at ∼350 and ∼800 nm) are around 42%, 47% and 53% for PBDTT-FDPP, PBDTT-DPP, and PBDTT-SeDPP
based single-layer devices, respectively. It was seen that the maximum EQE for the LBG polymers (∼50%) are
still lower than the state-of-art MBG polymers such as PTB7 (∼60%).The IQE(internal quantum efficiency) of
PBDTT-SeDPP based devices was around 60%, indicating there is still significant energy loss during the
photon-to-electron conversion process.
VII. CONCLUSION
Over the past four years, OPVs have made rapid progress and its PCE has exceeded 10%. With the
development of many new donor polymers such as Bulk heterojunction (BHJ) solar cells (8-10%), Organic—
inorganic hybrid solar cells (approx 10%), Alkoxy-Substituted benzo[1,2-b:4,5-b′]dithiophene units (BDT) to
2-Alkylthienyl-Substituted BDT (8-10%), Fused Dithienogermolodithiophene low band gap polymers (7-8%)
and Selenium-Substituted Low-Bandgap Polymer (8-9%) higher PCE can be achieved. Also, further new
criteria has been established to consider a polymer as donor polymer, such as satisfying a broad absorption with
a high extinction coefficient near the region of maximum solar photon flux, a low lying HOMO energy level
and a suitable LUMO energy level. Also, it is important that the polymer has appropriate miscibility with n-type
acceptor materials. When the polymer satisfies these physical properties, the local dipole moment along the
polymer chain is critical for effective exciton separations and charge carrier generation. Apart from the
characteristics of the polymer required for high solar cell efficiency, the polymer’s photochemical stability and
the stability of donor/acceptor’s nano-morphology are crucial issues towards achieving longer lifetimes. In
addition to development of high efficiency materials, technologies must also be developed for fabricating
reasonable, lightweight and flexible devices which show the device’s lifetime suitable for commercialization. In
our view, the perspective for OPVs is very bright and is becoming brighter as the years go by.Thus Cheap
Enviorenmental Friendly Solar Energy is a key to a healthier and bright future.
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