This document summarizes a paper on achieving uninterruptible energy production in standalone power systems for telecommunications. It discusses how standalone power systems combining renewable energy sources like solar, wind, and fuel cells can provide reliable power for remote telecom equipment. However, it notes these systems still face reliability problems. The document reviews the typical failure modes of solar photovoltaic systems and wind turbines from previous studies. It recommends achieving uninterruptible energy through careful planning, using reliable components, following standards, and performing predictive maintenance informed by reliability analyses of similar systems.
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.
Advantages and recent advances of smart energy gridjournalBEEI
Smart grid is widely recognized technology used to improve the stability and losses of the electric power system. It is encouraging reliability, efficiency, and effective control of the supply of electrical energy. However, it is a hot topic for recent publications and still has a limited understanding among researchers. This review work is to provide insight and support to the beginner researchers since this topic needs a multidisciplinary background knowledge. The conventional electric transmission system and distribution networks struggle to provide resilient performance and reliable service and real-time data. Also, smart grid id a promising network maneuver to stabilize the system once any disturbances break out by using the distributed renewable energy generators, while the conventional networks lack for flexibility to integrate with renewable energy generators or microgrids. This comprehensive work is conducted to map previous controbution in a coherent manar, including the specifications, features, and fundamentals that are presented to benefit the interested readers interested in smart grid development.
AN INVESTIGATION OF THE ENERGY CONSUMPTION BY INFORMATION TECHNOLOGY EQUIPMENTSijcsit
The World Wide Web and the rise of servers and PC's data centers have become a major position in the
overall power consumption of the world. In order to prevent global warming and ensuing disasters, already
Internet-service providers, hosting providers on green power have changed. Even household energy
suppliers offer green electricity from renewable energy such as wind, solar, biomass and hydro, which
emits no carbon dioxide, to stand against global warming. Only a global change for the information
technology can prevent the global-warming. The switch to renewable energy is the beginning of our future
and must be pursued as well as the research and development in information and communication
technology.
Application of dc micro grids for integration of solar home systems in smart ...Brhamesh Alipuria
The paper discusses the application of DC micro grids and how they can be used to form smart grids which can easily incorporte solar systems. Such grids have various advantages over the existing grid infrastructure, which has been discussed at length.
If you have any questions, please write to me.
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.
Advantages and recent advances of smart energy gridjournalBEEI
Smart grid is widely recognized technology used to improve the stability and losses of the electric power system. It is encouraging reliability, efficiency, and effective control of the supply of electrical energy. However, it is a hot topic for recent publications and still has a limited understanding among researchers. This review work is to provide insight and support to the beginner researchers since this topic needs a multidisciplinary background knowledge. The conventional electric transmission system and distribution networks struggle to provide resilient performance and reliable service and real-time data. Also, smart grid id a promising network maneuver to stabilize the system once any disturbances break out by using the distributed renewable energy generators, while the conventional networks lack for flexibility to integrate with renewable energy generators or microgrids. This comprehensive work is conducted to map previous controbution in a coherent manar, including the specifications, features, and fundamentals that are presented to benefit the interested readers interested in smart grid development.
AN INVESTIGATION OF THE ENERGY CONSUMPTION BY INFORMATION TECHNOLOGY EQUIPMENTSijcsit
The World Wide Web and the rise of servers and PC's data centers have become a major position in the
overall power consumption of the world. In order to prevent global warming and ensuing disasters, already
Internet-service providers, hosting providers on green power have changed. Even household energy
suppliers offer green electricity from renewable energy such as wind, solar, biomass and hydro, which
emits no carbon dioxide, to stand against global warming. Only a global change for the information
technology can prevent the global-warming. The switch to renewable energy is the beginning of our future
and must be pursued as well as the research and development in information and communication
technology.
Application of dc micro grids for integration of solar home systems in smart ...Brhamesh Alipuria
The paper discusses the application of DC micro grids and how they can be used to form smart grids which can easily incorporte solar systems. Such grids have various advantages over the existing grid infrastructure, which has been discussed at length.
If you have any questions, please write to me.
Abstract: Energy efficiency in all the aspects of human life has become a major concern, due to significant environment impact as well as it economic importance. Information and Communication Technology (ICT) estimated 2-10% of the global consumption but is also expected to enable global energy efficiency through new technologies tightly dependent on networks. Specially, a network model based on G-network quening theory is built, which can incorporate all the important parameters of power consumption together with traditional performance metric and routing control capability. Our goal is to control both power configuration of pipeline and way to distribute traffic flow among them. Optimization policy having best tradeoff between power consumption and packet latency times. The achieved results demonstrate how the proposed model can effectively represent energy and network-aware performance indexes.
Application of the Least Square Support Vector Machine for point-to-point for...IJECEIAES
In today's industrial world, the growing capacity of renewable energy sources is a crucial factor for sustainable power generation. The application of solar photovoltaic (PV) energy sources, as a clean and safe renewable energy resource has found great attention among the consumers in the recent decades. Accurate forecasting of the generated PV power is an important task for scheduling the generators and planning the consumption patterns of customers to save electricity costs. To this end, it is necessary to develop a global model of the generated power based on the effective factors which are mainly the solar radiation intensity and the ambient weather temperature. As a result of the wide numerical range of these parameters and various weather conditions, a large training database must be used for developing the models, which results in high-computational complexity of the algorithms used for training the models. In this paper, a novel algorithm for point to point prediction of the generated power based on the least squares support vector machine (LS-SVM) has been proposed which can handle the large training database with a very fewer deal of computation and benefits from reasonable accuracy and generalization capability.
Increased demands on the nation's electrical power systems and incidences of electricity shortages, power quality problems, rolling blackouts, electricity spiked prices have caused many customers to seek other sources for high-quality and reliable electricity. Distributed Energy Resources (DER) small-scale power generation resources located close to where the electricity is used (e.g., a house or commercial sectors), provide an alternate source of energy. DER is a faster and less expensive option for the construction of large and central power plants and also high-voltage transmission lines. They offer consumers the potential for lower cost, higher service reliability, high power quality, increased energy efficiency, and energy independence. The use of renewable distributed energy generation technologies and "green power" such as wind, photovoltaic, geothermal, biomass, or hydroelectric power can also provide a significant environmental benefit.
Active and reactive power sharing in micro grid using droop control IJECEIAES
The development of renewable energy contributes to the global objectives of reducing our greenhouse gas emissions, obtaining and increasing our energy efficiency. In the face of these changes, the electric-network must adapt, while maintaining a high level of reliability and a quality of energy production. To meet this objective, it is recommended to use highly developed electrical network by integrating renewable energy sources in order to adapt the energy consumption to their production, using electrotechnical software information and telecommunications technologies. We are talking about intelligent grids (Smart Grid). The main objective of the work presented in this paper is the contribution to the study of intelligent network for efficient management of energy produced by several sources linked to the AC bus via the voltage inverters. Numerical simulations have been presented to validate the performance of the proposed active and reactive power controller (Droop Control).
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.
Sklubi AlumniWeekend 23.10.2010:
Reijo Maihaniemi
Electricity Consumption: General
Electricity Savings Through DC Power Feed
DC Data Center Projects in the World
ICT Energy saving actions
Blackout Prevention Plan – The Stability, Reliability and Security Enhancemen...Power System Operation
The stability, reliability and security of power
system are the concerned issues in Thailand due to the lessons
from the blackout around the world in 2003. Electricity
Generating Authority of Thailand (EGAT), which is responsible
on the generation and transmission system in Thailand, has
considered the measures to avoid the major power failure in
Thailand so-called the blackout prevention plan. The blackout
prevention plan is used as a tool for managing and operating the
system efficiently.
The blackout prevention plan is the preventive plan to
minimize the chance of the failure in the power system in
Thailand as possible. To identify the system vulnerability in the
network, the power system simulations are performed as the
important methodology. The power system analysis is not only
examined on the N-1 criteria but also the events from the past
experience and the potential events that can occur in the
Thailand power grid. Many aspects are analyzed to understand
the constraint on system and select the appropriate methods to
solve the problems efficiently. The investment and maintenance
cost of the solution also are taken into the account to optimize the
security of the system and economics.
Role of UPQC in Distributed Generation Power System: A Reviewijtsrd
The ever increasing share of renewable energy sources (RERs) in the todays scenario, the power grids are suffering from poor power quality due to the intermittent nature of wind and solar based power generating units. The led to extensive research in the field of power quality especially in voltage and frequency regulations Distributed generation involving RERs has become more popular in recent years due to technological advancement and has been started increasingly used in industry. It has become more important to understand the integration of these systems through PE interface with the existing electric power systems networks. At the same time, high frequency switching of Power Electronic interface has caused major Power Quality concerns, which has been tackled with the help of Custom power devices interfaces that has allowed DG to offers various benefits like ability to provide ancillary services, increased energy efficiency, increased functionality through improved power quality and voltage/VAR support, improved electrical system reliability by reducing the fault contributions, and flexibility in operations with various other DE sources. DG also allows the customer to have a choice while it reduces the overall interconnection costs. This paper focuses on widespread use of DG through various Renewable Energy Sources, Power Quality issues associated with the use of Power Electronic interface and use of various Custom Power Devices to improve Power Quality. It particularly evaluates the role of UPQC-DG in various modes of DG in following PQ standards. Sajid Bashir | Gagan Deep Yadav"Role of UPQC in Distributed Generation Power System: A Review" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-3 , April 2018, URL: http://www.ijtsrd.com/papers/ijtsrd11356.pdf http://www.ijtsrd.com/engineering/electrical-engineering/11356/role-of-upqc-in-distributed-generation-power-system-a-review/sajid-bashir
What is DERMS ? Distributed Energy Resources Management System
What is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management System
Transforming the Electricity System to Meet Future Demand and Reduce Greenhou...Gruene-it.org
Most of the world’s electricity delivery system or “grid” was built when energy was relatively inexpensive. While minor upgrades have been made to meet increasing demand, the grid still operates the way it did almost 100 years ago—energy flows over the grid from central power plants to consumers, and reliability is ensured by maintaining excess capacity.
Power Quality Parameters Measurement Techniquesidescitation
Power quality (PQ) issue has attained considerable
attention in the last decade due to large penetration of power
electronics based loads and/or microprocessor based controlled
loads. On one hand these devices introduce power quality
problem and on other hand these mal-operate due to the
induced power quality problems. PQ disturbances/events cover
a broad frequency range with significantly different magnitude
variations and can be non-stationary, thus, accurate techniques
are required to identify and classify these events/disturbances.
This paper presents a comprehensive overview of different
techniques used for PQ events’ classifications, parameters.
Various artificial intelligent techniques which are used in
PQ event classification are also discussed. Major Key issues
and challenges in classifying PQ events are critically
examined and outlined. In this paper, the main Power Quality
(PQ) problems are presented with their associated causes and
consequences. The economic impacts associated with PQ are
characterized. Finally, some solutions to mitigate the PQ
problems are presented.
Incorporating Solar Home Systems (SHS) for smart grid applicationsBrhamesh Alipuria
Solar PV systems are becoming popular for powering homes, commonly known as roof top solar plants. In this paper, various ways of connecting the solar system with the smart grids has been explored. An effective method using DC grids has been concluded after the discussion.
Abstract: Energy efficiency in all the aspects of human life has become a major concern, due to significant environment impact as well as it economic importance. Information and Communication Technology (ICT) estimated 2-10% of the global consumption but is also expected to enable global energy efficiency through new technologies tightly dependent on networks. Specially, a network model based on G-network quening theory is built, which can incorporate all the important parameters of power consumption together with traditional performance metric and routing control capability. Our goal is to control both power configuration of pipeline and way to distribute traffic flow among them. Optimization policy having best tradeoff between power consumption and packet latency times. The achieved results demonstrate how the proposed model can effectively represent energy and network-aware performance indexes.
Application of the Least Square Support Vector Machine for point-to-point for...IJECEIAES
In today's industrial world, the growing capacity of renewable energy sources is a crucial factor for sustainable power generation. The application of solar photovoltaic (PV) energy sources, as a clean and safe renewable energy resource has found great attention among the consumers in the recent decades. Accurate forecasting of the generated PV power is an important task for scheduling the generators and planning the consumption patterns of customers to save electricity costs. To this end, it is necessary to develop a global model of the generated power based on the effective factors which are mainly the solar radiation intensity and the ambient weather temperature. As a result of the wide numerical range of these parameters and various weather conditions, a large training database must be used for developing the models, which results in high-computational complexity of the algorithms used for training the models. In this paper, a novel algorithm for point to point prediction of the generated power based on the least squares support vector machine (LS-SVM) has been proposed which can handle the large training database with a very fewer deal of computation and benefits from reasonable accuracy and generalization capability.
Increased demands on the nation's electrical power systems and incidences of electricity shortages, power quality problems, rolling blackouts, electricity spiked prices have caused many customers to seek other sources for high-quality and reliable electricity. Distributed Energy Resources (DER) small-scale power generation resources located close to where the electricity is used (e.g., a house or commercial sectors), provide an alternate source of energy. DER is a faster and less expensive option for the construction of large and central power plants and also high-voltage transmission lines. They offer consumers the potential for lower cost, higher service reliability, high power quality, increased energy efficiency, and energy independence. The use of renewable distributed energy generation technologies and "green power" such as wind, photovoltaic, geothermal, biomass, or hydroelectric power can also provide a significant environmental benefit.
Active and reactive power sharing in micro grid using droop control IJECEIAES
The development of renewable energy contributes to the global objectives of reducing our greenhouse gas emissions, obtaining and increasing our energy efficiency. In the face of these changes, the electric-network must adapt, while maintaining a high level of reliability and a quality of energy production. To meet this objective, it is recommended to use highly developed electrical network by integrating renewable energy sources in order to adapt the energy consumption to their production, using electrotechnical software information and telecommunications technologies. We are talking about intelligent grids (Smart Grid). The main objective of the work presented in this paper is the contribution to the study of intelligent network for efficient management of energy produced by several sources linked to the AC bus via the voltage inverters. Numerical simulations have been presented to validate the performance of the proposed active and reactive power controller (Droop Control).
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.
Sklubi AlumniWeekend 23.10.2010:
Reijo Maihaniemi
Electricity Consumption: General
Electricity Savings Through DC Power Feed
DC Data Center Projects in the World
ICT Energy saving actions
Blackout Prevention Plan – The Stability, Reliability and Security Enhancemen...Power System Operation
The stability, reliability and security of power
system are the concerned issues in Thailand due to the lessons
from the blackout around the world in 2003. Electricity
Generating Authority of Thailand (EGAT), which is responsible
on the generation and transmission system in Thailand, has
considered the measures to avoid the major power failure in
Thailand so-called the blackout prevention plan. The blackout
prevention plan is used as a tool for managing and operating the
system efficiently.
The blackout prevention plan is the preventive plan to
minimize the chance of the failure in the power system in
Thailand as possible. To identify the system vulnerability in the
network, the power system simulations are performed as the
important methodology. The power system analysis is not only
examined on the N-1 criteria but also the events from the past
experience and the potential events that can occur in the
Thailand power grid. Many aspects are analyzed to understand
the constraint on system and select the appropriate methods to
solve the problems efficiently. The investment and maintenance
cost of the solution also are taken into the account to optimize the
security of the system and economics.
Role of UPQC in Distributed Generation Power System: A Reviewijtsrd
The ever increasing share of renewable energy sources (RERs) in the todays scenario, the power grids are suffering from poor power quality due to the intermittent nature of wind and solar based power generating units. The led to extensive research in the field of power quality especially in voltage and frequency regulations Distributed generation involving RERs has become more popular in recent years due to technological advancement and has been started increasingly used in industry. It has become more important to understand the integration of these systems through PE interface with the existing electric power systems networks. At the same time, high frequency switching of Power Electronic interface has caused major Power Quality concerns, which has been tackled with the help of Custom power devices interfaces that has allowed DG to offers various benefits like ability to provide ancillary services, increased energy efficiency, increased functionality through improved power quality and voltage/VAR support, improved electrical system reliability by reducing the fault contributions, and flexibility in operations with various other DE sources. DG also allows the customer to have a choice while it reduces the overall interconnection costs. This paper focuses on widespread use of DG through various Renewable Energy Sources, Power Quality issues associated with the use of Power Electronic interface and use of various Custom Power Devices to improve Power Quality. It particularly evaluates the role of UPQC-DG in various modes of DG in following PQ standards. Sajid Bashir | Gagan Deep Yadav"Role of UPQC in Distributed Generation Power System: A Review" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-3 , April 2018, URL: http://www.ijtsrd.com/papers/ijtsrd11356.pdf http://www.ijtsrd.com/engineering/electrical-engineering/11356/role-of-upqc-in-distributed-generation-power-system-a-review/sajid-bashir
What is DERMS ? Distributed Energy Resources Management System
What is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management System
Transforming the Electricity System to Meet Future Demand and Reduce Greenhou...Gruene-it.org
Most of the world’s electricity delivery system or “grid” was built when energy was relatively inexpensive. While minor upgrades have been made to meet increasing demand, the grid still operates the way it did almost 100 years ago—energy flows over the grid from central power plants to consumers, and reliability is ensured by maintaining excess capacity.
Power Quality Parameters Measurement Techniquesidescitation
Power quality (PQ) issue has attained considerable
attention in the last decade due to large penetration of power
electronics based loads and/or microprocessor based controlled
loads. On one hand these devices introduce power quality
problem and on other hand these mal-operate due to the
induced power quality problems. PQ disturbances/events cover
a broad frequency range with significantly different magnitude
variations and can be non-stationary, thus, accurate techniques
are required to identify and classify these events/disturbances.
This paper presents a comprehensive overview of different
techniques used for PQ events’ classifications, parameters.
Various artificial intelligent techniques which are used in
PQ event classification are also discussed. Major Key issues
and challenges in classifying PQ events are critically
examined and outlined. In this paper, the main Power Quality
(PQ) problems are presented with their associated causes and
consequences. The economic impacts associated with PQ are
characterized. Finally, some solutions to mitigate the PQ
problems are presented.
Incorporating Solar Home Systems (SHS) for smart grid applicationsBrhamesh Alipuria
Solar PV systems are becoming popular for powering homes, commonly known as roof top solar plants. In this paper, various ways of connecting the solar system with the smart grids has been explored. An effective method using DC grids has been concluded after the discussion.
Self Electricity Generation and Energy Saving By Solar Using Programmable Sys...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 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.
System operators face a proliferation of power electronics
interfaced devices such as HVDC transmission lines,
wind and solar generation in their grids. Depending on
the jurisdiction, the instantaneous share of electrical
energy produced from renewable energy sources
occasionally reaches 150%. However, to operate a power
system with sustained high levels of renewable energy,
several operational challenges need to be addressed. The
goal of this survey paper, which is one of the products
of CIGRE joint working group C2/B4.38, is to identify
such challenges. To this extend, extensive literature
review and survey among and discussions with system
operators throughout the world were performed.
This paper identified several operational challenges that
were validated by system operators. These challenges
are grouped in the following three categories: (i) new
behavior of the power system, (ii) new operation of the
power system and (iii) lack of voltage and frequency
support. For each of the identified challenge, a
description, practical examples and relevant references
are provided.
Economical and Reliable Expansion Alternative of Composite Power System under...IJECEIAES
The paper intends to select the most economical and reliable expansion alternative of a composite power system to meet the expected future load growth. In order to reduce time computational quantity, a heuristic algorithm is adopted for composite power system reliability evaluation is proposed. The proposed algorithm is based on Monte-Carlo simulation method. The reliability indices are estimated for system base case and for the case of adding peaking generation units. The least cost reserve margin for the addition of five 20MW generating units sequentially is determined. Using the proposed algorithm an increment comparison approach used to illustrate the effect of the added units on the interruption and on the annual net gain costs. A flow chart introduced to explain the basic methodology to have an adequate assessment of a power system using Monte Carlo Simulation. The IEEE RTS (24-bus, 38-line) and The Jordanian Electrical Power System (46bus and 92-line) were examined to illustrate how to make decisions in power system planning and expansions.
Micropower system optimization for the telecommunication towers based on var...IJECEIAES
This study investigates the technical and cost-effective performance of options renewable energy sources to develop a green off-grid telecommunication tower to replace diesel generators in Malaysia. For this purpose, the solar, wind, pico-hydro energy, along with diesel generators, were examined to compare. In addition, the modeling of hybrid powering systems was conducted using hybrid optimization model for energy (HOMER) simulation based on techno-economic analysis to determine the optimal economically feasible system. The optimization findings showed that the hybrid high-efficiency fixed photovoltaic (PV) system with battery followed by 2 kW pico-hydropower and battery are the optimal configurations for powering off-grid telecommunication towers in Malaysia with the lowest net present cost (NPC) and cost of energy (COE). These costs of NPC and COE are more down than diesel generator costs with battery by 17.45%, 16.45%, 15.9%, and 15.5%, respectively. Furthermore, the economic evaluation of the high-efficiency solar fixed PV panels system annual cash flow compared to the diesel generator with the battery system indicated a ten-year payback period.
Renewable energy allocation based on maximum flow modelling within a microgridIJECEIAES
This paper designs a microgrid-wide energy allocation mechanism on top of a network flow model from distributed generators to consumer entities. Basically, the flow graph consists of a set of nodes representing consumers or generators as well as a set of weighted links representing the amount of energy generation, consumer-side demand, and transmission cable capacity. The main idea lies in that a special node is added to account for the interaction with the main grid and that two-pass allocation is executed. In the first pass, the maximum flow solver decides the amount of the insufficiency, which must be supplemented by the main power network, usually with predefined cost. The second pass runs the flow solver again to fill the energy lack and calculates the surplus of renewable energy generation. The experiment result observes the stability in energy distribution over the microgrid while the amount of the total energy production can be accommodated by the maximum link capacity.
CIGRE WG “Network of the Future” Electricity Supply Systems of the futurePower System Operation
The mission of modern power systems is to
supply electric energy satisfying the following conflicting
requirements:
– High reliability and security of supply
– Most economic solution
– Best environmental protection
The first requirement of reliability and security
of supply has always been and still remains a key
objective and has shaped the design and operation
of power systems from the very beginning
of their formation. In the last few decades, the
need for a more efficient operation of the system
with the aimto reduce prices and increase the quality
of service has led to the
It is fair to say that these actions
are probably the last decade’s landmark of the
electric electric power systems framework. Inmore
recent years, the increasing concern about climate
change and the effects energy production may
have on greenhouse gas (GHG) emissions have led
to the wide integration of Renewable Energy
Sources (RES) and Dispersed Generation (DG) in
the power systemwith obvious advantages for the
environmental behaviour of the power systems.
Aggressive targets for the increased share of
renewable generation in the overall power supply
have been set, e.g. the EU Commission target
known as 20-20-20 for 2020.
Energy Demand Analysis of Telecom Towers of Nepal with Strategic Scenario Dev...IJRES Journal
Telecom towers, technically known as BTS (Base Transceiver Stations) are the most energy intensive part of cellular network architecture and contribute up to 60 to 80% of total cellular power consumption and varies in response to the real traffic demand throughout the day and night. But, thelack of grid availability highlightsa potential barrier to telecom industry growth in Nepal. Nepal has approximately 5,222 telecom towers of which about 22% do operate on diesel generators (DGs) while the remaining by grid electricity with some shares of renewable energy technologies (RETs: solar and/or wind). Despite the large carbon imprint, the uncertainty in power availability has compelled telecom operators to use DGs to ensure continuous supply of power for the better network availability, which translates huge operating costs along with adverse environmental impact. So, it becomes an imperative solution for telecom operators to evaluate all alternatives in order to increase network reliability with reduced energy cost. This study report intentionally focus on current energy consumptionof such telecom towers and forecast thefuture energydemand with reference to growing subscriber trend up to 2025 using LEAP (Long Range Energy Alternative Planning System)withBusiness As Usual (BAU) scenario. A clean energy technology (CET) scenario with possible RET options is also developed and compared with base case scenario through some policy mechanics on behalf of environmental benefits and sustainable cellular communication. Furthermore, this study concludes a potential energy cum cost saving with RET adoption with basic cost economics analysis.
Energy Demand Analysis of Telecom Towers of Nepal with Strategic Scenario Dev...IJRES Journal
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Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
1. European Association for the
Development of Renewable Energies,
Environment and Power Quality
International Conference on Renewable Energies and Power
Quality (ICREPQ’09)
Valencia (Spain), 15th to 17th April, 2009
Uninterruptible Energy Production in Standalone Power Systems for
Telecommunications
E. F. F. Ribeiro 1
, A. J. Marques Cardoso 1
and C. Boccaletti 2
1
University of Coimbra, FCTUC/IT
Department of Electrical and Computer Engineering
Pólo II – Pinhal de Marrocos, P – 3030-290, Coimbra, Portugal
Phone/Fax number: +351 239 796 232/247, e-mail: eribeiro@co.it.pt, ajmcardoso@ieee.org
2
Sapienza University of Rome
Department of Electrical Engineering
Via Eudossiana, 18, 00184 Rome, Italy
tel: (+39) -06-44585762, fax: (+39)-06-4883235, e-mail: chiara.boccaletti@ uniroma1.it
Abstract. A continuously energy production is the most
difficult and important feature to be guaranteed when
designing a standalone power system for
telecommunications. This paper focuses on a standalone
power system for telecommunications already proposed in
the literature, combining the most mature generators and
technologies related to renewable energies and environment
friendliness. It is important to know the operational
problems, the best way to solve them and how to apply
efficient maintenance. Reliability studies based on existent
applications of renewable generators (some of them used in
standalone power systems) help to know what to expect
from their operational behaviour and to reduce time and
costs in maintenance tasks. Notwithstanding their
undoubted importance, they are not much recognised in
literature, yet. The paper presents a brief review based on
the few reliability reports about wind and photovoltaic
systems available in the literature. Contributions and
important aspects are discussed having in mind all the
obstacles to achieve an uninterruptible power supply.
Key words
Standalone power systems, renewable energies,
reliability, telecommunications, uninterruptible
energy.
1. Introduction
Telecommunication has always been important for
society growth and development. It started with
smoke signals, in ancient times, and nowadays
sophisticated equipments are used thanks to the
technological progress. The world would not be as it
is without telecommunications contribution. It
assumes a basic importance in everyday life, political
issues, scientific progress, weather problems,
geographic difficulties, and many other subjects. The
impact of telecommunications equipment improvement
is huge and evident in all society activities.
All the necessary conditions to make
telecommunications equipment work properly are
achieved, not only by doing efforts in this specific area,
but also by conceiving a robust power supply unit in
order to satisfy all its requirements. The basic
prerequisites imposed to telecommunications power
systems are related to their safety, long life and
uninterruptible power [1, 2]. They all depend on a good
power system design and predictive maintenance. Other
requirements are associated to the electrical
characteristics of the telecommunications equipment,
such as nominal voltage and operational range, noise
and acceptable ripple levels.
Telecommunications networks were centred at the
Central Office in the past. At the present time, new
trends are being imposed to these networks by the
technological improvements. They are getting closer to
users and, subsequently, they are becoming dispersed.
This also means new challenges in telecommunications
power supply.
Due to recent advances in renewable energies
equipment, standalone power systems are getting more
and more suitable for this kind of applications. Besides
being generated from natural sources and, subsequently,
pollution free and naturally replenished, renewable
energies are intermittent and this represents an obstacle
to a proper telecommunications power supply. To
overcome renewable energies limitations, a standalone
power system combining different energy sources and
energy storage devices seems to be an attractive way to
supply telecommunications remote equipment in an
autonomous way. Political actions and economical
2. incentives, taking environmental concerns into
account, promote this application as the best one to
meet the telecommunications needs worldwide. In
[3], different architectures are analysed and compared
from an economical point of view, in order to get a
procedure to select the most suitable solution. It is
concluded that a gridline connection is not always the
most appropriate solution to supply remote units.
Throughout this paper, standalone power systems for
telecommunications will be presented and their
operational problems will be reviewed, based on
available reliability reports. Since uninterruptible
energy production from standalone power systems is
crucial to consider them as a suitable and reliable
solution for telecommunications powering, some
solutions are proposed to achieve it. These matters
should deserve more attention in a near future.
2. Factors influencing standalone power
systems
Several renewable sources have been through a good
development in the last decades. Therefore, their
combination would apparently provide a good
uninterruptible power system. Different renewable
generators would complement each other and energy
storage components (such as fuel cells or batteries)
would balance their discontinuous energy production.
However, a lot of requirements have to be considered
first. It is important to understand all the factors that
influence its behaviour, in order to get the best of it.
The most important factors are location, time and
user needs (power). Location associates information
about climate, energy sources availability and
environment conditions. This information is very
important to decide what kind of renewable
generators can be chosen. For example, it is
important to determine the hours of available sunlight
and average wind speed. Time is also an important
factor and two different approaches can be adopted
(long and small period). In a long period approach,
climate changes can assume a cyclical behaviour (e.g.
seasons). Also user needs might be seasonal, but this
is not the case of telecommunication systems. Instead
of following a full/empty hours scheme, they are
needed all the year long, therefore the load is
expected to be relatively constant. A detailed study of
the above factors is the first step to choose the
required standalone power system topology and to
make the best use of the local potentialities to supply
the telecommunication equipment.
3. Sizing standalone power systems
After an in-depth study and an adequate data
collection relevant to different renewable sources
available in the site, the “ideal” standalone power
system topology can be chosen. Another important
step is to size the system. A standalone power system
sizing depends on the load and on the collected
source data (potentialities of the location). Due to the
renewable energies intermittent behaviour, this kind of
systems has to be oversized. In order to avoid very high
costs, an optimization method should be used and a
really good one is described in [4] for a standalone
power system that includes wind and photovoltaic
generators and a fuel cell. It also calculates the system
initial cost.
4. Standalone power systems for
telecommunications
Renewable generators have been employed in various
applications (such as grid connection) with successful
results. The knowledge already achieved in this area can
be applied to power telecommunications equipment with
many available options to realize it [5]. Different
topologies have been successfully simulated and tested
[5-12].
A good example of a standalone power system for
telecommunications is shown in Fig. 1. When sunlight
and wind are available, photovoltaic and wind
generators produce energy to feed the
telecommunication equipment. When the generated
power exceeds the telecommunications equipment
needs, the excess power supplies the electrolyzer and
produces hydrogen until its storage is full. While wind
and photovoltaic power is not enough to supply
telecommunications equipment needs, the fuel cell
produces the required power using already stored
hydrogen.
Fig. 1. Standalone Power System [13].
3. 5. Reliability problems during
standalone power systems operation
Although requiring lesser maintenance than other
power systems (like the ones with a diesel generator,
for example) and benefiting from a good reliability,
standalone power systems are composed by fallible
units. Maintenance experience and typical failures
knowledge are critical to improve standalone power
systems reliability. Two areas would mainly benefit
from reliability studies: business and engineering.
However, there are not so many studies on this
subject available in the literature.
When planning a standalone power system, only
initial cost is usually evaluated from a business point
of view. This limited analysis is based on an
optimistic performance which does not correspond to
the actual one.
It is necessary to evaluate important factors
influencing life-cycle costs, such as operation and
maintenance costs. From an engineering point of
view, a reliability study is essential to achieve a better
performance of the standalone power system. It
provides useful information to improve component
selection and, subsequently, system design. Operation
and maintenance strategies would also benefit from
this study.
To perform a reliability study, it is necessary to
analyze a few systems with similar components. This
is the only way to achieve rigorous and useful
statistical results. For each failure and maintenance
event, performance data have to be collected, such as
system identification, dates of failure and repair, type
of event occurred and repair cost. There are different
ways for monitoring standalone power systems, such
as monthly readings or daily reports with
sophisticated instruments. Of course, they are
characterized by different accuracy and they can be
more or less cost-effective depending on the
application. Their importance is not limited to
research purposes. In fact, predictive maintenance,
which requires monitoring, is very important for
telecommunications power supply systems, in order
to achieve a continuously energy production.
Photovoltaic and wind generators are the most mature
renewable generators to be included in a standalone
power system. For this reason, a review of reliability
problems on these two kinds of generator will be
performed with reference to some studies available in
the literature. Although these kinds of reports and
studies have such a great importance, there are only a
small number of reliability reports available for
photovoltaic and wind generators.
A. Photovoltaic Systems
Photovoltaic systems are composed by two main
parts: solar modules and power conversion unit. Solar
modules are responsible for converting solar into electric
energy. In order to get the bus voltage, a power
conversion unit is necessary to be connected to them.
One of the advantages of photovoltaic generators, when
compared with other generators, is their solid-state
technology and, subsequently, easy maintenance.
Moving parts such as tracking systems (whose function
is to follow sun movement during the day with the aim
of producing as much energy as possible) are not
indispensable, however they help to get a better
performance and to reduce energy cost [14].
Due to industry efforts in module manufacturing
technology, in improving the performance and in
reducing degradation, solar modules benefit from a high
reliability [15] and their warranties last at least 20 years
[16]. Unfortunately, power conversion units show a
much lesser reliability [14-21]. Their warranty is
between 3 and 5 years. There is really a huge
discrepancy between reliability of both parts of a
photovoltaic system, which means that during solar
modules life, power conversion unit could be repaired
and replaced many times [17]. Their reliability gets even
worse if they are not designed and installed in a proper
way or if the chosen technology is not adequately tested,
which happens some times. According to [17], half of
the studied systems did not have a good performance,
long durability and a safety operation, due to an
inappropriate installation, poor design and a choice of
not certified technology.
If one component is not working in a totally healthy
way, it will affect all photovoltaic system behaviour. If
some of the solar modules fail, the whole system will
continue to work, even though energy production will
significantly reduce. Inverter failures can lead to a total
system stoppage. The most common malfunctions are
related to the fans breakdown (thermal management
system), power semiconductor (transistors, diodes) and
capacitor failures [16]. Indeed, capacitors are the most
frequent component to fail and, subsequently, the quality
of the DC bus capacitor seems to be the most critical
issue. The capacitors used in these power systems are of
the aluminium electrolytic type.
Other problems and failures related to photovoltaic
systems include disconnecting switch problems (when
fuses blown), source-circuit failures (fuse failures or
blocking diode malfunction), module problems
(damaged modules or ground problems), array wiring
troubles and direct lightning strikes.
As mechanical moving supports, tracking systems could
increase unreliability of photovoltaic systems. However,
according to [14], a lot of improvements have been
achieved and their maintenance does not seem critical.
B. Wind Systems
Wind turbine reliability is affected by the machine
design and the manufacturing process. Wind turbines are
conceived to last at least 20 years, but that is not usually
4. achieved in practice, due to deficient design,
unknown operating environment and manufacturing
control issues [22].
Wind power systems require scheduled maintenance,
such as periodic inspections, oil and filter changes,
calibration and adjustment of sensors and actuators,
blade cleaning and many other tasks specified in the
manufacturer’s manual. Although a careful planned
maintenance allows component replacing and
refurbishing, the need for unscheduled maintenance
is never totally abolished. Its drawbacks are related to
unpredictable costs and waiting time until the
components are repaired during wind conditions good
for energy production. They get even worse when
they are related to a standalone power system, since
they are located in remote sites and, subsequently,
turbine accessibility is not easy. Time to repair
damaged components is an important issue that affect
system reliability when a failure occurs. The system
will be stopped as long as the failure lasts and it
depends on repair work, spare parts availability and
human resources to handle with it. Different kinds of
failures related to different wind turbine components
will take different times to be fixed. Consistently, not
only component failures rates, but also their
downtime, are to be considered in reliability
statistical studies.
Since wind turbines are composed by complex
components, some of them are more easily prone to
fail than others. The most frequent failures are related
to gearbox and generator bearings, generator
windings, gearbox torque arms, pitch drive
electronics and power electronics converters [22].
Statistical studies confirm that the major number of
failures is associated to the electrical system,
followed by sensors and control systems [23, 24].
However, they are not responsible for the most part
of the downtime of wind power systems. Other
component failures are even more critical. For
example, gearboxes are of main concern [23, 24].
Their longest downtime when they have to be
repaired is related to their large size and hard
replacement (requiring specific equipment to be
moved, such as cranes) and the need to order spare
parts to fix them [23]. It is complicated to avoid their
breakdown, because it is mainly caused by inherent
mechanical wear. According to [23], for a typical
turbine gearbox failures account for 20% of wind
power system downtime. The average repair time is
about 256 hours.
The total number of failures in a wind power system
and their evolution according to turbine age allows to
estimate the lifetime expectancy. They allow to
compare different systems as well, as, for example,
systems with different levels of installed power.
High-power systems (above 1000 kW) have higher
annual failure rates than wind systems with lower
installed power [23]. If the evolution of failure rates
is analysed, there are also differences between high-
and low-power systems. Annual failure rates in high-
power systems seem to increase, while in low-power
systems they decrease after the first years of operation
until they reach their decaying time [23].
Improvements have been achieved in wind power
systems and they have reached an availability of 98%,
taking good planned maintenance and efficient repairs
into account. It seems to be a good result, however,
uninterruptible energy production is imperative
nowadays, in particular for telecommunication power
systems. Therefore, a vast number of challenges need to
be accomplished. For example, gearbox development
has contributed to diminish their failure rates, but repair
time seems to get longer [23].
6. Recommendations to achieve an
uninterruptible energy production in a
standalone power system
A few steps to achieve uninterruptible energy production
have already been presented and emphasized. Starting
from planning until operation problems, some
recommendations can be summarized to meet
telecommunications equipment energy needs, having in
mind all the discussed reliability problems.
Uninterruptible energy production and good reliability
in standalone power systems start with planning.
To build the standalone power system, reliable
components must be used and standards already defined
must be followed. A good infrastructure must be
accurately planned with the aim of minimizing failures
and to make as easy as possible all required maintenance
and repairs. Necessary maintenance equipments should
be also included. For example, lifting equipment should
be mounted when the standalone power system includes
wind turbines [25]. All equipment should be listed and
quantified in an inventory.
Once the system is installed and started up, it is
necessary to keep the standalone power system at its
best performance level. The cited reliability studies play
an important role. They allow to save time and money in
tasks related to maintenance. Some components that
require special attention can be identified, due to their
expensive price, repair time or criticality for the process.
Also a logistic plan including failure events and repair
tasks can be developed based on reliability studies
information.
Failure modes and their causes are also another
important matter to study. Failure mode analyses help to
prevent their evolution to a possible system shutdown or
to a catastrophic level. Failure cause analyses help to
learn from it. All failures and problems related to
standalone power systems should be faced as
opportunities for improvements.
Standalone power system maintenance should be based
in remote monitoring data. This involves a
comprehensive distribution of sensors in order to get as
much useful information as possible of the entire
5. system. Such information about performance and
operational system behaviour must be communicated
to maintenance personnel using phone lines, line-of-
sight microwave communication or satellites [25].
Robust sensors must be chosen to avoid their
malfunction. Their purpose is to spy system
behaviour and to diagnose possible failures,
preventing huge problems as soon as possible and
keeping the whole system working in a healthy way.
Another important issue to be considered in
standalone power system and responsible for many
malfunctions is vandalism. According to [19], it is
responsible for 60% of the maintenance costs of
photovoltaic standalone power systems. Therefore,
safety conditions should be guaranteed for the
standalone power systems, such as isolating it with
fences and barbed wire.
7. Conclusions
An uninterruptible energy production is the
uppermost requirement of telecommunications power
systems. It is indispensable to have a full
understanding of how standalone power systems are
influenced by external factors related to their remote
locations, to size them properly and to keep their
performance at the higher level with a suitable
maintenance. Reliability reports help in what is
concerned to maintenance and operational behaviour.
Their importance is huge and their recognition is
growing due to the standalone power system
improvements and practical experience.
In the paper, the main reliability problems are
described, according to a few number of available
reliability reports. There is still not enough
information on the subject, but it is a base to develop
important contributions to achieve the best
performance and operation of a standalone power
system. Further work should be performed. Here only
available results concerning photovoltaic and wind
generators are presented. Similar results should be
obtained for other important components, such as fuel
cells. Indeed, a lot of challenges still need to be
faced. Chemical troubles that affect fuel cells
reliability are still unknown.
As soon as standalone power systems are used in
remote sites to supply telecommunications
equipment, reliability reports should be a priority to
improve their operation, performance and design.
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