The document discusses positive temperature eutectic (PCM) thermal energy storage systems. It begins by explaining the disadvantages of conventional water-ice storage systems, which require low-temperature chillers. The document then introduces positive temperature eutectic solutions, which can freeze and melt above 0°C, overcoming these disadvantages. Various PCM mixtures are presented, along with encapsulation techniques to contain them. The document argues that PCM storage enables higher evaporator temperatures and lower condenser pressures, improving energy efficiency. A variety of applications are proposed, including utilizing chilled water and refrigeration temperature ranges for charging.
This presentation describes how use of judiciously selected Phase Change Materials can be used effectively to store energy and make it available when needed.
In a solar thermal application, typically sunlight is available in a 6-8 hour window from 8am to 4pm. However, the usage extends much beyond that. Phase Change Materials can be used to store energy for usage as required.
Development of a thermal energy storage system in a domestic environment into...Nelson García Polanco
My speech on April 27, 2015 at Energy Storage World Forum Rome, was focused on how to recover and reuse low-temperature wasted heat from kitchen appliances, and the technologies for the thermal energy storage. A full prototype of Thermal Energy Storage (TES) system was created. The TES system is based on a packed bed of macro-encapsulated phase change material (PCM). Typical household appliances were analyzed in order to evaluate the waste heat produced on the basis of the average user habits at European level.
Thermal energy storage systems store thermal energy and make it available at a later time for uses such as balancing energy supply and demand or shifting energy use from peak to off-peak hours. The document discusses several types of thermal energy storage including latent heat storage using phase change materials, sensible heat storage using temperature changes in materials, and thermo-chemical storage using chemical reactions. Case studies of thermal energy storage applications in solar plants, buildings, and cold chain transportation are also presented.
01 thermal energy storage using ice slurryWahid Mohamed
This document discusses thermal energy storage using ice slurry. It begins with an introduction to thermal energy storage, including sensible energy storage using water and latent cool storage technologies. It defines ice slurry as a suspension of ice crystals in liquid. The document outlines the components of an ice slurry generator system, including schematics of different configurations. It notes benefits like higher energy transport density and consistently cool temperatures near the phase change point. Applications include district cooling systems, and case studies demonstrate cost savings from peak shaving and improved chiller efficiency.
This document summarizes a presentation given at the 4th International Conference on Advances in Energy Research held at the Indian Institute of Technology Bombay in India on October 10, 2013. The presentation discusses enhancements to a thermal storage system for domestic use through the use of phase change material (PCM). Specifically:
- An experimental investigation of a 10 liter per day capacity thermal storage system found that including PCM occupying 26% of the volume improved the thermal storage capacity by 22% compared to a system without PCM.
- The PCM used was HS-58, which has suitable thermal properties for domestic solar water heating systems.
- Temperature time data from the experiments show that the system with PCM maintained
This document summarizes the development of an adsorption cooling system with a thermal energy storage-based evaporator for air conditioning applications. Key points include:
- The system uses zeolite 13X/CaCl2 composite adsorbent to adsorb and desorb water as the refrigerant.
- It incorporates a latent thermal energy storage system using pentadecane to reduce temperature fluctuations in the chilled water output.
- Experimental testing showed improvements over previous designs, including higher specific cooling power, lower weight, better coefficient of performance, and more stable chilled water temperatures.
- Further recommendations to optimize the system include integrating solar heating and adding nano-particles to the phase change material for improved
1. Thermal energy storage (TES) technologies like phase change materials (PCMs), sorption, and thermochemical materials can store solar and renewable heat for use when needed.
2. PCMs use the heat of phase change during melting and freezing to efficiently store and release thermal energy. Organic PCMs like paraffin wax are promising due to their high storage density and melting temperatures around human comfort levels.
3. Sorption technologies use physical or chemical bonding to store heat in materials like silica gels, zeolites, or chemical reactions. A demonstration used zeolite to store nighttime heat from district heating for use during the day.
This presentation describes how use of judiciously selected Phase Change Materials can be used effectively to store energy and make it available when needed.
In a solar thermal application, typically sunlight is available in a 6-8 hour window from 8am to 4pm. However, the usage extends much beyond that. Phase Change Materials can be used to store energy for usage as required.
Development of a thermal energy storage system in a domestic environment into...Nelson García Polanco
My speech on April 27, 2015 at Energy Storage World Forum Rome, was focused on how to recover and reuse low-temperature wasted heat from kitchen appliances, and the technologies for the thermal energy storage. A full prototype of Thermal Energy Storage (TES) system was created. The TES system is based on a packed bed of macro-encapsulated phase change material (PCM). Typical household appliances were analyzed in order to evaluate the waste heat produced on the basis of the average user habits at European level.
Thermal energy storage systems store thermal energy and make it available at a later time for uses such as balancing energy supply and demand or shifting energy use from peak to off-peak hours. The document discusses several types of thermal energy storage including latent heat storage using phase change materials, sensible heat storage using temperature changes in materials, and thermo-chemical storage using chemical reactions. Case studies of thermal energy storage applications in solar plants, buildings, and cold chain transportation are also presented.
01 thermal energy storage using ice slurryWahid Mohamed
This document discusses thermal energy storage using ice slurry. It begins with an introduction to thermal energy storage, including sensible energy storage using water and latent cool storage technologies. It defines ice slurry as a suspension of ice crystals in liquid. The document outlines the components of an ice slurry generator system, including schematics of different configurations. It notes benefits like higher energy transport density and consistently cool temperatures near the phase change point. Applications include district cooling systems, and case studies demonstrate cost savings from peak shaving and improved chiller efficiency.
This document summarizes a presentation given at the 4th International Conference on Advances in Energy Research held at the Indian Institute of Technology Bombay in India on October 10, 2013. The presentation discusses enhancements to a thermal storage system for domestic use through the use of phase change material (PCM). Specifically:
- An experimental investigation of a 10 liter per day capacity thermal storage system found that including PCM occupying 26% of the volume improved the thermal storage capacity by 22% compared to a system without PCM.
- The PCM used was HS-58, which has suitable thermal properties for domestic solar water heating systems.
- Temperature time data from the experiments show that the system with PCM maintained
This document summarizes the development of an adsorption cooling system with a thermal energy storage-based evaporator for air conditioning applications. Key points include:
- The system uses zeolite 13X/CaCl2 composite adsorbent to adsorb and desorb water as the refrigerant.
- It incorporates a latent thermal energy storage system using pentadecane to reduce temperature fluctuations in the chilled water output.
- Experimental testing showed improvements over previous designs, including higher specific cooling power, lower weight, better coefficient of performance, and more stable chilled water temperatures.
- Further recommendations to optimize the system include integrating solar heating and adding nano-particles to the phase change material for improved
1. Thermal energy storage (TES) technologies like phase change materials (PCMs), sorption, and thermochemical materials can store solar and renewable heat for use when needed.
2. PCMs use the heat of phase change during melting and freezing to efficiently store and release thermal energy. Organic PCMs like paraffin wax are promising due to their high storage density and melting temperatures around human comfort levels.
3. Sorption technologies use physical or chemical bonding to store heat in materials like silica gels, zeolites, or chemical reactions. A demonstration used zeolite to store nighttime heat from district heating for use during the day.
A review of phase change materials (pcms) for cold energy storage applicationsTAHA RAJEH
This document summarizes a review on phase change materials (PCMs) for cold energy storage applications. It discusses how PCMs can be used for cold thermal energy storage (TES) due to their high latent heat of fusion during phase change. The document outlines different types of PCMs and criteria for selecting them, including thermophysical properties like melting temperature and heat of fusion. It provides examples of common inorganic and organic PCMs and discusses techniques to improve PCMs, such as nanostructuring and encapsulation, which can increase heat transfer and thermal conductivity. The document concludes that properly selecting PCMs based on these factors is important for efficiently designing cold storage systems.
Innovative thermal energy storage technologies (Vincent O'Brien)campone
Vincent O'Brien of Copper Industries (Ireland) Ltd presented on innovative thermal energy storage technologies developed through collaborations with the University of Ulster. This included the MaxiPod thermal store, which can provide up to 38 kW of domestic hot water while maintaining temperature, and the HotHead stratifying cylinder, which exhibits increased stratification and solar collector efficiency. Copper Industries is commissioning an in-house test facility through a KTP project to characterize the performance of various thermal energy storage systems and integrate renewables with combi-systems more effectively.
Review on nanomaterials for thermal energy storage technologiesOwolabi Afolabi
This document reviews research on nanomaterials for thermal energy storage technologies. It discusses various types of phase change materials and nanomaterials that have been investigated as possible materials for efficient thermal energy storage. Nanoadditives have been used to enhance the thermal properties of phase change materials by increasing their thermal conductivity. The document outlines different classification systems for phase change materials, nanomaterials, and nanofluids/nanocomposites developed for thermal energy storage. It also reviews various synthesis methods that have been used to prepare nanofluids and nanocomposites, including one-step direct evaporation and two-step methods.
Presented by Dr. Jein Yoo, Korean Association for Energy Service Companies, KAESCO, Korea at the IEA DSM Programme workshop in Seoul, Korea on 18 April 2007.
Review on latent heat storage and problems associated with phase change mater...eSAT Journals
Abstract Energy storage devices have important role in the energy system as they minimize the mismatch between the supply and demand. This leads to improvement of the performance and the reliability of the systems. In thermal energy storage systems the Latent heat type thermal energy storages (LHTES) are attractive since they have high energy storage density and nearly isothermal operation at the phase transition temperature of the material usedthat is commonly known as phase change material (PCM). In this paper PCMs with solid-solid and solid-liquid phase transition are discussed. Though PCMs with solid-solid phase transition seem attractive due to their less stringent containment requirements but they are not widely used because of their low latent heat. PCMs with solid-liquid phase transition are the most studied and used latent heat storage materials. Those are discussed in details with their selection criterion, classification and applications. The steps involved in development of the energy storage systems and problems associated with PCMs are discussed in the next part of the paper. This will give better understanding of the latent heat storage systems to the reader. KeyWords: Latent heat storage (LHS), Phase change materials (PCM), Thermal conductivity, Thermal cycling.
This document summarizes research on thermochemical materials for heat storage. It compares different heat storage systems and discusses the principle and selection of thermochemical heat storage (THSS) materials. The characteristics of SrBr2 and MgSO4 hydrates are described based on thermal analysis. Composites of these materials with activated carbon and expanded natural graphite were manufactured and tested through multiple cycles. The composites showed stable performance over cycles but challenges remain around material stability and geometry changes during cycling. Overall, the research aims to develop low-cost thermochemical materials for seasonal heat storage applications.
This document discusses thermal energy storage using phase change materials (PCMs). PCMs can effectively store thermal energy during phase transitions from solid to liquid or vice versa, providing high energy storage density. Some commonly used PCMs are salt hydrates and hydrocarbons. Thermal energy stored as latent heat during phase changes can be 5-10 times more dense than thermal energy stored sensibly through temperature changes alone. The document outlines applications of PCM thermal storage in building insulation and solar energy systems.
A phase change material (PCM) is a substance with a high heat of fusion which, melting and solidifying at a certain temperature, is capable of storing and releasing large amounts of energy. Heat is absorbed or released when the material changes from solid to liquid and vice versa; thus, PCMs are classified as latent heat storage (LHS) units.
Challenges implementing Green Initiatives in Tall BuildingsTejwant Navalkar
We take a look at challenges in implementing Renewable Energy to meet Green Building Requirements in Tall buildings. This paper also suggests possible solutions to meet these challenges through a case study and makes a case to review the existing Green Building guidelines with respect to Renewable Energy to make to effective and socially relevant.
1) PLUSS is an Indian company that develops phase change materials (PCMs) for thermal energy storage.
2) It offers various types of PCMs, such as hydrated salts, organic PCMs, and microencapsulated PCMs, that can store large amounts of heat energy and release it at constant temperatures.
3) PLUSS has applied its PCM technologies to applications like cold storage, cold transportation, building energy efficiency, and HVAC to provide thermal energy regulation and reduce energy costs.
Thermal energy storage materials and systems for solar energy applicationsSivanjaneya Reddy
How to enhance thermal conductivity for phase change materials and selection of phase change material and about systems for solar energy application has been presented
Energia solar thermal energy storage systemsUsama Abudawud
This document provides an overview and evaluation of concentrating solar thermal energy storage systems. It finds that while two-tank molten salt storage has been proven at large scale, other technologies like thermocline and phase change material storage are yet to be demonstrated commercially. The document compares various thermal storage methods, including sensible heat, latent heat, and thermochemical storage. It provides technical details on representative technologies and evaluates their commercial readiness. The results are intended to help solar plant developers determine the best thermal storage options to increase plant flexibility and reduce electricity costs.
Thermal energy storage for buildings with PCM pelletsRamin Abhari
This document discusses using phase change material (PCM) pellets for thermal energy storage in buildings. PCM pellets are produced from paraffin wax encapsulated in high-density polyethylene to provide a stable form. Field tests show PCM pellets added to building insulation can reduce peak heat flux by 33% and net heat gain by 13%. Non-passive storage systems using PCM pellets in fixed-bed tubes are also being developed and can provide cooling capacity equivalent to 1 ton of air conditioning. The document demonstrates commercial-scale PCM production and validates the thermal performance of PCM pellets for passive building envelope applications.
Phase change materials or PCMs are compounds which store and release latent heat by changing chemical bonds through a phase alteration. These materials absorb energy during the heating and release energy to the surroundings through a reverse cooling process. The integration of PCM in textiles by coating, encapsulation or any other means has grown concentration to the scientist. In this paper; characteristics, classification, working principle of PCMs and its versatile application in textiles are mainly discussed.
A review on phase change materials & their applicationsiaemedu
The document is a review article on phase change materials (PCMs) and their applications. It discusses that PCMs can store large amounts of heat or cold in the form of latent heat during phase transition from solid to liquid or vice versa. This allows PCMs to store 2-3 times more energy per unit volume compared to sensible heat storage. The article then reviews different types of PCMs including organic, inorganic, and eutectic PCMs. Organic PCMs are further divided into paraffin and non-paraffin materials. Several properties of ideal PCMs for thermal energy storage applications are also outlined.
This document discusses different types of energy storage systems including superconducting magnetic energy storage (SMES), thermal energy storage (TES), and their applications. SMES stores energy in a superconducting coil's magnetic field and can quickly discharge stored energy back to the electric grid. TES temporarily stores thermal energy and can balance energy supply and demand. TES includes sensible heat storage using liquids, solids, or both, and latent heat storage using phase change materials. These storage systems provide benefits like clean power generation and mitigating renewable energy fluctuations.
This document discusses using phase changing materials (PCMs) for thermal energy storage. PCMs absorb heat when melting from solid to liquid at a certain temperature range, and release heat when solidifying from liquid to solid. The author proposes storing PCMs in building walls and HVAC systems to help maintain comfortable indoor temperatures and reduce energy usage. Various PCM options are described, along with encapsulation methods to control volume changes and prevent reactivity. Techniques for increasing PCM thermal conductivity, like adding metallic fillers or fins, are also summarized. The conclusion reiterates that further PCM research and system design optimization could improve energy storage efficiency.
This document discusses phase change materials (PCMs) which can store and release large amounts of thermal energy during phase transitions between solid and liquid states. PCMs provide high energy storage density with small temperature changes. Thermal energy storage methods include sensible heat storage based on temperature change and latent heat storage using phase change. PCMs are classified as organic, inorganic, or eutectic and are selected based on properties like melting temperature and thermal stability. Applications of PCMs include construction materials, textiles, food/medical packaging, and automobiles.
Investigation of solar cooker with pcm heat storageiaemedu
This document summarizes an experimental investigation of a solar cooker with phase change material (PCM) heat storage for use in high altitude places like Taif City, Saudi Arabia. The solar cooker system consists of evacuated tube solar collectors connected to a hot water storage tank. The base of the solar cooker box is connected to a copper tube heat exchanger inside a cylindrical pot filled with paraffin PCM. Hot water from the solar collectors is circulated through the heat exchanger to store thermal energy in the PCM and heat the cooking pot. Parameters like solar radiation, humidity, cooker orientation, and ambient temperature were evaluated. The study shows this system can effectively cook and heat food under high altitude conditions with partial cloud cover and moderate
PERFORMANCE STUDY OF A PHASE CHANGE MATERIAL ASSISTED SOLAR STILLIAEME Publication
A Solar still is a simple device, which is used to produce drinking water using energy of sun. Its low productivity is of great concern. Lauric acid is used as energy storage medium in the solar still to produce drinking water in the off sunshine hours. To examine the effects of use of PCM in the solar still for same total daily solar intensity on energy and exergy efficiency, experiments were carried out on two similar double slope solar still at Allahabad (250 28ꞌN, 810 54ꞌE) U.P. India. PCM is used in one of the still for the purpose of comparison with conventional still. It is observed that the exergy efficiency increases by 40% when lauric acid is used as energy storage medium in the solar still.
A review of phase change materials (pcms) for cold energy storage applicationsTAHA RAJEH
This document summarizes a review on phase change materials (PCMs) for cold energy storage applications. It discusses how PCMs can be used for cold thermal energy storage (TES) due to their high latent heat of fusion during phase change. The document outlines different types of PCMs and criteria for selecting them, including thermophysical properties like melting temperature and heat of fusion. It provides examples of common inorganic and organic PCMs and discusses techniques to improve PCMs, such as nanostructuring and encapsulation, which can increase heat transfer and thermal conductivity. The document concludes that properly selecting PCMs based on these factors is important for efficiently designing cold storage systems.
Innovative thermal energy storage technologies (Vincent O'Brien)campone
Vincent O'Brien of Copper Industries (Ireland) Ltd presented on innovative thermal energy storage technologies developed through collaborations with the University of Ulster. This included the MaxiPod thermal store, which can provide up to 38 kW of domestic hot water while maintaining temperature, and the HotHead stratifying cylinder, which exhibits increased stratification and solar collector efficiency. Copper Industries is commissioning an in-house test facility through a KTP project to characterize the performance of various thermal energy storage systems and integrate renewables with combi-systems more effectively.
Review on nanomaterials for thermal energy storage technologiesOwolabi Afolabi
This document reviews research on nanomaterials for thermal energy storage technologies. It discusses various types of phase change materials and nanomaterials that have been investigated as possible materials for efficient thermal energy storage. Nanoadditives have been used to enhance the thermal properties of phase change materials by increasing their thermal conductivity. The document outlines different classification systems for phase change materials, nanomaterials, and nanofluids/nanocomposites developed for thermal energy storage. It also reviews various synthesis methods that have been used to prepare nanofluids and nanocomposites, including one-step direct evaporation and two-step methods.
Presented by Dr. Jein Yoo, Korean Association for Energy Service Companies, KAESCO, Korea at the IEA DSM Programme workshop in Seoul, Korea on 18 April 2007.
Review on latent heat storage and problems associated with phase change mater...eSAT Journals
Abstract Energy storage devices have important role in the energy system as they minimize the mismatch between the supply and demand. This leads to improvement of the performance and the reliability of the systems. In thermal energy storage systems the Latent heat type thermal energy storages (LHTES) are attractive since they have high energy storage density and nearly isothermal operation at the phase transition temperature of the material usedthat is commonly known as phase change material (PCM). In this paper PCMs with solid-solid and solid-liquid phase transition are discussed. Though PCMs with solid-solid phase transition seem attractive due to their less stringent containment requirements but they are not widely used because of their low latent heat. PCMs with solid-liquid phase transition are the most studied and used latent heat storage materials. Those are discussed in details with their selection criterion, classification and applications. The steps involved in development of the energy storage systems and problems associated with PCMs are discussed in the next part of the paper. This will give better understanding of the latent heat storage systems to the reader. KeyWords: Latent heat storage (LHS), Phase change materials (PCM), Thermal conductivity, Thermal cycling.
This document summarizes research on thermochemical materials for heat storage. It compares different heat storage systems and discusses the principle and selection of thermochemical heat storage (THSS) materials. The characteristics of SrBr2 and MgSO4 hydrates are described based on thermal analysis. Composites of these materials with activated carbon and expanded natural graphite were manufactured and tested through multiple cycles. The composites showed stable performance over cycles but challenges remain around material stability and geometry changes during cycling. Overall, the research aims to develop low-cost thermochemical materials for seasonal heat storage applications.
This document discusses thermal energy storage using phase change materials (PCMs). PCMs can effectively store thermal energy during phase transitions from solid to liquid or vice versa, providing high energy storage density. Some commonly used PCMs are salt hydrates and hydrocarbons. Thermal energy stored as latent heat during phase changes can be 5-10 times more dense than thermal energy stored sensibly through temperature changes alone. The document outlines applications of PCM thermal storage in building insulation and solar energy systems.
A phase change material (PCM) is a substance with a high heat of fusion which, melting and solidifying at a certain temperature, is capable of storing and releasing large amounts of energy. Heat is absorbed or released when the material changes from solid to liquid and vice versa; thus, PCMs are classified as latent heat storage (LHS) units.
Challenges implementing Green Initiatives in Tall BuildingsTejwant Navalkar
We take a look at challenges in implementing Renewable Energy to meet Green Building Requirements in Tall buildings. This paper also suggests possible solutions to meet these challenges through a case study and makes a case to review the existing Green Building guidelines with respect to Renewable Energy to make to effective and socially relevant.
1) PLUSS is an Indian company that develops phase change materials (PCMs) for thermal energy storage.
2) It offers various types of PCMs, such as hydrated salts, organic PCMs, and microencapsulated PCMs, that can store large amounts of heat energy and release it at constant temperatures.
3) PLUSS has applied its PCM technologies to applications like cold storage, cold transportation, building energy efficiency, and HVAC to provide thermal energy regulation and reduce energy costs.
Thermal energy storage materials and systems for solar energy applicationsSivanjaneya Reddy
How to enhance thermal conductivity for phase change materials and selection of phase change material and about systems for solar energy application has been presented
Energia solar thermal energy storage systemsUsama Abudawud
This document provides an overview and evaluation of concentrating solar thermal energy storage systems. It finds that while two-tank molten salt storage has been proven at large scale, other technologies like thermocline and phase change material storage are yet to be demonstrated commercially. The document compares various thermal storage methods, including sensible heat, latent heat, and thermochemical storage. It provides technical details on representative technologies and evaluates their commercial readiness. The results are intended to help solar plant developers determine the best thermal storage options to increase plant flexibility and reduce electricity costs.
Thermal energy storage for buildings with PCM pelletsRamin Abhari
This document discusses using phase change material (PCM) pellets for thermal energy storage in buildings. PCM pellets are produced from paraffin wax encapsulated in high-density polyethylene to provide a stable form. Field tests show PCM pellets added to building insulation can reduce peak heat flux by 33% and net heat gain by 13%. Non-passive storage systems using PCM pellets in fixed-bed tubes are also being developed and can provide cooling capacity equivalent to 1 ton of air conditioning. The document demonstrates commercial-scale PCM production and validates the thermal performance of PCM pellets for passive building envelope applications.
Phase change materials or PCMs are compounds which store and release latent heat by changing chemical bonds through a phase alteration. These materials absorb energy during the heating and release energy to the surroundings through a reverse cooling process. The integration of PCM in textiles by coating, encapsulation or any other means has grown concentration to the scientist. In this paper; characteristics, classification, working principle of PCMs and its versatile application in textiles are mainly discussed.
A review on phase change materials & their applicationsiaemedu
The document is a review article on phase change materials (PCMs) and their applications. It discusses that PCMs can store large amounts of heat or cold in the form of latent heat during phase transition from solid to liquid or vice versa. This allows PCMs to store 2-3 times more energy per unit volume compared to sensible heat storage. The article then reviews different types of PCMs including organic, inorganic, and eutectic PCMs. Organic PCMs are further divided into paraffin and non-paraffin materials. Several properties of ideal PCMs for thermal energy storage applications are also outlined.
This document discusses different types of energy storage systems including superconducting magnetic energy storage (SMES), thermal energy storage (TES), and their applications. SMES stores energy in a superconducting coil's magnetic field and can quickly discharge stored energy back to the electric grid. TES temporarily stores thermal energy and can balance energy supply and demand. TES includes sensible heat storage using liquids, solids, or both, and latent heat storage using phase change materials. These storage systems provide benefits like clean power generation and mitigating renewable energy fluctuations.
This document discusses using phase changing materials (PCMs) for thermal energy storage. PCMs absorb heat when melting from solid to liquid at a certain temperature range, and release heat when solidifying from liquid to solid. The author proposes storing PCMs in building walls and HVAC systems to help maintain comfortable indoor temperatures and reduce energy usage. Various PCM options are described, along with encapsulation methods to control volume changes and prevent reactivity. Techniques for increasing PCM thermal conductivity, like adding metallic fillers or fins, are also summarized. The conclusion reiterates that further PCM research and system design optimization could improve energy storage efficiency.
This document discusses phase change materials (PCMs) which can store and release large amounts of thermal energy during phase transitions between solid and liquid states. PCMs provide high energy storage density with small temperature changes. Thermal energy storage methods include sensible heat storage based on temperature change and latent heat storage using phase change. PCMs are classified as organic, inorganic, or eutectic and are selected based on properties like melting temperature and thermal stability. Applications of PCMs include construction materials, textiles, food/medical packaging, and automobiles.
Investigation of solar cooker with pcm heat storageiaemedu
This document summarizes an experimental investigation of a solar cooker with phase change material (PCM) heat storage for use in high altitude places like Taif City, Saudi Arabia. The solar cooker system consists of evacuated tube solar collectors connected to a hot water storage tank. The base of the solar cooker box is connected to a copper tube heat exchanger inside a cylindrical pot filled with paraffin PCM. Hot water from the solar collectors is circulated through the heat exchanger to store thermal energy in the PCM and heat the cooking pot. Parameters like solar radiation, humidity, cooker orientation, and ambient temperature were evaluated. The study shows this system can effectively cook and heat food under high altitude conditions with partial cloud cover and moderate
PERFORMANCE STUDY OF A PHASE CHANGE MATERIAL ASSISTED SOLAR STILLIAEME Publication
A Solar still is a simple device, which is used to produce drinking water using energy of sun. Its low productivity is of great concern. Lauric acid is used as energy storage medium in the solar still to produce drinking water in the off sunshine hours. To examine the effects of use of PCM in the solar still for same total daily solar intensity on energy and exergy efficiency, experiments were carried out on two similar double slope solar still at Allahabad (250 28ꞌN, 810 54ꞌE) U.P. India. PCM is used in one of the still for the purpose of comparison with conventional still. It is observed that the exergy efficiency increases by 40% when lauric acid is used as energy storage medium in the solar still.
this power point discuses about pcm material s and recently applications on green house
and introduce kind of pcm system
this power point priority created by some other authors
This document summarizes research on integrating phase change materials (PCMs) into solar water heating systems for thermal energy storage. It reviews five studies that examined using PCMs like paraffin wax, calcium chloride hexahydrate, and sodium thiosulfate pentahydrate. The performance enhancements of PCMs include storing up to 3.45 times more energy and maintaining hot water temperatures during off-sunshine hours through latent heat release. However, flow rate affects efficiency, with lower rates providing hot water longer. Increased PCM mass also lengthens storage time but lowers charging temperatures. Overall, PCMs improve solar water heating by enabling isothermal energy storage and release.
This document discusses advancements in solar thermal walls, including zigzag Trombe walls, fluidized Trombe walls, Trombe walls with phase-change materials, composite Trombe walls, and photovoltaic Trombe walls. Zigzag Trombe walls reduce heat gain and glare using an inward V-shape. Fluidized Trombe walls improve heat transfer through a fluidized bed. Trombe walls with phase-change materials store more latent heat in a smaller space. Composite Trombe walls control heating rates and provide high insulation. Photovoltaic Trombe walls increase electrical efficiency by removing heat from photovoltaic panels.
BigWeatherGear Group and Corporate Services Brochure 2013Kristin Matson
Thank you for your interest in Bigweathergear.com Group Sales. We have been in business for over 20 years selling high quality outdoor gear. We specialize in Government, Corporate, and Group volume orders. Our staff of experts can help you fill your gear needs whether they are basic or very specific. We have custom logo applications available on most of the products we carry.
DESIGN AND DEVELOPMENT OF SOLAR WATER HEATING SYSTEM USING PHASE CHANGE MATERIALIRJET Journal
This document describes the design and development of a solar water heating system using phase change material (PCM) for thermal energy storage. It discusses selecting paraffin wax as a suitable PCM due to its melting temperature range of 45-55°C and high latent heat. The system was designed with a PCM-filled heat exchanger integrated into the solar water heating setup. Experimental results showed the PCM system increased average efficiency by 13% compared to a standard solar water heater without PCM, and kept water temperatures higher for longer periods after sunset. The prototype demonstrated the effectiveness of PCM for improving solar water heating system performance by storing thermal energy for use when solar radiation is unavailable.
A development and performance evaluation of a two-stage cascade refrigeration system for ice block production was carried out in this work. Two single stage vapour compression refrigeration systems were thermally coupled. The cascade refrigeration system thus formed enhances cooling effect and fast track ice production. This machine was designed for a refrigeration capacity of 3kW to achieve the conversion of 128.25m3 of water at 300C to ice block at -150C using R407A/R410A as working fluids. Experimental test of the machine was conducted under fixed and variable load conditions with the temperature and pressure both at the inlet and exit of each of evaporator, compressor and condenser taken. From the data obtained the refrigerating effect, COP and overall efficiency were determined. The result of the performance evaluation shows that as the evaporator temperature increases from -150C to -30C keeping the temperature difference in the cascade condenser and condenser temperature constant, the refrigerating effect increases from 189.17kJ/kg to 201.34kJ/kg, the COP increases from 4.13 to 6.90 and the overall efficiency of the system increases from 61.03% to 64.27%. As the condenser temperature increases from 400C to 490C keeping the evaporator temperature and temperature difference in the cascade condenser constant, the refrigerating effect decreases from 189.17kJ/kg to 184.37kJ/kg, the COP decreases from 4.13 to 3.80 and the overall efficiency of the system decreases from 61.03% to 50.92%. However, as the temperature difference in the cascade condenser decreases from 60C to 20C keeping the evaporator and condenser temperature constant, the refrigerating effect increases from 190.76kJ/kg to 197.06kJ/kg, the COP increases from 4.18 to 4.62 and the overall efficiency of the system increases from 60.64% to 63.25%. The machine achieved the designed condition in six (6) hours and the ice blocks so produced retained its solid state for 48 hours with the cover remained closed which denote a very impressive transformation capacity and reliability of the device compare with other homemade.
This document describes the design and fabrication of a solar powered lithium bromide vapor absorption refrigeration system. It uses lithium bromide and water as the working fluids, with solar energy powering the generator to separate the water vapor from the lithium bromide solution. The water vapor then condenses and evaporates to provide cooling, while the strong lithium bromide solution absorbs the water vapor back into a weak solution to complete the cycle. The document provides details on the system components, operating principles, and achievable COP between 0.7-0.8 using this environmentally friendly solar powered system.
Hydrogen production by a thermally integrated ATR based fuel processorAntonio Ricca
A compact auto-thermal reforming (ATR) based fuel processor was designed to produce 10 Nm3/h of hydrogen from methane and natural gas. Preliminary tests showed the ATR system could sustain high feed rates and natural gas was only weakly inhibited. The water-gas shift (WGS) catalyst tested was not optimal as it performed far from equilibrium and limited carbon monoxide conversion. Further work is needed to optimize the WGS catalyst, recover heat from the WGS exhaust, scale up the system to 50-100 Nm3/h of hydrogen production.
This document provides an overview of solar air conditioning technologies and best practice examples from several European countries. It describes two main types of solar cooling systems: chilled water systems and open cycle desiccant cooling systems. Chilled water systems use absorption or adsorption chillers to produce chilled water for air conditioning, while open cycle systems directly condition the supply air. The document outlines the technologies used in small and medium sized solar cooling applications and provides examples of installed systems in Austria, France, Germany, Greece, Italy, Portugal, and Spain.
The document describes experimental studies of two cylindrical latent heat energy storage systems (LHESS) using lauric acid as the phase change material (PCM). The first is a horizontal cylinder with one finned copper pipe passing through the center. The second is a vertical cylinder with two finned copper pipes allowing for simultaneous charging and discharging. Experiments were conducted to study the phase change behavior of the PCM and heat transfer processes during charging, discharging, and simultaneous charging/discharging. Results show natural convection plays an important role in melting and simultaneous charging/discharging but less so in solidification.
Reduction of cold start emissions in automotive catalytic converter using the...Asheesh Padiyar
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PCM Thermal Energy Storage Systems; Ashrae 2004 Conference Paper
1. VENUE
ASHRAE 2004, ANAHEIM WINTER MEETING
TITLE
POSITIVE TEMPERATURE EUTECTIC (PCM)
THERMAL ENERGY STORAGE SYSTEMS
AUTHORS
Zafer URE M.Sc., C.Eng., MCIBSE, MASHRAE, M.Inst.R, MIIR
Environmental Process Systems Limited
Unit 32, Mere View Industrial Estate, Yaxley, Cambridgeshire, PE7 3HS, U.K.
Tel: +44-(0)-1733 243400, Fax: +44-(0)-1733 243344,
e-mail: z.ure@epsltd.co.uk, www.epsltd.co.uk
Synopsis;
Thermal Energy Storage (TES) may be considered as a useful tool to reduce the
number of refrigeration machinery by means of spreading the daytime load over
24 hours period. Hence, any type of TES systems can be consider as useful tool to
reduce the overall environmental impact for a given cooling application.
Water / Ice TES has the advantage of universal availability, low cost and transport
ability through other system components. However, a conventional water based
TES system for air conditioning application requires low temperature chillers and
therefore standard water chillers must be replaced with low temperature glycol
chillers which operate with a lower evaporation temperature.
The disadvantages of a conventional HVAC chiller and ice (water ice) storage
system can be overcome by utilising the latent heat capacity of various “Eutectic”
mixtures without the need for minus circulation temperatures. Plus temperature
thermal energy storage PlusICE not only enables the designer to utilise existing
chiller technology, but also this technique enables charging process to take place
possibly by means of free cooling, i.e. without running the chillers.
This paper is extended to investigate the alternative TES systems in the form of
Eutectic PlusICE Solutions. The results of performance tests for various
temperature ranges as well as the practical application guidance are also
incorporated as part of this paper.
Keywords;
(C.O.P) Co-efficiency of Performance, (TES) Thermal Energy Storage
(HVAC) Heating Ventilation Air Conditioning,
(PCM) Phase Change Materials, Eutectic, PlusICE , CO2 Carbon Dioxide
ASHRAE-2004-4.doc
2. 1.0 - BACKGROUND
Energy usage, economical and environmental issues are becoming the focal points for both
end users and the public at large. Current trends towards privatisation and an open market
approach for utility companies has created a new kind of energy market whereby the period of
energy usage and the type of energy used is becoming the main criteria for price structuring (1 )
rather than overall energy consumption.
Hence, current building services must be designed to provide sufficient flexibility for load
shifting and energy usage control in order to achieve the most economical operation. A
Thermal Energy Storage technique whereby " Storing High or Low Temperature energy
for later use in order to bridge the time gap between energy availability and energy use "
can be considered as a useful tool to achieve this aim.
Unfortunately HVAC & Refrigeration TES applications utilise water ice which can only be
produced with low temperature chillers. As a result, the benefits of night time low ambient
temperature, existing water chillers and possibly free ambient cooling options cannot be fully
utilised.
If we can offer designers ICE which freezes and melts above 0°C (32 °F) this product will
open new horizons for environmentally friendly and economical systems for both New and
Retrofit type process cooling / heating load shifting applications.
This paper investigates Positive Temperature Eutectic Solutions for long term TES usage to
achieve the above aim. Relevant application guidance along with typical application
examples are also incorporated within this paper.
2.0 - THERMAL ENERGY STORAGE:
Thermal Energy Storage bridges the time gap between energy requirement and energy use. A
thermal storage application may involve a 24 hour or alternatively a weekly or seasonal
storage cycle depending on the system design requirements. Whilst the output is always
thermal, the input energy may be either thermal or electrical.
In full storage systems, the entire design load for the design day is generated off peak and
stored for use during the following peak period. In partial storage systems, only a portion of
the daily load is generated during the previous off peak period and put into storage. During
the peak period, the load is satisfied by a simultaneous balancing operation of the installed
machinery and stored energy in order to satisfy the overall daily design duty.
2.1 - Storage Medium:
For HVAC and refrigeration application purposes, water and phase change materials (PCM)
constitute the principal storage media. Water has the advantage of universal availability, low
cost and transport ability through other system components. However, a conventional water
based TES system for air conditioning applications require low temperature chillers and
therefore standard water chillers must be replaced with low temperature glycol chillers which
operate at lower evaporation temperatures ( 2 ) .
ASHRAE-2004-4.doc
3. 2.2 Current Ice Production Technology :
Ice production techniques can be divided into two main groups namely Dynamic and Static
systems ( 3 ) as shown in Table 2.2.1. The ice produced can be used either directly to chill
products such as fish, vegetables, meat, poultry etc. or indirectly as a secondary coolant for a
latent heat cooling effect for process cooling such as ice storage, TES systems for air
conditioning and process cooling as a secondary cooling medium.
STATIC ICE PRODUCTION DYNAMIC ICE PRODUCTION
1 - Ice Builders 1 - Plate Harvester
2 - Ice Banks 2 - Tube Harvester
3 – Encapsulated Ice Modules 3 - Flake Ice Machines
a) Balls 4 - Binary Ice Machines
b) Flat Containers
Table 2.2.1 - Current Ice Production Technology
3 - POSITIVE TEMPERATURE EUTECTIC TES SYSTEMS :
Positive Temperature Eutectic Solutions are mixtures of two or more chemicals which, when
mixed in a particular ratio, have a freezing / melting point above water freezing temperature of
0°C (32 °F) and they offer a thermal energy storage facility between +4 °C (39 °F) and +117
°C (242 °F).
Eutectics are well-known and in fact early applications date back to the late 18th century
however the separation and the life expectancy of these mixtures were unpredictable and
therefore their wide spread usage was limited.
The disadvantages of a conventional HVAC chiller and ice (water ice) storage system can be
overcome by utilising the latent heat capacity of various “Eutectic” mixtures without the need
for minus circulation temperatures.
Positive temperature thermal energy storage “PlusICE” not only enables the designer to
utilise existing chiller technology but also enables charging by means of free cooling ( 4 ) , i.e.
without running the chillers
Although the term “Eutectic” is widely used to describe the materials we are interested in, a
better description would be “Phase Change Materials” (“PCMs”). Unfortunately, very few of
the documented PCMs (a number of which are listed in Table 3.1) (5) are true Eutectics and
so many have to be modified to obtain a material suitable for long term use.
ASHRAE-2004-4.doc
4. Material Melt Heat of Latent
Point Fusion Heat
(ºC) ( ºF) kJ/kg Btu/Lb MJ/m3 Btu/Lb
MgCl2.6H2O 117 243 169 73 242 6,499
Mg(NO3)2.6H2O 89 192 163 70 252 6,768
CH3COONa.3H2O 58 136 226 97 287 7,708
MgCl2.6H2O/ 58 136 132 57 201 6,499
Mg(NO3)2.6H2O
Na2HPO4.12H2O 34 93 265 114 379 10,179
Na2SO4.10H2O 32 90 251 108 335 8,997
Na2CO3.10H2O 32 90 233 100 340 9,131
Waxes 28 to 82 to 220 to 94 to 170 to 4,564
4 39 245 105 195 to
5,237
Polyethylene 28 to 82 to 146 to 62 to 165 to 4,431
glycols -15 -9 155 66 175 to
4,699
CaCl2.6H2O 27 81 191 82 298 8,003
Glauber’s salt + 24 to 75 to wide wide wide wide
additives 4 39 range range range range
CaCl2.6H2O/ 15 59 140 60 249 6,687
CaBr2.6H2O
Water 0 32 335 144 335 8,997
Range of 0 to 32 to Wider Wider wide wide
water/salt -64 -83 range range range range
Eutectics
Table 3.1 - Range of commonly used PCMs
PCMs can be broadly grouped into two categories; ”Organic Compounds“ (such as
polyethylene glycol) and “Salt-based Products” (such as Glauber’s salt). Each group of
PCMs comes with advantages and disadvantages some of which are listed in Table 3.2 ( 4 ).
Advantages Disadvantages
Simple to use Generally more expensive
Non-corrosive Lower latent heat/density
No supercooling Often give quite broad melting range
ORGANIC No nucleating agent Can be combustible
Generally cheap Need careful preparation
Good latent heat/density Need additives to stabilise for long
Well defined phase change term use
SALT-BASED temperature Prone to supercooling
Non-flammable Can be corrosive to some metals
Table 3.2 - Characteristics of PCMs
ASHRAE-2004-4.doc
5. The fundamental requirement for a Modified Eutectic Solution can be classified in three
categories, namely stable solution ( no separation or degrading), minimum supercooling /
heating and finally close freezing and melting temperatures as illustrated in Figure 3.1.
Freezing Curve Melting Curve
Temperature
Freezing &
Melting Region
(2)
(1)
Super Cooling/
Heating Zone
Time
Figure 3.1 - Eutectic PCM Freezing / Melting Curve
There are three fundamental additives commonly used to modify Eutectic solutions covered
in Table 3.1 for long term use. The first additive is Nucleating Agentx which encourages
Crystal formation and therefore minimises super cooling and the second additive is Freeze
Depressant to achieve a lower phase change temperature/.The third and final additive is the
Gelling / Thickening Agent in order to overcome separation and degrading problems.
Once the above components have been carefully applied, a satisfactory Eutectic Solution can
be produced from the physical and thermodynamic point of views and commercially available
solutions are incorporated in Table 3.3.
However, majority of suitable PCM solutions for HVAC and refrigeration systems are
corrosive to commonly used pipe and line components and therefore a suitable encapsulation
techniques must be applied to overcome this problem while providing the best thermal
performance. Various encapsulation techniques such as tube, flat container or alternatively
ball concepts have been developed whereby the PCM solution is encapsulated in plastic and /
or metal shell as illustrated in Figure 4.2 (4 ).
llaB
llaB lleC
lleC maeB
maeB
EPIP RENNI
LAES LACINAHCEM
NOITULOS CITCETUE
EBUT RETUO
NRUTER
Figure 4.2 - PlusICE PCM Beam Concept
ASHRAE-2004-4.doc
6. The heat transfer between the surrounding media, which flows around or inside the unit and
the surrounding PCM solutions, takes place from the outer or inner or the combination of
both surfaces of the encapsulated PCM unit. These techniques are generally eliminates the
contamination risk and offers an efficient, cost effective, practical and flexible new type of
TES designs.
5 - TES AND ASSOCIATED ENERGY EFFICIENCY:
Irrespective of the type of refrigerant used, it is vital to improve the energy efficiency for any
given refrigeration system in order to achieve an environmentally friendly design. Every
compression refrigeration cycle operates between the discharge and suction pressure
envelope, which dictates the cycle shown in Figure 5.1.
BASIC REFRIGERATION CYCLE
PRESSURE (Barg)
Pc SUB-COOLING CONDENSER
EXPANSION
VALVE COMPRESSOR
Pe
SUPER -HEATING
EVAPORATOR
ENTHALPHY (KJ/kg)
Figure 5.1- Cardinal Rule for the Refrigeration Energy Efficiency
The efficiency of the cycle can be improved by utilising different types of refrigerant,
compressor, condensing, evaporating and expansion devices, but the cardinal rule of energy
efficiency dictates that “lower condensing pressures and higher evaporation temperatures
lead to less energy consumption for a given refrigeration duty” therefore designers should
aim to achieve the above requirement within the design limits for a given system.
If a Positive Temperature Eutectic Thermal Energy Storage system is incorporated as part of
the cycle, it offers the following energy efficiency features;
* Higher evaporation temperature during TES charging leads to less power consumption.
* Lower condensing pressure reduces the compressor power consumption.
* Free sub-cooling TES increases the cooling capacity and the overall COP.
* Superheat control TES improves the compressor operation.
* Lower nighttime ambient conditions may offer free TES charging.
ASHRAE-2004-4.doc
7. 6.0 - PlusICE APPLICATIONS ;
Positive Temperature Eutectic Solutions between +4 °C and +117 °C can not only be charged
using conventional water chillers and the temperature range also offers the following
additional TES applications for a cost effective energy management concept for both New
and Retrofit type process cooling / heating load shifting applications.;
* Absorption & Co-Generation.
* Cooling Tower / Dry Cooler Circuit Load Shifting.
* Heat Recovery / Solar Heating Systems.
• Free Ambient Cooling Circuit.
The beam design shown in Figure 4.3 can be filled with any of the proposed PCM solutions
in Table 4.1. The positive temperatures offered by this concept opens a revolutionary new
way of thermal energy storage whereby designers can utilise conventional chilled water and
refrigeration temperature ranges to charge the TES system.
Furthermore, the heat rejection side of the refrigeration cycle, free cooling and heat recovery
TES concepts can also be incorporated in order to minimise the maximum demand charges
and energy consumption of the system.
A possible combination of the proposed beam concept for both HVAC and refrigeration side
of the system is incorporated in Figure 6.1 ( 4 ).
V VV V PlusICE Concept
PlusICE
Condenser
HEAT
REJECTION
SYSTEM
Condenser Water
Chiller
Receiver
Receiver
Compressor
HVAC Evaporator
Evaporator
Figure 6.1 - PlusICE PCM Beam Applications
ASHRAE-2004-4.doc
8. A carefully balanced positive temperature thermal energy storage system enables designers to
control the refrigeration envelope shown in Figure 5.1 and therefore the size of the
refrigeration machinery can be reduced as a result of an optimum energy balance.
In particular, the possibility of a Free Cooling Circuit, Absorption chillers ( 6 ) , Co-
Generation, Solar ( 7 ), Hot Water and Heat Recovery TES charging may result in further
reduction of refrigeration machinery and unmatched cost effective TES installations for both
new and retrofit applications.
The relevant positive temperature TES against a conventional low temperature chiller Ice
Storage charging operations are illustrated for Air and Water Cooled chiller operations over
a range of operating temperatures in Figure 6.2 and Figure 6.3 respectively.
20 25 30 35 40 45
Ambient Air Temperature (C)
4.50
PlusICE CH ARGING
4.00
DAY CHILL ER
ICE BUILD
Chiller COP
3.50
3.00
2.50
2.00
4 0 -2 -4 -6 -8
Glycol Le aving Te m pe ratur e (C)
Figure 6.2 - Air Cooled Chiller PlusICE Vs Conventional Ice Charging Comparison
30 35 40 45 50 52
5.00
C ondenser Leaving W ater Temperature (C )
4.50 PlusICE CH ARG ING
4.00
Chiller COP
DA Y CH IL L ER
ICE B U IL D
3.50
3.00
2.50
2.00
4 0 -2 -4 -6 -8 -10
Glycol Leaving Temperature (C)
Figure 6.3 - Water Cooled Chiller PlusICE Vs Conventional Ice Charging Comparison
ASHRAE-2004-4.doc
9. Low ambient temperatures coupled with higher evaporation temperatures offer a significant
overall COP improvement, which is in the region of 16-46 % depending on the type of unit
and location. A similar benefit can also be achieved if we apply a Positive Temperature TES
for the high temperature i.e. heat rejection side of the system. A conventional design must
cater for the peak ambient conditions which occur only a few days or weeks of the year (8).
Typical UK annual average daily wet and dry bulb temperatures as well as standard design
levels are illustrated in Figure 6.4 ( 9 ).
30
28
26
24
22
Temperature (Deg C)
20
18
16
14
12
10
8
6
4
2
0
JAN
FEB
M AR
APR
M AY
JU NE
JULY
L O N D O N (U K ), AUG
SEP
AVERAGE W EATHER DATA, OCT
(K ew 1 9 4 1 -7 0 ) NO V
DEC
W e t B u lb D r y B u lb D e s ig n
Figure 6.4 - Typical UK Annual Average Ambient Profile Vs Design Ambient
Considering the refrigeration envelope indicated in Figure 5.1, Dry Cooler / Cooling Tower
circuit Heat Rejection TES can be charged by simply utilising low ambient temperatures and
this free charging operation offers a significant energy and load shifting facility by controlling
the Heat Rejection side of the system i.e. Condensing Pressure and effectively controlling the
refrigeration machinery’s energy consumption.
This principal can be applied to both Mechanical Compression and Heat Driven systems and
Figure 6.5 illustrates a typical Heat Rejection TES operation for a water cooled chiller and the
study indicates that the day time peak energy consumption can be reduced by as much as
33% simple by utilising the night time low ambient. In other words, the day COP
improvement can be achieved without running any refrigeration machinery over night. As a
result, a heat rejection TES offers unmatched efficiency, reduced running cost and an
environmentally friendly concept.
ASHRAE-2004-4.doc
10. 30 35 40 45 50 52
C ondenser L eaving W ater T em perature (C )
5.00
4.50 3
4.00
C hiller D ay O peration
Chiller COP
2
3.50 1
3.00
2.50
2.00
4 0 -2 -4 -6 -8 -10
Glycol Le aving Te m pe rature (C)
C O P Im provem en t b y P lu sIC E T E S L oad S hifting
ent h ifting
1) 5 o C R E D U C T IO N 13 % C O P IM P R O V E M E N T
2) 10 o C R E D U C T IO N 23 % C O P IM P R O V E M E N T
3) 15 o C R E D U C T IO N 33 % C O P IM P R O V E M E N T
Figure 6.5 - Water Cooled Chiller PlusICE Heat Rejection TES Impact on COP.
7.0 - CONCLUSION:
Modern society’s reliance on refrigeration and air conditioning indicates that refrigeration and
the associated environmental issues will be with us for a considerable time and therefore one
has to utilise existing and available alternative technologies with minimum usage of energy.
A Positive Temperature Eutectic “ PlusICE “ Thermal Energy Storage not only provides the
end user with an Environmentally Friendly design but also the following additional benefits
can be obtained:
• Reduced Equipment Size
• Capital Cost Saving
• Energy Cost Saving
• Environmentally Friendly Installation
• Improved System Operation
• Flexibility for the Future Capacities
The temperature ranges offered by the proposed PCM solutions utilise conventional chilled
water temperature ranges for both the charging and discharging sides of the system. Hence,
they can be applied to any new or retrofit application with minimal technical and economical
impacts.
Furthermore, the possibility of Free Cooling Cycle, Absorption Chillers, Co-Generation,
Solar, Hot Water and Heat Recovery TES system combinations offer new horizons for
designers to control the energy balance to match the load and electricity demand /
consumption of the system as a whole.
The task for designers is to explore all available technologies towards achieving improved
efficiency regardless of which refrigerant is used, and apply where and when possible
diversification technologies in order to minimise the overall CO2 emission related to energy
usage. A carefully balanced PlusICE Thermal Energy Storage may be the answer for some of
the cooling applications for an Environmentally Friendly and Economical alternative.
ASHRAE-2004-4.doc
11. 8.0 - REFERENCES:
1- Beggs C., Ure Z . “Environmental Benefits of Ice TES in Retailing Application”,
CIBSE / ASHRAE Joint National Conference, Part II, Harrogate, Sep. 1996, UK
2- Ure Z . “Thermal Energy Storage in Retailing Application”, CIBSE / ASHRAE
Joint National Conference, Part II, Harrogate, Sep. 1996, UK
3- Ure Z., “Alternative Technology”, Page 20-22, October 1996 Partners in Europe
Issue, RAC Journal
4- Burton G, Ure Z . “Eutectic Thermal Energy Storage Systems” , CIBSE National
Conference, Volume II, Alexandra Palace, Oct. 1997, UK
5- ASHRAE Handbook, “HVAC Systems and Applications “, Issue : 1987, Section 46
6- Ames, D.A., Eutectic Cool Storage: Current Developments, ASHRAE Journal,
April 1990
7- Telkes, M., Solar Energy Storage, ASHRAE Journal, September 1974
8- “Design Ambient Temperatures”, Refrigeration Industry Board, 1985
9- Met Office Data
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