Retail supermarkets are responsible for around 3% of total electrical energy consumed in the Unit... more Retail supermarkets are responsible for around 3% of total electrical energy consumed in the United Kingdom and the most energy is used in refrigeration systems, particularly for operation of open displays such as delicatessen cabinets which consume approximately 50%. Although the cabinets are energy intensive, they are commonly used in supermarkets for displaying unwrapped chilled food stuffs. These cabinets are associated with the weight loss and quality deterioration of food stuffs being reported frequently as the cause for their high operational costs. This paper presents an investigation on the cause and rectification of weight loss in delicatessen cabinets. Specifically, the paper describes the effective use of low emissivity glass in reducing the impact of the thermal infrared radiation on the food temperatures and energy consumption.
This paper presents a feasibility study of the technical and economic viability of introducing co... more This paper presents a feasibility study of the technical and economic viability of introducing combined heating and cooling networks, referred to collectively in this paper as “thermal networks”. The steps used for this study include the identification of the most viable thermal network configuration, followed by analysis of a number of potential building mix scenarios and estimation of their respective potential impact on energy consumption, carbon emissions and economics. The final step was a discussion of the potential benefits and drawbacks associated with the implementation of the selected thermal network. This study revealed that by utilising thermal networks, with central energy centres, approximately 1831 tonnes of CO2 could be saved per annum compared to traditional supply methods. With a minimum assumed system life of 25 years this equates to approximately 46000 tonnes CO2. It has also been identified that, in conjunction with a marginal shift in policy to encourage an inc...
This paper presents the results of a study carried out at London South Bank University into how c... more This paper presents the results of a study carried out at London South Bank University into how current electrical power generation and storage technologies might be integrated with advanced energy management systems to achieve zero carbon dwellings to 2016 (implementation of the Code for Sustainable Homes (CSH) Level-6) and beyond. Whereas thermal energy demands of buildings are tending to decrease as they become more thermally efficient, electrical energy demands for dwellings are unlikely to decrease significantly, because the increasing efficiency of electrical equipment and appliances tends to be offset by higher levels of ownership and utilization. Baseline energy demand profiles were developed for a range of typical dwellings built to Part L 2006 building standards [1] and then used to predict the energy demand for similar dwellings if built in 2016 to CSH Level-6 [2,3]. A renewable electrical power generation and storage model was developed and used with the electrical energ...
“Modelling and Performance Evaluation of a Low Temperature Ammonia-Water Absorption Refrigeration... more “Modelling and Performance Evaluation of a Low Temperature Ammonia-Water Absorption Refrigeration System”, Energy Conversion and Management, 2008.
Food retail supermarkets consume significant amounts of energy with large supermarkets accounting... more Food retail supermarkets consume significant amounts of energy with large supermarkets accounting for up to 5% of the total energy consumption in developed countries. A major opportunity to reduce energy consumption in this sector is to employ local Combined Heat and Power (CHP) generation systems. However, the lower heat demand of supermarkets has hindered the full utilisation of localized CHP generation systems in this sector. A way of overcoming this is to convert the heat energy from the CHP unit into another form that is continuously required by the supermarkets instead of dumping it. This could be done by integrating the CHP unit with low temperature heat driven absorption chillers forming a trigeneration system that will provide electrical power, heating and refrigeration to the supermarket throughout the year. This paper presents an assessment of tri-generation technology for use in a 30,000 ft 2 food retail supermarkets, based on 80 kWe modular micro gas turbine (MGT) CHP p...
Environmental footprinting is widely used in the academic, industrial and political circles alike... more Environmental footprinting is widely used in the academic, industrial and political circles alike. But it is in the product centric category of environmental footprinting techniques that Product Carbon Footprint (PCF) and Life Cycle Assessment (LCA) emerged as pivotal instruments in response to the climate change and sustainability imperatives. In addition, these techniques have been the object of several international assessment guidelines and according to Carbonostics (2011) and Fishwick (2012) they can be evaluated in terms of international acceptance, time/cost involvement and comparability. In contrast, little literature discusses the dissimilarities inherent in the use of different environmental measurements for an identical product. That is the reason why this paper presents a comparison between the results obtained from a Product Carbon Footprint (PCF) against that of Life Cycle Assessment (LCA) for an identical Refrigerated Display Cabinets (RDC). Results of the study show ...
The Centre for Efficient and Renewable Energy in Buildings (CEREB) is a unique, teaching, researc... more The Centre for Efficient and Renewable Energy in Buildings (CEREB) is a unique, teaching, research and demonstration resource for the built environment. It is located at London South Bank University (LSBU) and showcases different renewable and low carbon energy solutions for which performance data is captured for teaching and research. The technologies included are Ground Source Heat Pump (GSHP) for providing heating and cooling to the 8,500 m 2 K2 building which is located below CEREB. The solar thermal collectors are used to provide the hot water demand of the K2 building, with back-up boilers to supplement the required heat on cloudy days. The centre itself has additional technologies including solar fibre optic lighting, solar Photovoltaic (PV) panels, solar thermal tubes (evacuated tubes), phase change materials, absorption chiller for cooling, and a weather station, which is crucial for researching the technologies. This paper consists of two parts; the first part presents a b...
The discharge temperature of CO 2 transcritical system can provide high grade heat that can be re... more The discharge temperature of CO 2 transcritical system can provide high grade heat that can be reclaim and re-use for hot water services, space heating and cooling systems. This paper investigates the performance of an innovative booster R-744 system with heat recovery at different operating conditions based on its mathematical EES model which includes the variation of the cooling capacities of different size of stores, discharge pressures, receiver pressure and superheats.
This presentation describes the work undertaken by the IIR Working Party and the results achieved... more This presentation describes the work undertaken by the IIR Working Party and the results achieved, including the information on refrigerant leakage and containment that has been collected, collated, and categorized. The availability of such information on the IIR’s FRIDOC database and gaps in current knowledge are also discussed. A new IIR Informatory Note on refrigerant emissions is presented.
Global warming and the urban heat island effect in large towns and cities demand new approaches t... more Global warming and the urban heat island effect in large towns and cities demand new approaches to cooling buildings in an efficient and sustainable way. Modern refrigeration, air conditioning and heat pump (RACHP) systems can achieve a high coefficient of performance and low direct emissions (through reduced refrigerant leakage and the use of low global warming potential alternatives), but refrigeration technology already accounts for around 15% of worldwide electricity use and up to 10% of all greenhouse gas emissions, so in the context of international agreements to reduce global greenhouse gas emissions by up to 80%, RACHP systems alone cannot provide a sustainable cooling solution for cities. The purpose of the model described in this paper is to provide a simple and easy to use tool to estimate the impact of different RACHP technologies, alternative building design and operating parameters and future global warming, on the energy demands and carbon emissions of buildings. This...
Retail supermarkets are responsible for around 3% of total electrical energy consumed in the Unit... more Retail supermarkets are responsible for around 3% of total electrical energy consumed in the United Kingdom and the most energy is used in refrigeration systems, particularly for operation of open displays such as delicatessen cabinets which consume approximately 50%. Although the cabinets are energy intensive, they are commonly used in supermarkets for displaying unwrapped chilled food stuffs. These cabinets are associated with the weight loss and quality deterioration of food stuffs being reported frequently as the cause for their high operational costs. This paper presents an investigation on the cause and rectification of weight loss in delicatessen cabinets. Specifically, the paper describes the effective use of low emissivity glass in reducing the impact of the thermal infrared radiation on the food temperatures and energy consumption.
This paper presents a feasibility study of the technical and economic viability of introducing co... more This paper presents a feasibility study of the technical and economic viability of introducing combined heating and cooling networks, referred to collectively in this paper as “thermal networks”. The steps used for this study include the identification of the most viable thermal network configuration, followed by analysis of a number of potential building mix scenarios and estimation of their respective potential impact on energy consumption, carbon emissions and economics. The final step was a discussion of the potential benefits and drawbacks associated with the implementation of the selected thermal network. This study revealed that by utilising thermal networks, with central energy centres, approximately 1831 tonnes of CO2 could be saved per annum compared to traditional supply methods. With a minimum assumed system life of 25 years this equates to approximately 46000 tonnes CO2. It has also been identified that, in conjunction with a marginal shift in policy to encourage an inc...
This paper presents the results of a study carried out at London South Bank University into how c... more This paper presents the results of a study carried out at London South Bank University into how current electrical power generation and storage technologies might be integrated with advanced energy management systems to achieve zero carbon dwellings to 2016 (implementation of the Code for Sustainable Homes (CSH) Level-6) and beyond. Whereas thermal energy demands of buildings are tending to decrease as they become more thermally efficient, electrical energy demands for dwellings are unlikely to decrease significantly, because the increasing efficiency of electrical equipment and appliances tends to be offset by higher levels of ownership and utilization. Baseline energy demand profiles were developed for a range of typical dwellings built to Part L 2006 building standards [1] and then used to predict the energy demand for similar dwellings if built in 2016 to CSH Level-6 [2,3]. A renewable electrical power generation and storage model was developed and used with the electrical energ...
“Modelling and Performance Evaluation of a Low Temperature Ammonia-Water Absorption Refrigeration... more “Modelling and Performance Evaluation of a Low Temperature Ammonia-Water Absorption Refrigeration System”, Energy Conversion and Management, 2008.
Food retail supermarkets consume significant amounts of energy with large supermarkets accounting... more Food retail supermarkets consume significant amounts of energy with large supermarkets accounting for up to 5% of the total energy consumption in developed countries. A major opportunity to reduce energy consumption in this sector is to employ local Combined Heat and Power (CHP) generation systems. However, the lower heat demand of supermarkets has hindered the full utilisation of localized CHP generation systems in this sector. A way of overcoming this is to convert the heat energy from the CHP unit into another form that is continuously required by the supermarkets instead of dumping it. This could be done by integrating the CHP unit with low temperature heat driven absorption chillers forming a trigeneration system that will provide electrical power, heating and refrigeration to the supermarket throughout the year. This paper presents an assessment of tri-generation technology for use in a 30,000 ft 2 food retail supermarkets, based on 80 kWe modular micro gas turbine (MGT) CHP p...
Environmental footprinting is widely used in the academic, industrial and political circles alike... more Environmental footprinting is widely used in the academic, industrial and political circles alike. But it is in the product centric category of environmental footprinting techniques that Product Carbon Footprint (PCF) and Life Cycle Assessment (LCA) emerged as pivotal instruments in response to the climate change and sustainability imperatives. In addition, these techniques have been the object of several international assessment guidelines and according to Carbonostics (2011) and Fishwick (2012) they can be evaluated in terms of international acceptance, time/cost involvement and comparability. In contrast, little literature discusses the dissimilarities inherent in the use of different environmental measurements for an identical product. That is the reason why this paper presents a comparison between the results obtained from a Product Carbon Footprint (PCF) against that of Life Cycle Assessment (LCA) for an identical Refrigerated Display Cabinets (RDC). Results of the study show ...
The Centre for Efficient and Renewable Energy in Buildings (CEREB) is a unique, teaching, researc... more The Centre for Efficient and Renewable Energy in Buildings (CEREB) is a unique, teaching, research and demonstration resource for the built environment. It is located at London South Bank University (LSBU) and showcases different renewable and low carbon energy solutions for which performance data is captured for teaching and research. The technologies included are Ground Source Heat Pump (GSHP) for providing heating and cooling to the 8,500 m 2 K2 building which is located below CEREB. The solar thermal collectors are used to provide the hot water demand of the K2 building, with back-up boilers to supplement the required heat on cloudy days. The centre itself has additional technologies including solar fibre optic lighting, solar Photovoltaic (PV) panels, solar thermal tubes (evacuated tubes), phase change materials, absorption chiller for cooling, and a weather station, which is crucial for researching the technologies. This paper consists of two parts; the first part presents a b...
The discharge temperature of CO 2 transcritical system can provide high grade heat that can be re... more The discharge temperature of CO 2 transcritical system can provide high grade heat that can be reclaim and re-use for hot water services, space heating and cooling systems. This paper investigates the performance of an innovative booster R-744 system with heat recovery at different operating conditions based on its mathematical EES model which includes the variation of the cooling capacities of different size of stores, discharge pressures, receiver pressure and superheats.
This presentation describes the work undertaken by the IIR Working Party and the results achieved... more This presentation describes the work undertaken by the IIR Working Party and the results achieved, including the information on refrigerant leakage and containment that has been collected, collated, and categorized. The availability of such information on the IIR’s FRIDOC database and gaps in current knowledge are also discussed. A new IIR Informatory Note on refrigerant emissions is presented.
Global warming and the urban heat island effect in large towns and cities demand new approaches t... more Global warming and the urban heat island effect in large towns and cities demand new approaches to cooling buildings in an efficient and sustainable way. Modern refrigeration, air conditioning and heat pump (RACHP) systems can achieve a high coefficient of performance and low direct emissions (through reduced refrigerant leakage and the use of low global warming potential alternatives), but refrigeration technology already accounts for around 15% of worldwide electricity use and up to 10% of all greenhouse gas emissions, so in the context of international agreements to reduce global greenhouse gas emissions by up to 80%, RACHP systems alone cannot provide a sustainable cooling solution for cities. The purpose of the model described in this paper is to provide a simple and easy to use tool to estimate the impact of different RACHP technologies, alternative building design and operating parameters and future global warming, on the energy demands and carbon emissions of buildings. This...
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