Solar assisted heat pumps

Solar Assisted Heat Pumps have the potential to provide low carbon heat for domestic hot water generation and low temperature heating. They have advantages over conventional solar thermal systems because they can generate heating and hot water during periods of low or zero solar, whist still maintain the advantage of not needing to be connected to the gas grid. They are simple in nature and can be installed in a wide range of applications. They are also currently uncommon in the UK so a thorough understanding of the operating performance and characteristics is required. This is potentially an important energy technology that can be used to reduce heating energy consumption and reduce CO2 equivalent emissions in buildings. The paper describes the technology and presents an investigation in an office application. It describes an experimental investigation of solar assisted heat pumps which gives the relative performance compared to conventional methods

Investigation of an integrated low carbon solar assisted heat pump

© 2016, International Institute of Refrigeration. All rights reserved.Solar Assisted Heat Pumps have the potential to provide low carbon heat for domestic hot water generation and low temperature heating. They have advantages over conventional solar thermal systems because they can generate heating and hot water during periods of low or zero solar, whist still maintain the advantage of not needing to be connected to the gas grid. They are simple in nature and can be installed in a wide range of applications. They are also currently uncommon in the UK so a thorough understanding of the operating performance and characteristics is required. This is potentially an important energy technology that can be used to reduce heating energy consumption and reduce CO2 equivalent emissions in buildings. The paper describes the technology and presents an investigation in an office application. It describes an experimental investigation of solar assisted heat pumps which gives the relative performance compared to conventional methods

Economical comparison of CHP systems for industrial user with large steam demand

In this paper cogeneration benefits applied to a user with a high steam demand are analyzed. The methodology for the feasibility study and the economical analysis of the investment is presented under the Italian legislative framework. The methodology is applied to an actual case and a detailed description and discussion of all data input is provided. Especially this last key point will be faced using starting data usually available in these kind of studies (i.e., not very detailed for thermal consumption). Finally a comparison of different CHP technologies and a sensitivity analysis is done

Project SHOES: Secondary heat opportunities from electrical substations

Through the mechanism of stepping up and stepping down voltages with electrical power transformers, losses in the form of heat occur and are dissipated to the atmosphere. These losses have the opportunity to be recovered and upgraded to help support the thermal demands of buildings as allow carbon secondary heat source. The electrification of heat facilitates the uptake of electrically driven heat pumps that are efficient means of upgrading low temperature heat sources to commonly used temperatures and the employment of district heating networks enables the transition of these alternative heat sources into the economy. This paper describes the results discovered from an initial investigation on the contribution available from a transformer energy recovery scheme using the Southampton Bulk Supply Point substation and District Heating Scheme as a case study. Benefits to the heat sector and asset owner are analysed from the results considering the techno-economic, environmental and social performance with the aim to provide guidance to the engineering community for further in-depth feasibility studies on this waste energy recovery concep

The Impact of Policy Changes: The Opportunities of Community Renewable Energy Projects in the UK and the Barriers they Face

The UK’s energy system is predominantly centralised with a major reliance on fossil fuels. The trilemma of successfully delivering energy security, equity, and environmental sustainability, whilst dealing with an ageing energy infrastructure, demands change within the entire energy system. In recent years, Community Renewable Energy (CRE) projects have played a significant role in the transition of the UK’s energy system, but since 2016 government support for them has been less robust. This paper reports a web-based survey and semi-structured interviews of the UK’s community energy groups undertaken between August 2016 and March 2017. The results indicate that huge problems have arisen due to the changes in government policy, particularly for solar photovoltaic schemes. The majority of CRE organisations have chosen to focus on managing their existing assets rather than plan further growth. Additionally, this paper highlights the key challenges facing CRE projects that wish to develop innovative business models under the new policy conditions. Keywords: Community Renewable Energy (CRE); Business model; Feed -in-Tariff (FIT

Simulation of the heat recovery use of R744 systems in a supermarket

This paper describes the outcomes a research project that investigate the improvement in the COP of an enhanced booster R744 refrigeration system that provided MT cooling for chilled food cabinets and LT cooling for cold room/frozen food cabinets by recovering the heat rejected and using it more for other building services applications in the supermarket. For instance, the heat reclaimed can be used for heating, HWS or to drive absorption chillers, either in whole or in part. To demonstrate the potential of the heat reclaimed within the supermarket and its impact on the store’s CO2e emissions, a feasibility study has been performed to examine the innovative system compared to of the existing conventional system which will cover the cooling demands of an existing supermarket. In order to achieve this, the data collected by a smart energy monitoring system will be used to examine the working of the novel system when covering the cooling demands of the store. The energy consumption of the novel system will be analyzed according to thermodynamic theory. Using an Excel model, the potential heat reclaimed will be mathematically investigated for best practice applications of heat recovery. The energy saved and CO2e emission reduction achieved in apply the novel system will be determined and analysed

Relationship between specific energy consumption and size of supermarket stores

© 2019 International Institute of Refrigeration. All rights reserved. Energy consumption data for 2017 were analysed for 190 retail (supermarket) stores from one retailer in the UK. The relationship between energy consumption and store size was investigated. The mean energy intensity defined by the ratio of electrical energy consumption across the sales floor area was 866 kWh.m-2.yr-1 for an average sales floor area of 469 m2. Plotting energy intensity against store size showed that smaller stores had a higher energy intensity. Measuring energy intensity using electrical energy consumption, total energy consumption, sales or gross floor area, perimeter area of the store and store volume all showed a similar trend. Electrical energy consumption is well correlated with refrigeration capacity (r2 = 0.779), however, it is has a slightly better correlation with sales floor area (r2 = 0.883). . When including these data with other data from previous studies, it can be seen that large stores (supermarkets) had an approximately constant energy intensity (decreasing slightly with increased floor area) and smaller stores (convenience) had a much higher energy intensity which increases strongly with decreasing floor area. Therefore to represent stores ranging from small to large a power law relationship is required

Body mass estimates of an exceptionally complete Stegosaurus (Ornithischia: Thyreophora): comparing volumetric and linear bivariate mass estimation methods

© 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited. The file attached is the published version of the article

Cooling with heat recovery for electrical cable tunnels in cities

Within cities, electrical power is often distributed by means of underground cable tunnels, frequently extending for many kilometres. Cables can generate significant heat, with the quantity of heat being directly related to the electrical load carried. Tunnel air temperatures are generally controlled by ventilation using outside air; preventing the cables from overheating. If active cooling was provided, tunnel air temperatures could be further reduced, permitting higher electrical loadings to be used. Using an air/water heat exchanger to cool the outside air entering the ventilation shaft has been investigated. The temperature of the heat extracted (to water) was increased using a heat pump before transfer to a heat network. Benefits identified included reduction in cable temperatures, and carbon and cost savings compared to conventional heat delivery