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Abstract: Demand-side management (DSM) refers to actions undertaken on the demand side of energy metres. A broad definition of DSM is proposed to include current policy objectives for emissions reduction, energy security and affordability, and encompasses energy efficiency, demand response, and on-site back-up generation and storage. The paper reviews the concept of DSM, outlines the historical impacts of DSM globally since the energy crises of the 1970s, analyses UK DSM policy, and examines the influence of EU Directives on UK DSM policy, as the country is currently deciding on how to include the demand-side in its Electricity Market Reform proposals and wider energy policy. Much of the focus of previous research has been on DSM technological trials and modelling studies rather than DSM policy and the paper contributes to filling this gap. Policy recommendations for the UK context are discussed, and it is clear that the success of DSM policies is determined primarily by regulatory support and utility financial incentives. It is important that policy clarity is provided and that current and new policies do not overlap. [Copyright &y& Elsevier]

Abstract: Thermal energy loss in the process industry is a significant issue due to the high temperatures and multiple heat intensive processes involved. High-grade thermal energy is typically recovered within processes. However, lower grade heat is often rejected to the environment. The benefits of capturing and utilising low grade thermal energy are highly dependent on the qualities and properties of the heat in the waste streams. The temperature of the low grade heat stream is the most important parameter, as the effective use of the residual heat or the efficiency of energy recovery from the low grade heat sources will mainly depend on the temperature difference between the source and a suitable sink, e.g. another process or space heating/cooling. In general, the temperatures of these waste heat sources are too low to produce electricity and direct heat use will depend on whether potential user can be found. This paper presents past and current drivers for heat recovery studies. High and low grade heat sources are defined according to the viability of recovery within the processes. Firstly, high grade heat capture within the processes is reviewed. Then, the focus is on the potential for low grade heat capture outside of the original plant. The paper addresses the potential for low grade heat recovery with regard to new incentives and technological advances. Finally, different aspects which influence the decision making for low grade heat recovery in the process industry are discussed. It is concluded that organisational, financial and economic barriers might be overcome and benefits from a holistic vision could be gained with stronger governmental policy and regulation incentives. [Copyright &y& Elsevier]

Currently UK industrial and manufacturing sectors are facing dual challenges of contributing to national 80% reduction targets in CO 2 emissions by 2050 (compared to 1990 levels) and improving economic competitiveness in the face of low cost imports. Since energy consumption is the main source of CO 2 emissions and directly related to products being manufactured, improving energy efficiency in energy intensive sectors is key to achieve CO 2 targets. Energy consumption is unlikely to meet the targets unless energy efficiency opportunities and technologies are fully explored and timely changes are made to business models and policies This study explores potential energy efficiency improvements from three perspectives: system efficiency of steam networks, waste heat recovery technologies and bioenergy/waste utilisation. Two UK energy-intensive sectors, iron and steel, and food and drink, are selected for analysis and discussion. Potential business models for energy efficiency are also reviewed as there are now a variety of energy service companies who can support adoption of appropriate technologies. Furthermore, drivers and barriers to the adoption of energy efficiency technologies are considered in this paper revealing the factors affecting the diffusion of energy efficient and waste heat recovery technologies and their interactions and interdependencies to energy consumptions. Findings show that it is possible to achieve energy consumption reduction in excess of 15% from a technical point of view, however improving energy efficiency in UK industry has been hindered due to some inter-related technical, economic, regulatory and social barriers. The findings help to demonstrate the significant potential for energy efficiency improvement in two industrial sectors, as well as showing the specific types of technologies relevant for different sectoral processes. The range of business models show opportunities for implementation and for developing innovative business models, addressing barriers, and using enablers to accelerate the diffusion of energy efficiency technologies in UK industry. [ABSTRACT FROM AUTHOR]

Abstract: Fossil fuel energy use in heating and cooling buildings is considered to be a major contributor to observed climate change effects, so there is an environmental imperative to reduce energy use in buildings. We should also improve buildings’ energy efficiency on health grounds. Climate change is predicted to produce more frequent extreme weather events, while epidemiological evidence indicates relationships between ambient temperature and ill health. This points to the need for addressing both climate change itself and the way buildings mediate outdoor conditions, for the sake of vulnerable occupants. The UK government requires evidence in support of policy-making concerning energy use in buildings and consequences for health. This paper reviews epidemiological research to illustrate problems associated with measuring the direct health impact of indoor temperatures, for which evidence remains limited. Conventionally, temperature-related health effects are discussed in terms of seasonal excess deaths. The paper goes on to describe a population-based study in London that considers morbidity rather than mortality. A new methodology is developed that links the risk of cold homes with excess winter hospital episodes, demonstrating its potential for identifying small areas for priority action on improving domestic energy efficiency in terms of health as well as the environment. [Copyright &y& Elsevier]

Understanding homeowners' renovation decisions is essential for policy and business activity to improve the efficiency of owner-occupied housing stock. This paper develops, validates and applies a novel modelling framework for explaining renovation decisions, with an emphasis on energy-efficiency measures. The framework is tested using quantitative data from a nationally-representative survey of owner-occupied households in the UK (n = 1028). The modelling advances formal representations of renovation decisions by including background conditions of domestic life to which renovating is an adaptive response. Path analysis confirms that three conditions of domestic life are particularly influential on renovation decisions: balancing competing commitments for how space at home is used; signalling identity through homemaking activities; and managing physical vulnerabilities of household members. These conditions of domestic life also capture the influence of property characteristics (age, type) and household characteristics (size, composition, length of tenure) on renovation decisions but with greater descriptive realism. Multivariate probit models are used to provide rigorous, transparent and analytically tractable representations of the full renovation decision process. Model fits to the representative national sample of UK homeowners are good. The modelling shows that renovation intentions emerge initially from certain conditions of domestic life at which point energy efficiency is not a distinctive type of renovation. The modelling also shows clearly that influences on renovation decisions change through the decision process. This has important implications for policy and service providers. Efficiency measures should be bundled into broader types of home improvements, and incentives should target the underlying reasons why homeowners decide to renovate in the first place. [ABSTRACT FROM AUTHOR]

This paper presents the methodological approach and findings of a simulation study of advanced energy conservation, generation and management technologies applied to two case study dwellings in the UK, so as to achieve net zero energy (NZE) target that includes a reduction of net regulated energy (HVAC) to 0 kWh/m 2 per year and energy generation of at least 50 kWh/m 2 per year. The performance of the dwellings are also tested for a change in energy use and risk of summertime overheating in future climates in the short (2030s), medium (2050s) and long term (2080s). The findings indicate that to meet the NZE targets, regulated loads need to reduce by about half (over current Building Regulations) with community (rather than building-level) renewables playing a major role. It is also found that the NZE targets, given current regulations, are not particularly difficult to achieve in design with regard to energy efficiency but are highly expectant with regard to renewable energy. Further, summertime overheating is projected to be a risk for net zero energy dwellings by the 2050s. Despite this the regulated energy use of both dwellings is projected to reduce by 11 kWh/m 2 /yr, accompanied by a small increase in renewable generation (2 kWh/m 2 /yr). [ABSTRACT FROM AUTHOR]

In the UK, 20% of houses were built before 1919 and are protected from energy efficiency requirements that would unacceptably alter their character. To meet carbon emission reduction targets, however, it is necessary to keep the number of buildings exempt from energy efficiency improvements to a minimum. The need to preserve the aesthetic and structural qualities of historic buildings makes energy retrofit complicated and costly but these arguments should not be used to resist change. The research presented in this paper investigates how conservation professionals in the UK approach and sanction energy retrofit measures in historic buildings. It provides an overview of the current UK legislation and guidance relating to energy efficiency in heritage buildings and presents findings from a study focused on the approach of conservation professionals to retrofit slim profile double glazing (SPDG). It finds that there is regional variation to energy retrofit in historic buildings between Scotland and the rest of the UK, and that individual conservation professionals hold different views on the use of SPDG, which leads to inconsistencies in its application. Recommendations are made for a more consistent approach to window upgrade as a means of improving the energy efficiency and comfort of historic buildings and for greater interdisciplinary cooperation to align conservation of energy with conservation of heritage. [ABSTRACT FROM AUTHOR]

Energy efficiency has become a primary energy policy goal in Europe and many countries and has conditioned the policies towards energy-intensive sectors such as road freight transport. However, energy efficiency improvements can lead to changes in the demand for energy services that offset some of the achieved energy savings in the form of rebound effects. Consequently, forecasts of energy savings can be overstated. This paper analyses the energy efficiency and rebound effects for road freight transport in 15 European countries during the 1992–2012 period. We use a recent methodology to estimate an energy demand function using a stochastic frontier analysis approach and examine the influence of key features of rebound effect in the road freight transport sector. We obtain, on average, a fuel efficiency of 89% and a rebound effect of 4%. Our results indicate that the achieved energy efficiencies are retained to a large extent. We also find, among other results, that the rebound effect is higher in countries with higher fuel efficiency and better quality of logistics. Finally, a simulation analysis shows significant environmental externalities costs even in countries with lower rebound effect. [ABSTRACT FROM AUTHOR]

The dependence of cities on intensive consumption of energy from fossil fuels is a major cause of climate disruption, and there is increasing interest in the potential for city governments to facilitate a transition to sustainable energy. Little is known, however, about the extent or structures of current urban energy initiatives. Our paper addresses this gap by mapping UK local authority energy plans and project investments and exploring governance processes in three leading cities. It uses socio-technical and urban studies' perspectives on neo-liberal governing and energy systems to interpret findings. This reveals both the gap between local ambitions and capacity to implement plans, and the potential for translation of neo-liberal governing into contrasting commercial and community urban energy enterprises, prefiguring different energy futures. Overall, however, the neo-liberal framework is associated with small scale and uneven initiatives, with limited contribution to a systemic shift to sustainable cities. [ABSTRACT FROM AUTHOR]

Improved methods for quantifying energy savings in buildings need to be supported by empirical measures rather than modeled estimates of future annual energy demand. This paper uses power temperature gradient (PTG, W/K), or the slope of power demand in response to changes in external air temperature; first, to categorise dwelling energy performance from daily energy data (when 0–15 °C outside); second, to investigate variations in 24-h profiles of delivered power. Estimates of PTG were obtained from 567 UK dwellings with 118,000 days of gas and electricity data. From a multivariable regression model, PTG was predicted by dwelling characteristics (number of bedrooms, number of floors, dwelling type, and dwelling age category (all p < 0.001)) but not by number of occupants. When dwellings were grouped into quintiles of PTG, mean PTG had threefold increase from the first to fifth quintile (188 to 563 W/K, respectively). This was reflected in 24-h profiles of delivered power (30 min intervals): at 0 °C, each 100 W/K decline in PTG corresponded to ∼2.5 kW decline in mean morning and evening peak power. Using PTG to estimate reductions in peak power as equivalent ‘negawatts’ reframes potential benefits of energy efficiency retrofits and for grid resilience. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the economic impact of a 5% improvement in the UK household energy efficiency, focussing specifically on total energy rebound effects. The impact is measured through simulations using models that have increasing degrees of endogeneity but are calibrated on a common data set, moving from a basic partial equilibrium approach to a fully specified general equilibrium treatment. The size of the rebound effect is shown to depend on changes in household income, aggregate economic activity and relative prices that can only be captured through a general equilibrium model. [Copyright &y& Elsevier]

Abstract: The work forms part of the CALEBRE project (2008–2013), the aim of which was to investigate a suite of technologies and staged approaches for retrofit upgrades for ‘hard-to-treat’ solid/thin cavity masonry-walled UK domestic buildings that would i) reduce operational energy demand/carbon emissions, and ii) be acceptable and appealing to the building occupants. The E.ON Retrofit Research House (Nottingham, UK) was used as an instrumented test platform as part of this study. The retrofitting phases (and technologies) have been used as the basis for the modelling methodology in this paper, together with the corresponding envelope assemblies, material properties, climate, and internal load parameters. The approach to retrofit was to increase air tightness (reduce ACH), decrease static U-values of the external envelope (wall, floor and glazing), and upgrade heating system efficiency. This was complemented by a combination of options that included a whole-building system of mechanical ventilation with heat recovery (MVHR). These interventions were analysed alongside simulated passive buffering of variations in indoor air psychrometric conditions using conventional (clay, timber) and advanced (mesoporous silica) wall surface treatments. Each retrofit scenario was modelled using an energetic hygrothermics building performance simulation (BPS) approach to determine the combined effects of retrofit packages on indoor air psychrometric conditions, external envelope (dynamic) heat transfer, operational energy efficiency, occupant comfort, and mould growth potential. It is proposed that this approach can provide the basis for an intelligent risk management strategy to inform both the design and deployment of retrofit upgrade packages intended for residential buildings. [Copyright &y& Elsevier]

Abstract: Despite increasingly stringent building energy regulations worldwide, non-compliance exists in practice. This paper examines the profile of compliance with building energy regulations for new-build dwellings. In total 404 new-build dwellings completed in the UK from 2006 to 2009 were investigated. Only a third of these dwellings were evidenced as being compliant with Building Regulations Part L (England and Wales). Such low compliance casts a serious concern over the achievability of the UK Government''s target for all new-build homes to be ‘zero carbon’ from 2016. Clearly evidenced was a lack of knowledge of Part L and its compliance requirements among the supply and building control sides of new-build dwellings. The results also indicate that the compliance profile was influenced by factors including Standard Assessment Procedure (UK Government''s methodology for energy efficiency) calculation submissions, learning and experience of builders and building controls with Part L, use of Part L1A checklist, the introduction of energy performance certificate (EPC), build method, dwelling type, and project size. Better compliance was associated with flats over houses and timber frame over masonry. The use of EPC and Part L1A checklist should be encouraged. Key to addressing the lack of compliance with building energy regulations is training. [Copyright &y& Elsevier]

Abstract: This paper presents a study which linked demographic variables with barriers affecting the adoption of domestic energy efficiency measures in large UK cities. The aim was to better understand the ‘Energy Efficiency Gap’ and improve the effectiveness of future energy efficiency initiatives. The data for this study was collected from 198 general population interviews (1.5–10 min) carried out across multiple locations in Manchester and Cardiff. The demographic variables were statistically linked to the identified barriers using a modified chi-square test of association (first order Rao–Scott corrected to compensate for multiple response data), and the effect size was estimated with an odds-ratio test. The results revealed that strong associations exist between demographics and barriers, specifically for the following variables: sex; marital status; education level; type of dwelling; number of occupants in household; residence (rent/own); and location (Manchester/Cardiff). The results and recommendations were aimed at city policy makers, local councils, and members of the construction/retrofit industry who are all working to improve the energy efficiency of the domestic built environment. [Copyright &y& Elsevier]

Recently, retrofit of tower blocks has gained momentum particularly in the UK social housing sector due to the increasing rate of fuel poverty coupled with deteriorating indoor living conditions. However, the process of making improvements to the thermal performance of building envelopes can significantly impact on occupants' thermal comfort, increasing overheating risks with the changing climate and associated heat waves. The first phase of the study evaluated the building energy performance of a 1960s social housing tower block prototype in London, pre-retrofit, where the building simulation model was created and calibrated with monitored indoor data and occupants' interviews. The second research phase, the subject of this paper, uses the model to further investigate the impact of improved thermal insulation of the building envelope, based on U-values prescribed by the UK Building Regulations (Part L1B), on the potential risk of overheating. The study investigates the impact of retrofitting on occupants' thermal comfort and building energy performance in the current and future climate scenarios (2030, 2050 and 2080). Results confirm that improving the U-value of external walls will significantly reduce the heating energy use by 70% under future climate scenarios while the T o increases by 15–17% with U-value of 0.5 W/m2K and 0.3 W/m2K in comparison to the base case. The overall results indicate that the different occupancy patterns adopted in the simulation model have a significant impact on the predicted duration of overheating which will, in turn, have an impact on determining appropriate retrofit strategies to reduce overheating risks. • The overheating risk is not sufficiently addressed in the UK Building Regulations Approved Documents. • The study demonstrates the importance of real occupancy patterns in predicting overheating risks and heating energy demand. • Retrofitting 1960s tower blocks will have major impact on occupants' thermal comfort and building energy performance. • Improving the U-value of external walls significantly reduce the heating energy use by 70% under future climate scenarios. • Operative temperature increases by 15-17% with U-value of 0.5 and 0.3 W/m2K in comparison to the base case (0.9 W/m2K). [ABSTRACT FROM AUTHOR]

District heating schemes can act as enablers for the use of low carbon heat sources. Heat rejected by industrial sites could potentially be used in supplying such schemes but various constraints limit the extent to which this is likely to occur. This study estimates the quantity of heat that could be supplied to district heating networks from industrial sites in Great Britain (GB), in the context of a range of limiting criteria. An existing spatially disaggregated database of GB's heat demands was combined with previous analysis of the magnitude, temperature and location of the heat that is rejected by industrial sites. The heat that could be supplied from the industrial sites to the heat demands was then calculated with a range of different criteria applied. The criteria which were considered included the maximum allowable distance between the heat sources and demands, the minimum heat density of the demands which was considered feasible, the heat losses that may occur, and the seasonal profile of the heat demands. The potential gains from using absorption heat pumps, driven by high temperature heat to supply lower grade heat were found to be limited. High and low estimates of the heat rejected by the industrial sites were compared. Domestic and non-domestic heat demands were examined. Although the domestic demands have a greater total, they tend to occur at lower densities and so it is likely that both demands will take a significant share of the heat supplied. The seasonality of the heat demands has a greater impact on the need for supplementary heat sources than on the total heat delivered. For the distance and heat demand density criteria considered most appropriate, only half of the heat which is rejected by industry could be utilised by district heating networks. [ABSTRACT FROM AUTHOR]