Rebound effect (conservation)

About: Rebound effect (conservation) is a research topic. Over the lifetime, 773 publications have been published within this topic receiving 25741 citations.

Heat pumps and user practices – energy reductions or increased comfort?

Abstract: This paper deals with individual air-to-air heat pumps in dwellings and summerhouses and the question of to what extent they deliver actual savings in energy consumption . Results show that 40% of the expected reduction in electricity consumption is transferred into increased comfort in the homes, including increased heating areas, keeping a higher temperature and a longer heating season and using the heat pump for air-conditioning. Data include electricity consumption in 185 households before and after installation of heat pumps together with survey results of 480 households. Furthermore 12 households are selected for in-depth analysis including technical inspection and qualitative interviewing. Especially for summerhouses results indicate that there on average is no reduction in electricity consumption, as energy efficiency is outbalanced by increased comfort. These results have to be taken into account when making long term energy planning for a sustainable energy system. INTRODUCTION The sale of air-to air heat pumps has been quite high, notably in Norway where there are sold some hundred thousand [1] but also in Sweden and France expanding sales figures of heat pumps are reported. In Sweden domestic heat pump sale rose from approximately 20000 to 80000 per year between 2006 and 2007 and in France from approximately 50000 to 70000 per year [2]. Studies from several different European countries has pointed out that there is good economical reason for the consumers to install air-to-air heat pumps [3, 4, 5]. The question of what role air-to-air heat pumps play in a future sustainable energy system have to be discussed together with other technical changes of the whole energy system including to what extent electricity is produced by renewable energy [6,7] and the energy renovation of the building stock [6]. Replacing direct electric heating with air-to-air heat pumps are, however, always more energy efficient because heat pumps can provide 2-5 times more heat than the electricity they use as driving force [3]. In a scenario for future 100% renewable energy systems in Denmark * Corresponding author * The project team included besides the authors also Troels Fjorbak Larsen, IT Energy; Erik Gudbjerg and Lisbeth Rasmussen, Lokalenergi and Preben Munter, Seas-nve. † The initial project was financed by Elforsk.dk and further analysis for this article was related to the Research Centre for Zero Energy Buildings (http://www.zeb.aau.dk). individual heat pumps are thus also included for areas not covered by district heating [9]. From a socio-technical point of view it can, however, be expected that the full technical potential for energy efficiency will not be met because of changes in user practices towards still higher expectations and norms of comfort [1] as is also known from studies of other types of households’ technologies [10]. Within a techno-economic perspective a corresponding phenomenon is known as the rebound effect focusing on how the economic gains that households get from implementing more efficient technologies will be used to increase consumption in other areas or within the same area resulting in higher standards and thus increased energy consumption. There has been a debate about the size of the rebound effect within the household sector and a recent review suggest a rebound effect on 20% meaning that 20% of the energy savings gained from efficient technologies within the household sector are transformed into increased energy consumption and thus not realised as energy savings [11, 12]. The purpose of the study presented in this paper was to analyse to what extent the potential reduction from installation of air-to-air heat pumps are realised or transformed into increased consumption. Furthermore, it was to go more into detail in explaining within which areas more precisely the increases in comfort is seen and to understand in more sociological terms why and how these changes occur. Today, 8% of houses in Denmark [13] and 84% of summerhouses are heated by direct electric heating [14]. The majority of these are not placed near city centres and thus reachable by district heating and the most relevant future heating supply for these homes is thus individual heat pumps [9]. As these houses have not installed central heating based on water-borne systems, the economically most attractive choice will most often be to install air-to-air heat pumps. Another argument for looking at air-to-air heat pumps in relation to changes in comfort norms is that these can easily be used for air-conditioning as well. Air-conditioning has until now not been normal in Danish households, however, having available technologies installed in the home might contribute to change this. In the following, we will first describe the methods of the study and then, in the main part of the paper, present findings and analysis for permanently occupied dwellings and summerhouse respectively. In the conclusion, results are discussed in relation to the implications for interaction between heating technologies and renewable energy systems.

Are Chinese transport policies effective? A new perspective from direct pollution rebound effect, and empirical evidence from road transport sector

Abstract: The air pollution has become a serious challenge in China. Emissions from motor vehicles have been found as one main source of air pollution. Although the Chinese government has taken numerous policies to mitigate the harmful emissions from road transport sector, it is still uncertain for both policy makers and researchers to know to what extent the policies are effective in the short and long terms. Inspired by the concept and empirical results from current literature on energy rebound effect (ERE), we first propose a new concept of pollution rebound effect (PRE). Then, we estimate direct air PRE as a measure for the effectiveness of the policies of reducing air pollution from transport sector based on time-series data from the period 1986-2014. We find that the short-term direct air PRE is -1.4105, and the corresponding long-run PRE is -1.246. The negative results indicate that the direct air PRE does not exist in road passenger transport sector in China, either in the short term or in the long term during the period 1986-2014. This implies that the Chinese transport policies are effective in terms of harmful emissions reduction in the transport sector. This research, to the best of our knowledge, is the first attempt to quantify the effectiveness of the transport policies in the transitional China.

Intelligent Dynamic Pricing Scheme for Demand Response in Brazil Considering the Integration of Renewable Energy Sources

Abstract: This paper proposes a novel dynamic pricing scheme for demand response with individualized tariffs by consumption profile, aiming to benefit both customers and utility. The proposed method is based on the genetic algorithm, and a novel operator called mutagenic agent is proposed to improve algorithm performance. The demand response model is set by using price elasticity theory, and simulations are conducted based on elasticity, demand, and photovoltaic generation data from Brazil. Results are evaluated considering the integration effects of renewable energy sources and compared with other two pricing strategies currently adopted by Brazilian utilities: flat tariff and time-of-use tariff. Simulation results show the proposed dynamic tariff brings benefits to both utilities and consumers. It reduces the peak load and average cost of electricity and increases utility profit and load factor without the undesirable rebound effect.

Heterogeneity in the rebound effect: Further evidence for Germany

Abstract: Rebound effects measure the behaviorally induced offset in the reduction of energy consumption following efficiency improvements. Using both panel estimation and quantile regression methods on household travel diary data collected in Germany between 1997 and 2009, this study investigates the heterogeneity of the rebound effect in private transport. With the average rebound effect being in the range of 57% to 62%, our results are in line with a recent German study by Frondel, Peters, and Vance (2008), but are substantially larger than those obtained from other studies. Furthermore, our quantile regression results indicate that the magnitude of estimated fuel price elasticities – from which rebound effects can be derived – depends inversely on the household's driving intensity: households with low vehicle mileage exhibit fuel price elasticities, and hence rebound effects, that are significantly larger than those for households with high vehicle mileage.