SPRU - Science Policy Research Unit

Rebound Effects

Improved energy efficiency is critical for the development of sustainable energy systems. But does energy efficiency lead to a net reduction in energy consumed?

graphic energy policyNot only does energy efficiency offer the largest technical potential for reducing carbon emissions, it can also be highly cost effective and avoid the negative environmental impacts of many supply-side options. But improved energy efficiency can have multiple unintended consequences that have the potential to erode much of the anticipated energy savings. For example, buying a fuel–efficient car but driving more often because it is cheap to run, or using the money saved in running a more efficient car to go on a transatlantic holiday. Analysts and policymakers tend to ignore these so-called ‘rebound effects’, but research at SPRU, led by Dr Steve Sorrell has shown they could be highly significant.

Dr Steven Sorrell has been working on rebound effects for a number of years and, together with colleagues, has produced eight journal articles, an edited book, seven book chapters, a widely cited synthesis report, five comprehensive technical reports, two conference papers and numerous presentations at conferences and workshops in the UK and overseas.

Methodology

Steve’s original work on rebound effects was funded by the UK Energy Research Centre. The project applied the methodological techniques of systematic reviews to: identify the nature, operation and magnitude of different types of rebound effect; clarify the relevant theoretical and methodological concepts, assess the strengths and weaknesses of the available evidence base, identify research and data gaps and highlight the implications for energy and climate policy. The result was the most thorough and in-depth review of rebound effects ever undertaken, reviewing over 500 papers and reports and supported by original research. 

Findings

The study concluded that the neglect of rebound effects can no longer be justified and that the contribution of energy efficiency policies to emissions reductions needs to be significantly reappraised. While ‘direct’ rebound effects for energy efficiency improvements by OECD households appear to be relatively modest, this forms only a small part of the broader picture. A growing body of evidence suggests that economy wide rebound effects are frequently large (e.g. greater than 50%), especially following energy efficiency improvements by producers and over the longer term. In many important cases, energy efficiency improvements are likely to increase aggregate energy consumption and carbon emissions.

Impact and Influence

The study attracted widespread media attention, including BBC Radio 4 (Today Programme), BBC Radio 5, BBC World Service, BFBS Radio, four UK national newspapers (Mail, Telegraph, Guardian, Independent), Forbes, several BBC local radio stations (Northampton, York, Northern Ireland, Three Counties), the Economist magazine and a large number of websites and trade publications. Media interest in this topic has continued, leading to subsequent interviews and coverage in Guardian Online (June 3: 2011), New York Times (March 7, 2011), New Yorker (2010), Conservation (2011) and Scientific American (2012) amongst others.

The research led to a follow-up project (Mapping rebound effects for sustainable behaviours) funded by DEFRA, together with advisory work on policy relevant research projects undertaken by the US Clean Air Task Force, the European Commission (Addressing the rebound effect), the Centre for European Economic Research (the Rebound Effect: an empirical analysis for Germany) and the International Risk Governance Council. The synthesis report for the project formed the foundation for a publication by the US Breakthrough Institute which attracted significant media attention in the US. Both the European Commission and the Breakthrough projects document a significant increase in the number of academic publications and other reports on the rebound effect, following the publication of the UKERC study. 

The study led to several meetings with UK policymakers and the results have informed policy guidance from the UK Department Energy and Climate Change (Valuation of energy use in greenhouse gas emissions for appraisal and evaluation, 2010) and the UK Parliamentary Office of Science and Technology (POST Note 49).

Dr Sorrell’s work on rebound is also repeatedly cited in the latest report from Working Group 3 of the Intergovernmental Panel on Climate Change (IPCC) and reflects the massive increase in research on rebound effects since 2007 – triggered in part by the UKERC study. This review, together with Steve’s subsequent work on rebound effects, receives repeated citations within the IPCC Fifth Assessment Report and has clearly helped shape several of the conclusions. The Technical Summary of the Working Group III report devotes an entire section to this topic (p91), with further sections in Chapter 5 (p54), Chapter 8 (p 23), Chapter 9 (p 46-47) and elsewhere.

A follow up project ‘Rebound effects in UK transport’ is currently in progress as part of the Centre on Innovation and Energy Demand, one of six research centres on end use energy demand funded by the UK Research Councils. CIED is directed by Dr Steve Sorrell.

Contact

Dr Steven Sorrell: s.r.sorrell@sussex.ac.uk

This project sits within the Sussex Energy Group at SPRU