Ray Galvin

RWTH Aachen University & Cambridge University, UK · Economics (RWTH); Architecture (Cambridge)

Energy poverty is driven by four factors: poverty; high energy prices; energy-inefficiency; and specific household characteristics. Increasingly refined definitions of energy poverty (and/or vulnerability) identify types or locations of households most likely to be suffering it. But there is also a place for considering poverty reduction directly,...

Rebound effects have been historically studied through narrow framings which may overlook the complexity of sustainability challenges, sometimes leading to badly informed conclusions and policy recommendations. Here we present a critical literature review of rebound effects in the context of sustainability science in order to (1) map existing rebou...

Rooftop photovoltaics in Germany generate around 15 TWh of electricity per year, and there is sufficient roof area to increase this many times over. Germany’s transition to renewable electricity requires large increases in rooftop and field-based photovoltaics. However, for household systems, each kWh fed into the grid pays only €0.0653, while hous...

A popular idea for reducing CO2 emissions from existing buildings is to renovate them to “net-zero-energy” standard. In Europe this usually involves increasing the energy-efficiency of the building envelope, replacing fossil fuel boilers with heat pumps, and installing photovoltaics to generate as much energy as the building uses over the course of...

In the US a complete transition to electric vehicles (EVs) would increase demand for carbon-free electricity by around 30% if the future fleet has the same average size, weight and horsepower as current EVs. However, these dimensions for today's EVs are substantially lower than for conventional vehicles, so as EVs replace them, EV's average size, w...

Free temporary download: https://authors.elsevier.com/a/1eAHh7tZ6Ztdjm Interdisciplinary research is common in health studies and is developing in energy studies. This paper describes the process of interdisciplinary energy research in a large, three-year study of rebound effects among German households with photovoltaic panels (“prosumers”). The...

Recently diversity in transitions research has achieved increasing attention. Many diversity dimensions such as gender and geographical location, as well as their intersections, should be considered to achieve successful and just transitions. Currently, transitions research is diverse in some aspects, but the broader framework for diverse transitio...

President Joe Biden’s stated policy is to decarbonize the US light vehicle fleet by 2050 and improve on projected Obama-era standards for the years until then. The automobile as a socially constructed artifact is subject to social-cultural as well as technical constraints. The four main routes to decarbonization are reductions in horsepower, reduct...

Rebound effects after energy efficiency increases are problematic because they confound policymakers’ calculations of reductions in energy consumption and CO2 emissions. Recently rebound effect research has been extended to consider rebounds in electricity and other energy consumption, triggered by adoption of rooftop photovoltaics among households...

In the last four decades the European truck industry has made remarkable progress in energy efficiency, but this higher efficiency has failed to materialize in lower consumption per unit of load and distance (Tkm). One possible explanation is rebound effects due to average traveling speed and power enhancements. An original set of data covering for...

In the last two decades the European truck industry has made remarkable progress in energy efficiency, but this higher efficiency has failed to materialize in lower consumption per unit of load and distance (Tkm). One possible explanation is rebound effects due to average travelling speed and power enhancements. We present here an original set of d...

We develop a conceptual framework for investigating rebound effects that occur consequent to increases in renewable electricity generation and use. This is vitally important due to countries’ emerging commitments to decarbonize economies through sector-coupling and strategies such as the large-scale use of “green” hydrogen produced by electrolysis...

Generating energy by renewable sources like wind, sun or water has led to the emergence of “clean” energy that is generally available at low cost to the environment and is generated from seemingly unbounded resources. Many countries have implemented schemes to support the diffusion of renewable energies. The diffusion of micro-generation technologi...

This paper develops the social science concept of intersectionality, exploring how macro-level factors in 28 EU countries in 2010–2018 put upward pressure on the percentage of single parent households unable to heat their homes. Intersectionality research avoids categorising individuals according to one dominant characteristic, such as gender or ma...

This year a number of factors have converged to substantially increase the impetus for a credible, effective programme to radically decarbonize the economies of high-income countries, particularly in the EU but also more broadly, in ways that would reduce economic inequality and are just and sustainable. These include the European Commission’s Euro...

Rebound effects occur when energy efficiency upgrades lead to less energy saving than anticipated, compromising CO2 emission reduction. Studies of micro-level rebounds frequently emphasise human agents' personal responsibility in causing or facilitating these rebounds. Studies of macro-level rebounds tend to focus instead on autonomous, depersonali...

Prosumers are households who produce energy, usually via photovoltaic or solar-thermal panels. Studies of prosumers to date often explore the macroeconomic or psychological drivers of their household consumption patterns, or the challenges they face in optimising consumption and (for photovoltaics) feed-in to the electricity grid. But prosumers can...

Sociology has provided useful insights, especially in this journal, into energy consumption trends and practices and how their climate-damaging effects can be mitigated. But in a climate emergency a bolder and more focused sociology is required, firstly, to help us understand why humanity continues to plunge toward climate catastrophe despite heigh...

The last 3–4 decades have seen large increases in economic inequality within high-income countries. A newly emerging strand of research is exploring how this impacts on energy consumption. However, as yet there are no macro-level studies on how economic inequality relates to energy poverty on the national level. This paper investigates whether inco...

he rebound effect (RE) is an umbrella term for a range of mechanisms that undermine the expected energy savings from improved energy efficiency. Since the seminal work of Stanley Jevons (“The Coal Question”), the “problem” of the rebound effect has repeatedly appeared in energy policy debates, challenging the consensus that improved energy efficien...

Social science approaches commonly used in household energy consumption research tend to focus on regular, everyday determinants of household behavior (discourse, practices, sociotechnical relations, actor-networks, etc.). Their conceptual frames avoid consideration of economic inequality and how it affects home ownership, energy efficiency investm...

This paper reports a regional case study of key issues for Germany's energy transformation (Energiewende) in and around Schweinfurt County (Landkreis Schweinfurt) in the geographical region of Unterfranken (Lower Franconia). Document research and semi-structured interviews with strategically selected local persons were conducted, supplemented by ex...

This paper explores why domestic energy policies, thermal retrofitting and the operation of domestic energy-efficient technologies are often met with social inertia in practice. Two sets of interview data – UK homeowners who have retrofitted their property and social housing tenants living in energy-efficient housing – reveal a very different mix o...

The “rebound effect” occurs when reductions in energy consumption following energy efficiency increases are lower than engineering estimates. In cars this happens when drivers increase their distance travelled or average speed, as a behavioural response to cheaper travel. Rebound effects due to increased distance travelled have been extensively stu...

The number of electric vehicles in service throughout the world has increased from a few thousand in 2009 to some 740,000 in December 2014. These vehicles are often seen as a means of reducing climate and health damaging emissions, and their development is directly supported by some countries and endorsed by the EU. Aside from questions of rebound...

The ten questions posed in this paper stand out among others after six years of joint and collaborative research, by the authors, on sustainable domestic thermal retrofit policy. This is a very wide field, touching on many disciplines, and we approach it from an interdisciplinary perspective informed by our experience in architecture, engineering,...

I reflect on three issues in light of Adam Cooper’s paper: the logic of relationships between physical and social sciences; the place of Schatzkian practice theory (SPT) here regarding energy research; and historical contingencies that bring different research and policy challenges in different epochs. The basic subject matter of physical science i...

Rebound effect studies are useful for policy making, as they indicate the extent to which increases in energy efficiency lead to lower energy savings than those predicted by engineering calculations. Existing rebound studies assume energy consumption changes arise from an economically rational response, by consumers, to cheaper energy services. Thi...

The version of practice theory developed by Theodore Schatzki is employed increasingly in energy consumption research. This emerged in response to problems Wittgenstein had identified in the core logic of prevailing rule-based, inter-subjectivist social theories of the late 20th century. Since then, however, the use and development of Schatzkian pr...

Rebound effect studies of road vehicle travel focus mostly on increases in distance traveled after increases in energy efficiency. Average journeying speed also increases with energy efficiency, but rebound studies avoid quantifying speed-related rebound effects. This may underestimate rebound effects by around 60%. This study offers a first attemp...

In order to reduce CO2 emissions in line with UK policy, existing UK homes need to be retrofitted to high thermal standards. A large proportion of these homes have traditional or aesthetically pleasing features which people are reluctant to compromise for the sake of thermal efficiency. A minority of such dwellings are protected by statute, but mil...

The ‘prebound effect’ characterises how average heating energy consumption in older homes is consistently lower than these buildings' calculated energy ratings, and helps explain why energy savings from thermal upgrades are often lower than anticipated. This paper explores the conceptual links between prebound and rebound effects and aims to quanti...

Policymakers are increasingly concerned about rebound effects, which lead to lower savings than expected when energy-efficiency increases. There are difficulties in making coherent comparisons between magnitudes of rebound effects in different sectors, such as home heating, industry and transport. A barrier to this in domestic heating is the concep...

Policy on domestic thermal retrofits is usually designed as a top-down enterprise, setting standards and inducing homeowners to retrofit accordingly. Its underlying assumption is that correct retrofit technology is developed by experts and comes down through supply chains to households, who apply it as designed to their properties. However, this mo...

Consumption of domestic heating energy (space and water heating combined) in Germany has been falling in recent years. Official figures indicate it fell by 17 % in 2000–2011, from 669 to 564 TWh (temperature adjusted), while the population reduced by 2 % and the number of occupied dwellings increased by 3.4 %. German policy has strongly promoted de...

The ‘passive house’ (PH) is a specific, pan-nationally recognised building standard designed to consume 15 kilowatt-hours of space heating energy per square metre of living area per year (kWh/m2a), significantly less than most countries’ current standard for a conventional house (CH). Most PHs cost some 5–15% more to build than a CH of equivalent s...

One particular definition of the ‘rebound effect’ has won acceptance for its conceptual clarity and mathematical robustness: the energy efficiency elasticity of demand for energy services. This is formulated as a partial differential, and its structure enables transformations with price and energy elasticities. However, when considering heating ene...

Germany is frequently seen as a leader in thermal retrofit policy, with stringent mandatory standards for insulation, windows and boilers. However, the annual rate and average depth of thermal retrofits are considerably lower than expected. One of the main policy planks for promoting thermal upgrades is the claim that thermal retrofitting, to feder...

Concern has recently intensified regarding increases in the consumption of energy services that often follow energy efficiency improvements, a phenomenon widely called the 'rebound effect'. However, while some economists have precisely defined this as a metric, much discussion in academic and policy literature is imprecise, leading to confusion and...

A common strategy to reduce energy consumption and CO2 emissions is retrofitting residential buildings to high thermal standards. But households in retrofitted homes often consume more space heating energy than expected, thus frustrating climate and energy goals. Most interventions to mitigate this focus on energy-inefficient ‘behaviours’, and assu...

Heating energy consumption has been falling steadily in Germany since 2000. The most recent reliable figures show it fell from 669 TWh to 550 TWh in the years 2000–2009, a reduction of 119 TWh, or 18%. A number of different factors could be contributing to this: replacement of old dwellings with energy-efficient new builds; thermal retrofits of exi...

EU member states are committed to the Energy Performance of Buildings Directive (EPBD) and the Energy Efficiency Directive (EED), including a 20% energy efficiency target by 2020. Most European countries have adopted market-led policies to meet these targets, relying on voluntary take-up by homeowners. Some impose taxes on energy inefficiency, but...

Germany has engaged better-off homeowners in advanced thermal retrofits to high standards. However, at this level retrofits are inherently economically inefficient, and empirical research shows they often bring significantly smaller savings than calculated. This ‘top-end’ approach also fails to engage the bulk of homeowners, due to severe technical...

Estimates of heating fuel saving potential in German homes are generally based on a calculated consumption figure. The methodology for working this out is set down by the German Institute of Standards. But how close is this figure to dwellings’ actual heating energy consumption, and how does this affect the real energy savings potential through the...

German law restricts the thermal demands of building regulations to levels that are ‘economically viable’ (wirtschaftlich), i.e. that pay back, through fuel savings, within the technical lifetime of the thermal measures. In an effort to reduce CO2 emissions deeply and rapidly, the government sets thermal regulations as tightly as this law allows. B...

Policymakers, their expert advisors and the academic community use mathematical models to evaluate the economic viability and payback time of thermal retrofits. Most of these models have the form of a cost-benefit analysis, where the thermal upgrade costs are compared to the net present value (NPV) of the benefits expected to be received in future...

Since 2002, prescribed thermal standards have been mandatory for homes being renovated in Germany. This policy has become entwined with Germany’s climate policy of 80% reductions in GHG emissions by 2050, and is the main tool used by the Federal government to drive forward home heating energy efficiency improvements. A second policy instrument is F...

Thermal retrofitting of existing homes is widely seen as an economic and technically feasible way to reduce domestic heating energy consumption, which accounts for 14.6% of Germany’s total energy consumption. But energy savings from retrofits are dependent on the laws of physics and the geometric and physical characteristics of the actual housing s...

To make robust judgments of an energy efficiency programme's economic effectiveness, we need to know how much energy and CO2 is actually being saved through the financial support it provides. But most evaluations of home retrofit energy efficiency programmes depend on calculated, rather than measured, levels of energy consumption. This fails to tak...

Germany aims to reduce CO2 emissions by 80% by 2050 compared to 1990 levels and has merged this target with mandatory Energy Saving Regulations for thermal renovation of existing homes: the policy uses the criterion of ‘economic viability’, whereby renovations must pay back through the space and water heating fuel savings they produce. This paper e...

Manual ventilation of dwellings in winter consumes excess heating energy, as cold outdoor air replaces warm indoor air. The German government promotes ‘shock-ventilation’ (Stoßlüften), where all windows are opened simultaneously, fully and briefly, to minimise energy wastage. However, the predominant design of windows in Germany's housing stock mit...

This book focuses on thermal retrofits of homes in Germany, but its findings have a much wider application than that one country. Germany is one of a number of northwest European countries that have taken major strides in recent decades to reduce domestic heating fuel consumption: not only by continually tightening the thermal standards for new bui...

It is now well established that there is a serious gap between normative Energy Performance Certificate (EPC) calculations and measured energy consumption in the domestic sector. The fact that there are similarities in this gap between different European countries with varied housing stocks, different normative (EPC) dwelling consumption calculatio...

German Federal policy on thermal renovation of existing homes was evaluated in terms of how well it is achieving its stated goal of reducing GHG emissions from home heating by 80% within 40 years. The study examined both the technical efficacy of the policy in relation to the actual built environment in which it is set, and the prevailing policy di...

In the domestic heating sector a number of different mathematical models are used to evaluate the economic viability of thermal retrofit measures. Currently, however, none of these models incorporate the effect of fuel price elasticity of demand. This paper offers a method for incorporating a factor for fuel price elasticity into models for assessi...

German regulations for the thermal renovation of existing homes demand high thermal standards, which the government claims are technically and economically feasible. This paper examines existing data on 3400 German homes; their calculated energy performance ratings (EPR) are then plotted against the actual measured consumption. The results indicate...

Discourse theories offer a penetrating approach to environmental policy analysis, as they focus on the interpretive worlds produced in policy actors' utterances and writings, and the argumentative struggles that lead to one view dominating over others in a policy domain. However they fail to theorise the relationships between policy discourse and t...

High humidity can lead to condensation and mould formation if a house is well sealed and indoor temperatures fall significantly during the night. Solutions that have been offered are to keep heaters on throughout the night, to increase the thickness of insulation, or to install heat-exchange ventilators. These solutions are expensive. The cultural...

One of the cheapest ways to reduce CO2 emissions is thermal renovation of existing homes. Germany is a world leader in this project, with a strict building code, generous state subsidies, and an advanced renovation infrastructure. The effects of its policies are here explored in the light of progressive tightening of the building code, and the stri...

German state subsidies for photovoltaic (PV) electricity generation now amount to over 200 million euros per month. Yet PV in Germany is only 30% as economically efficient as wind power, while up to 19 times as much energy would be saved if the same funds were used to thermally renovate homes. The generous subsidy has led to increasing demand for P...

Sub-national governments are now seen as having an important role to play in climate protection. Initial research in this area sought to identify their initiatives in climate change mitigation and theorize their role in relation to national and international climate protection policies. Because of the wide variations of constitutional arrangements...

Experts in the natural sciences are frequently commissioned by governments to provide scientific input for policy development. But it is impossible to do this without importing scientists' own values and political commitments into their models and reports, since their advice has to be tailored to interface with a social setting and cultural context...