Disaggregating the causes of falling consumption of domestic heating energy in Germany

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 deep thermal retrofits through regulation, information campaigns and subsidised loans. An important question is what portion of the reductions are due to progressive energy efficiency upgrade policy and what are due to other, non-technical factors such as demographic and behaviour change. We use national statistics and existing empirical studies to disaggregate the contribution of energy-efficiency improvements and nontechnical factors to the reduction in consumption. Our analysis suggests that around 20 % of the reductions are likely to be due to thermal retrofits of existing dwellings (insulation and new windows), 31 % due to boiler or heating system replacements, 1 % due to replacement of old dwellings with new, energy-efficient buildings, while some 45–50 % of the savings cannot be explained by these technical improvements. Most of these reductions appear to have occurred in non-upgraded, non-new dwellings. Although we do not know what caused these reductions, the finding is robust to very wide inaccuracies in figures for savings through technical improvements in buildings’ energy efficiency. More research is needed to explore the extent to which this implies increasing fuel poverty, increasing skills and motivation among non-poor households to heat more economically, or the effects of demographic and lifestyle changes. Highlights ? German home heating energy consumption fell by 105 TWh in 2000–2011 ? Approximately 31 % of this was due to boiler/heating system upgrades ? Approximately 20 % was due to window replacement and thermal envelope upgrade ? Less than 1 % was due to replacement of old with new stock ? Over 45 % cannot be explained by technical upgrade factors ? This could imply rising fuel poverty or more skilful heating behaviour     

German Energiewende and the heating market – Impact and limits of policy

The German Energiewende envisages achieving a climate-neutral building stock in 2050 by means of two major pillars of regulation. First, residential buildings should consume 80% less primary energy and second; the remaining energy demand should be covered primarily with renewables. This paper simulates the future German heating market under different policy scenarios in order to evaluate the impact and limits of recent and conceivable policies. The investigation is based upon a dual model approach, linking a residential heating model to a discrete choice model. The major finding is that current regulations are not suitable for the achievement of governmental targets. Scenario calculations show that additional carbon emission reductions, triggered by the current regulatory regime, are falling short of expectations. In terms of economic efficiency, all calculated policy alternatives outperform the regulation currently in place. This allows to draw the conclusion that carbon emission reductions can be achieved without a major increase in cost. The model results highlight two policy implications. First, a rising mandatory share of renewables in the heating market is needed for target achievement and can be cost effectively. Second, renewable obligations for heating systems must include the existing building stock to achieve the postulated political targets.     

The savings of energy saving: interactions between energy supply and demand-side options—quantification for Portugal

Reducing demand by increasing end-use energy efficiency on the demand side of energy systems may also have advantages in reducing fossil dependency and greenhouse gas (GHG) emissions on the supply side. This paper addresses interactions between energy supply- and demand-side policies, by estimating the impact of measures addressing end-use energy efficiency and small-scale renewables uses in terms of (1) avoided large-scale electricity generation capacity, (2) final energy consumption, (3) share of renewables in final energy and (4) reduction of GHG emissions. The Portuguese energy system is used as a case study. The TIMES_PT bottom-up model was used to generate four scenarios covering the period up to 2020, corresponding to different levels of efficiency of equipment in buildings, transport and industry. In the current policy scenario, the deployment of end-use equipment follows the 2000–2005 trends and the National Energy Efficiency Action Plan targets. In the efficient scenarios, all types of equipment can be replaced by more efficient ones. Results show that aggressive demand-side options for the industry and buildings sector and the small-scale use of renewables can remove the need for the increase in large-scale renewable electricity capacity by 4.7 GW currently discussed by policy makers. Although these measures reduce total final energy by only 0–2 %, this represents reductions of 11–14 % in the commercial sector, with savings in total energy system costs of approximately 3,000 million euros₂₀₀₀—roughly equivalent to 2 % of the 2010 Portuguese GDP. The cost-effectiveness of policy measures should guide choices between supply shifts and demand reduction. Such balanced policy development can lead to substantial cost reductions in climate and energy policy.     

How ambitious are China and India’s emissions intensity targets?

Several developing economies have announced carbon emissions targets for 2020 as part of the negotiating process for a post-Kyoto climate policy regime. China and India’s commitments are framed as reductions in the emissions intensity of the economy by 40–45% and 20–25%, respectively, between 2005 and 2020. How feasible are the proposed reductions in emissions intensity for China and India, and how do they compare with the targeted reductions in the US and the EU? In this paper, we use a stochastic frontier model of energy intensity to decompose energy intensity into the effects of input and output mix, climate, and a residual technology variable. We use the model to produce emissions projections for China and India under a number of scenarios regarding the pace of technological change and changes in the share of non-fossil energy. We find that China is likely to need to adopt ambitious carbon mitigation policies in order to achieve its stated target, and that its targeted reductions in emissions intensity are on par with those implicit in the US and EU targets. India’s target is less ambitious and might be met with only limited or even no dedicated mitigation policies.     

Analysis on the carbon trading approach in promoting sustainable buildings in China

With the high growth urbanization and increasing new urban population, the huge demand for infrastructures and dwellings has become a great challenge for the sustainable development in Chinese cities. The building sector shares one fourth of total energy consumption in the country and plays an important role in reducing the energy consumption and the consequential green house gas (GHG) emissions. Some policies have been issued for promoting the low carbon sustainable development in China's buildings. However, existing barriers especially the investment barriers substantially prevent the low carbon technologies and service from being employed effectively. The carbon trading scheme of cap-and-trade is now widely accepted as one cost-effective way to deal with the climate change issue in the world, and it can be utilized for overcoming the barriers to carbon reduction activities in China's building sector. A new Clean Development Mechanism (CDM) energy performance based method is designed for reducing transaction costs in implementing CDM projects in China's buildings before 2020. And then a “step by step” approach is formed to establish the domestic and international carbon trading mechanism to effectively reduce GHG missions in China's building sector after 2020.     

Recent estimates of energy efficiency potential in the USA

Understanding the potential for reducing energy demand through increased end-use energy efficiency can inform energy and climate policy decisions. However, if potential estimates are vastly different, they engender controversial debates, clouding the usefulness of energy efficiency in shaping a clean energy future. A substantive question thus arises: is there a general consensus on the potential estimates? To answer this question, this paper reviews recent studies of US national and regional energy efficiency potential in buildings and industry. Although these studies are based on differing assumptions, methods, and data, they suggest technically possible reductions of ~25–40 % in electricity demand and ~30 % in natural gas demand in 2020 and economic reductions of ~10–25 % in electricity demand and ~20 % in natural gas demand in 2020. These estimates imply that electricity growth from 2009 to 2020 ranges from turning US electricity demand growth negative, to reducing it to a growth rate of ~0.3 %/year (compared to ~1 % baseline growth).     

The effect of energy performance regulations on energy consumption

Governments have developed energy performance regulations in order to lower energy consumption in the housing stock. Most of these regulations are based on the thermal quality of the buildings. In the Netherlands, the energy efficiency for new buildings is expressed as the EPC (energy performance coefficient). Studies have indicated that energy regulations are successful in lowering the energy consumption in residential buildings. However, the actual energy consumption is usually different from the expected energy consumption. This paper explores the effectiveness of energy performance regulations in lowering the energy consumption of dwellings built in the Netherlands after 1996. The effect of the EPC and thermal characteristics on energy consumption was determined by statistical analyses of data on actual energy consumption. The results showed that energy reductions are seen in dwellings built after the introduction of energy performance regulations. However, results suggest that to effectively reduce energy consumption, the tightening of the EPC in not enough. Policies aimed at controlling the construction quality and changing occupant behaviour are also necessary to achieve further energy reductions.     

Interactions and implications of renewable and climate change policy on UK energy scenarios

As a response to the twin challenges of climate change mitigation and energy security, the UK government has set a groundbreaking target of reducing the UK’s economy-wide carbon emissions by 80% from 1990 levels by 2050. A second key UK energy policy is to increase the share of final energy consumption from renewables sources to 15% by 2020, as part of the wider EU Renewable Directive. The UK’s principle mechanisms to meet this renewable target are the Renewable Obligation (RO) in the electricity sector, the Renewable Transport Fuel Obligation (RTFO), and most recently the Renewable Heat Programme (RHP) for buildings. This study quantifies a range of policies, energy pathways, and sectoral trade-offs when combining mid- and long-term UK renewables and CO₂ reduction policies. Stringent renewable policies are the binding constraints through 2020. Furthermore, the interactions between RO, RTFO, and RHP policies drive trade-offs between low carbon electricity, bio-fuels, high efficiency natural gas, and demand reductions as well as resulting 2020 welfare costs. In the longer term, CO₂ reduction constraints drive the costs and characteristics of the UK energy system through 2050.     

The influence of the Energy Performance Certificate: The Dutch case

All European Union Member States require an Energy Performance Certificate (EPC) when buildings are constructed, sold and rented. At its introduction the EPC was considered a pioneering instrument, one that would help overcome an information deficit hindering consumer interest in energy efficient dwellings. Now that the EPC has been implemented for several years it is possible to examine its impact. This research draws on data from ex-ante and ex-post assessments of the EPC in a number of countries and presents the results of a survey of Dutch private dwelling purchasers. This survey was based on two sample populations, one received an EPC during property transaction and another did not. Differences were sought between the two samples in a number of areas relating to the adoption of energy efficiency measures. Results show that many projections about the impact of the EPC have fallen short. The EPC was found to have a weak influence, especially pre-purchase. The potential of the EPC in driving energy efficiency improvement in the existing stock is doubted especially if it continues to act independent from a mix of instruments designed to tackle multiple barriers. It is argued that the energy saving potential of existing dwellings, applauded in climate change policy, will remain unexploited if it continues to be assessed subjectively by householders.     

The macroeconomic rebound effect and the world economy

This paper examines the macroeconomic rebound effect for the global economy arising from energy-efficiency policies. Such policies are expected to be a leading component of climate policy portfolios being proposed and adopted in order to achieve climate stabilisation targets for 2020, 2030 and 2050, such as the G8 50% reduction target by 2050. We apply the global “New Economics” or Post Keynesian model E3MG, developing the version reported in IPCC AR4 WG3. The rebound effect refers to the idea that some or all of the expected reductions in energy consumption as a result of energy-efficiency improvements are offset by an increasing demand for energy services, arising from reductions in the effective price of energy services resulting from those improvements. As policies to stimulate energy-efficiency improvements are a key part of climate-change policies, the likely magnitude of any rebound effect is of great importance to assessing the effectiveness of those policies. The literature distinguishes three types of rebound effect from energy-efficiency improvements: direct, indirect and economy-wide. The macroeconomic rebound effect, which is the focus of this paper, is the combination of the indirect and economy-wide effects. Estimates of the effects of no-regrets efficiency policies are reported by the International Energy Agency in World Energy Outlook, 2006, and synthesised in the IPCC AR4 WG3 report. We analyse policies for the transport, residential and services buildings and industrial sectors of the economy for the post-2012 period, 2013–2030. The estimated direct rebound effect, implicit in the IEA WEO/IPCC AR4 estimates, is treated as exogenous, based on estimates from the literature, globally about 10%. The total rebound effect, however, is 31% by 2020 rising to 52% by 2030. The total effect includes the direct effect and the effects of (1) the lower cost of energy on energy demand in the three broad sectors as well as of (2) the extra consumers’ expenditure from higher (implicit) real income and (3) the extra energy-efficiency investments. The rebound effects build up over time as the economic system adapts to the higher real incomes from the energy savings and the investments.     

Defining nearly zero-energy housing in Belgium and the Netherlands

Europe expects the housing sector to evolve towards ??nearly zero-energy?? dwellings. Meanwhile, general terms and research, marketing and legal definitions considering such dwellings have already been introduced. Appraisal of existing definitions is now needed for further policy development. This paper examines what nearly zero-energy terms can be expected to be adopted in Belgium and the Netherlands. The research method uses an interview method based on innovation diffusion theory. The analysis traces the regional adoption trajectory of relevant definitions and examines the opportunities and barriers for the inclusion of existing definitions in regional energy policy. The analysis shows that??whilst international prominence of the terms ??net zero energy?? and ??net zero carbon??, in addition to ??low energy?? and ??passive house??, is observed??in Belgium and the Netherlands ??passive house?? and ??energy neutral?? are preferred. The research findings indicate that the adoption of already existing definitions for nearly zero-energy houses will depend on the region and can prove a very complex process with several conflicting issues. Terms should be clearly defined and used at all political and marketing levels. It is recommended to enhance the relative advantage, demonstrability, visibility and compatibility of favoured definitions by policy initiatives.     

What is the relationship between built form and energy use in dwellings?

Energy is used in dwellings to provide four services: space heating, hot water, lighting and to power appliances. This paper describes how the usage of energy in a UK home results from a complex interaction between built form, location, energy-using equipment, occupants and the affordability of fuel. Current models with standard occupancy predict that energy use will be strongly related to size and built form, but surveys of real homes show only weak correlations, across all types of dwelling. Recent research has given us insights into occupancy factors including preferred comfort, ‘take-back’ from thermal efficiency improvements, and patterns of electricity use. Space heating is on a downward trend and is low in new dwellings. Energy use for lights and appliances, which is only weakly related to built form, is increasing. Strong legislation, combined with low-carbon technologies, will be needed to counteract this trend. Future challenges discussed include increases in real energy prices and climate change mitigation efforts, which are likely to improve the existing stock. Challenging targets are now in place for new housing to move towards low or zero energy and carbon standards. In the longer term, dwellings will demand less energy. Alternatives to gas for space heating will be increasingly common, including ground source heat and local combined heat and power (CHP) from biomass, while electricity could come from a more decarbonised electricity system. However, these improvements must be set alongside a demand for many new homes, demographic trends towards smaller households, and a more holistic approach to overall carbon use including personal transport.     

How to support growth with less energy

Economic growth with less use of primary energy and lower carbon emissions can be achieved through existing and new technical solutions and by behavioural change. These solutions secure growth with lower carbon emissions and reduce our dependence on oil and gas, thereby improving security of energy supply. The implication of the Energy White Paper goal of reducing CO₂ emissions by 60% by 2050 is a six-fold reduction in the carbon intensity of the UK economy, and further reductions will be needed. Efficient and renewable supply, distribution and end-use technologies have multiplicative effects, but constraining demand growth is crucial to the rate and extent of reducing emissions. Goals include reductions in the energy intensity of transport and buildings and in the energy intensity of major building materials with the development of technologies and demand management. There will also need to be infrastructural developments that encourage low-carbon technologies and increase energy diversity and security of supply, better low-carbon planning and improved co-ordination of planning, building control and other policy tools, better monitoring and feedback on the real performance of energy-efficient technologies, and improved capabilities to model whole energy systems, including demand and supply as well as social and economic issues.     

Long-term energy savings and greenhouse gas emission reductions in the Swiss residential sector

The aim of this paper is to explore the possibilities to reach two long-term targets regarding energy consumption and greenhouse gas emissions of the Swiss residential building stock: a reduction of the final energy consumption by a factor of 3 and of _CO2${\mathrm{CO}}_2$ emissions by a factor of 5 until 2050. A model is constructed to describe the dynamics of the energy-relevant properties of the residential building stock. Appropriate scenarios are discussed in terms of decisions made during construction or renovation of residential buildings which affect heat demand and determine the energy carriers used for heating and hot water generation. We show that both targets could be reached, although ambitious efforts are necessary. The central element of a successful strategy is to reduce the specific heat demand of existing buildings during renovation and to substitute the heating and hot water systems by less carbon intensive ones. Our results suggest that there is more flexibility to reach the emission target than the energy reduction target.     

New build: Materials,techniques, skills and innovation

The transition to secure, sustainable, low-energy systems will have a significant effect on the way in which we design and construct new buildings. In turn, the new buildings that are constructed will play a critical role in delivering the better performance that would be expected from such a transition. Buildings account for about half of UK carbon dioxide (CO₂) production. So it is urgent to ensure that energy is used efficiently in existing buildings and that new building stock is better able to cope with whatever the future holds.     

The role of energy efficiency in reducing Scottish and UK CO2 emissions

In 2003, the UK government launched its long-anticipated White Paper on energy, the centrepieces of which were ambitious targets for the production of electricity from renewable technologies and the long-term aspiration of a 60% reduction in UK greenhouse gas emissions by 2050. In the White Paper it was recognised that such a dramatic reduction in emissions will require significant changes in the way in which energy is produced and used. However there has been a general failure to recognise the fact that in order to meet emissions targets, the UK will have to significantly reduce its energy consumption; this is not helped by the general misconception in the UK that reductions in CO₂ emissions will occur simply by increasing the production of electricity from renewable sources.

Specifically, this paper highlights the current trends in renewables deployment and energy demand, with a specific focus on Scotland, where the authorities have set more ambitious renewables targets than the rest of the UK. As will be demonstrated in this paper, without energy demand reduction, the deployment of renewables alone will not be sufficient to curtail growth in UK CO₂ emissions. This is illustrated using a case study of the Scottish housing sector; whilst this case study is necessarily local in scope, the results have global relevance. The paper will also address the magnitude of energy savings required to bring about a reduction in emissions and assesses the status of the policies and technologies that could help bring such reductions about.     

Energy efficiency in the British housing stock: Energy demand and the Homes Energy Efficiency Database

The UK Government has unveiled an ambitious retrofit programme that seeks significant improvement to the energy efficiency of the housing stock. High quality data on the energy efficiency of buildings and their related energy demand is critical to supporting and targeting investment in energy efficiency. Using existing home improvement programmes over the past 15 years, the UK Government has brought together data on energy efficiency retrofits in approximately 13 million homes into the Homes Energy Efficiency Database (HEED), along with annual metered gas and electricity use for the period of 2004–2007.This paper describes the HEED sample and assesses its representativeness in terms of dwelling characteristics, the energy demand of different energy performance levels using linked gas and electricity meter data, along with an analysis of the impact retrofit measures has on energy demand. Energy savings are shown to be associated with the installation of loft and cavity insulation, and glazing and boiler replacement. The analysis illustrates this source of ‘in-action’ data can be used to provide empirical estimates of impacts of energy efficiency retrofit on energy demand and provides a source of empirical data from which to support the development of national housing energy efficiency retrofit policies.     

Altering existing buildings in the UK

The profiles of both existing housing and existing public and commercial buildings show that many have very poor thermal efficiency. The UK housing stock is replaced at a low rate of about 1% a year, so to cut energy use it is essential to address the challenges of existing buildings. This will involve reducing energy demand through passive measures such as retrofitted insulation, replacement of windows and proper airtightness, while ensuring adequate ventilation. Active measures include upgrading improved boilers and adding locally produced energy from wind, biomass, solar power and other sources. The introduction of Display Energy Certificates will increase energy awareness but there will also need to be a programme of increased demolition for the worst-performing homes. In addition, buildings will need to be adapted to cope with worse weather, higher temperatures and increased flood risk as climate change takes effect. Overheating, rather than excessive cold, is set to become a growing problem for householders and employees in existing UK buildings.     

Policy measures to overcome barriers to energy renovation of existing buildings

Even though there is great potential to reduce greenhouse gas emissions from existing buildings, most political effort in Korea has been focused on the construction of new buildings; few concrete measures have been taken to limit greenhouse gas emissions from existing buildings. This study examined the potential to reduce greenhouse gas emissions from existing residential buildings as a means to cope with global warming. Additionally, several barriers to improving the energy performance of existing dwellings instead of constructing new dwellings were explored. The major barriers to improving the energy performance of existing residential buildings are: (1) a lack of awareness; (2) financial reasons; (3) insufficient information; and (4) the absence of regulatory systems. To overcome such barriers, systems adopted and implemented in developed European countries were considered and their feasibility was verified so that political measures could be suggested to improve the energy performance of existing dwellings in Korea.     

Reductions in emissions of local air pollutants and co-benefits of Chinese energy policy: a Shanghai case study

To better understand the reductions in local air pollution that will result from the implementation of current Chinese energy policy, as well as the co-benefit for greenhouse-gas emission reductions, a Shanghai case study was conducted. The MARKAL model was used to forecast energy consumption and emissions of local air pollutants under different energy policy scenarios and also to analyze the associated reductions in CO₂ emissions. The results show that energy policies in Shanghai will significantly reduce SO₂ and PM₁₀ emissions and will also achieve the co-benefit of mitigating the increase of CO₂ emissions. In energy policy scenarios, SO₂ emissions during the period 2000–2020 will maintain the same level as in 2000; and the annual rate of increase of CO₂ emissions will be reduced to 1.1–1.2%, compared with 2.7% under a business-as-usual scenario. The problem for the future will be NO_x emissions, which are projected to increase by 60–70% by 2020, due to expansion of the transportation system.