Modelling the potential to achieve deep carbon emission cuts in existing UK social housing: The case of Peabody

As part of the UK’s effort to combat climate change, deep cuts in carbon emissions will be required from existing housing over the coming decades. The viability of achieving such emission cuts for the UK social housing sector has been explored through a case study of Peabody, a housing association operating in London. Various approaches to stock refurbishment were modelled for Peabody’s existing stock up to the year 2030, incorporating insulation, communal heating and micro-generation technologies. Outputs were evaluated under four future socio-economic scenarios. The results indicate that the Greater London Authority’s target of a 60% carbon emission cut by 2025 can be achieved if extensive stock refurbishment is coupled with a background of wider societal efforts to reduce carbon emissions. The two key external requirements identified are a significant reduction in the carbon intensity of grid electricity and a stabilisation or reduction in householder demand for energy. A target of achieving zero net carbon emissions across Peabody stock by 2030 can only be achieved if grid electricity becomes available from entirely zero-carbon sources. These results imply that stronger action is needed from both social landlords and Government to enable deep emission cuts to be achieved in UK social housing.     

Small might be beautiful,but bigger performs better: Scale economies in “green” refurbishments of apartment housing

The energy efficiency of the residential housing stock plays a key role in strategies to mitigate climate change and global warming. In this context, it is frequently argued that private investment and the quality of thermal upgrades are too low in the light of the challenges faced and the potential energy cost savings. While many authors address the potential barriers for investors to increase energy efficiency, studies on the capabilities of different investors to reduce energy requirements of their property are scarce. This study investigates potential advantages of housing company's size, i.e. economies of scale, economies of scope and institutional learning in thermal upgrades of residential housing. Based on unique data on energy consumption in 102,307 apartment buildings in Germany, we present new evidence for the advantages and disadvantages of a housing company's size in “green” retrofitting projects. Our estimations show, that large housing companies outperform private landlords by far in high effort refurbishment projects. In contrast, private landlords appear to have advantages in low effort, incremental refurbishment activities. We demonstrate that a substantial share of the advantages of larger firms can be associated with specialization (i.e. repeated projects). The results offer new options for policy makers to refine the support schemes toward a low carbon housing stock.     

Guided group purchases of energy renovation services and works in deprived urban neighbourhoods

The energy retrofitting of housings is progressing very slowly in Wallonia (Belgium) despite individual fiscal measures and subsidies offered by public authorities to support households engaging in this process. This paper explores the use of a method called ‘guided group purchases’ (GPPs), i.e. an approach combining support, guidance and group purchasing of energy renovation services and works as a possible method to accelerate the retrofitting of the existing housing stock. It reports on an action research experiment conducted in the context of the Interreg project ‘sustainable urban neighbourhoods’ (SUN). The results of this experiment are quite promising. Within a few months, some 80 energy retrofitting interventions (energy audits or insulation works) were implemented in one neighbourhood of the city of Liège. Our evaluation of the experiment showed that the prospect of achieving cost reductions was one of the main initial expectations of participants to the GGPs. Still, the participants rather insisted on other benefits after taking part in the initiative. These benefits were mostly related to the guidance they received, to the facilitation with contractors and to the social dynamics generated by the initiative. Several weaknesses were also identified by the participants, like the lack of follow-up during and after the works. Our evaluation also highlighted that the main landlords did not participate in the initiative and that the influence of GGPs on costs was limited to specific types of interventions. Despite observed limitations and possible improvements, such a neighbourhood-based approach certainly constitutes a promising avenue for public authorities to support and accelerate the energy retrofitting of private residential buildings in urban neighbourhoods.     

Domestic futures—Which way to a low-carbon housing stock?

This paper examines various routes to achieving a 60% carbon emission reduction from the UK housing stock by 2050 compared to 1996, using a new object-oriented housing stock and carbon model, DECarb. As housing is at present responsible for 26% of all UK emissions, housing carbon reduction is likely to be a key component for the overall 60% emission reduction target set by the UK Government's Energy White Paper in 2003. This paper compares 3 independently published sets of scenarios detailing possible routes and suggests that highly disaggregated approaches produce more credible data. The results also show that whilst there are many different routes to achieving the target from a technological standpoint, all of them will require significant shifts in current practice. We investigate other routes to achieving this target, while also meeting nearer term reductions of 50% by 2030. DECarb shows that significant challenges exist in meeting these requirements, though they are technically feasible. On this basis it also becomes clear that the domestic sector will not be able to offset smaller reductions from any other sector of the economy.     

Evaluating the impact of energy interventions: home audits vs. community events

New Zealand’s housing stock tends to be of low thermal quality that can adversely affect the health and well-being of occupants as well as costing more than necessary to heat. Householders need information and motivation to make material changes and adopt new practices to achieve warmer and more energy-efficient homes. This study compares two different types of energy interventions with householders in three different suburbs in Dunedin, New Zealand. Two suburbs received a home energy audit whereby an auditor surveyed each house and provided personalised advice. Householders in the third suburb took part in community energy events that included general advice and practical workshops. The impacts of these interventions were evaluated through pre- and post-intervention surveys and post-intervention interviews. Home energy audits were successful in encouraging change both behavioural and practical, where it was possible. The energy events promoted community engagement and awareness relating to energy-saving actions. Participant feedback suggests that a combination of both types of intervention may be most effective in promoting household change, beginning with energy events in communities before offering home energy audits. This would enable people to share their thoughts and concerns about energy with the support of their social networks and engender trust in the process, before offering personalised audits. Overall, the results show that interventions need to be correctly targeted to appropriate communities to be effective.     

Actual heating energy savings in thermally renovated Dutch dwellings

The register of the Dutch social housing stock was analysed, containing 300.000 dwellings, renovated between 2010 and 2013. The main objective was twofold: to evaluate the performance gap in these dwellings before and after the renovation and to establish what renovation measures achieve the highest reduction of consumption, particularly in practice (actual savings). The results showed large performance gaps in dwellings with low R and high U values, local heating systems, changes from a non-condensing into a condensing boiler and upgrades to a natural ventilation system. Regarding the actual effectiveness of renovation measures, replacement of old gas boilers with more efficient ones yields the highest energy reduction, followed by deep improvements of windows. Installing mechanical ventilation yields a small reduction compared to other measures, but still much larger than theoretically expected. The paper shows once more that the calculation method currently in use cannot be considered accurate if compared to actual consumption. The study demonstrated that unrealistic theoretical efficiencies of heating systems and insulation values are causing a part of the performance gap. Nowadays, large datasets of buildings thermal performance and actual consumption offer an opportunity to improve these misconceptions.     

State of the Irish housing stock—Modelling the heat losses of Ireland's existing detached rural housing stock & estimating the benefit of thermal retrofit measures on this stock

Ireland's housing stock has been identified as being amongst the least energy efficient in Northern Europe. Consequently, atmospheric emissions are greater than necessary. Government funded schemes have been introduced to incentivise the uptake of thermal retrofit measures in the domestic Irish market. A study of Ireland's housing highlights the dominance of detached houses (43%), 72% of which are rurally located and are predominantly heated with fuel oil. This paper investigates the economic and carbon case for thermal retrofit measures to the existing detached, oil centrally heated, rural housing stock. The study found the case for energy efficiency measures to be categorical and supports the Irish Government's focus on energy efficiency policy measures. Thermal retrofit measures in the detached housing stock have the potential to realise an averaged 65% theoretical reduction in heating costs and CO₂ emissions for houses constructed prior to 1979 (coinciding with the introduction of building regulations) and around 26% for newer homes, thus offering a significant contribution (44%) to Ireland's residential carbon abatement projections and hence in meeting the EU's directives on energy and carbon. The greatest savings (36%) of Ireland's carbon abatement projections result from improving the energy efficiency of the pre 1979 stock.     

An exploration of the technical feasibility of achieving CO2 emission reductions in excess of 60% within the UK housing stock by the year 2050

The aim of this paper is to explore the technological feasibility of achieving CO₂ emission reductions in excess of 60% within the UK housing stock by the middle of this century. In order to investigate this issue, the paper describes the development of a selectively disaggregated physically based bottom-up energy and CO₂ emission model of the UK housing stock. This model covers both the energy demand and energy supply side and has been used to develop and evaluate three illustrative scenarios for this sector. The results of the scenarios suggest that it may be technically easier, using currently available technology, to achieve CO₂ emission reductions in excess of 80% within the UK housing stock by the middle of this century. However, achieving these sorts of reductions will require strategic shifts in both energy supply and demand side technology.     

Beyond economics—understanding the decision-making of German small private landlords in terms of energy efficiency investment

The German government aims to achieve virtually climate-neutral building stock by 2050 to tackle climate change. To realise this goal, comprehensive policy packages based on neoclassical economic theory are in place to foster energy efficiency investment. However, in the building sector, there is increasingly a gap between this aspiration and the reality. It is claimed that one of the main reasons for this is that the existing policy framework fails to address the specific characteristics and needs of different groups of building owners. This is a particular challenge in Germany, where 80% of all dwellings are owned privately and 37% are rented out by small private landlords (SPL). Despite the significant numbers of SPL, they often follow black box decision-making processes when considering energy renovations. In this study, the author uses an explanatory model to understand the decision-making processes of SPL, combining theoretical aspects from different research disciplines. This model was applied to a low-demand housing market in a neighbourhood in the Ruhr area. Eighteen semi-structured interviews (each lasting between 37 and 115 min) were conducted, demonstrating that in addition to economic factors, the values, beliefs, norms and routines of SPL—as well as their personal capabilities and contextual factors—play an important role in their decision-making. Based on the findings, recommendations are made for enhancing the effectiveness of existing energy efficiency policies and other supporting instruments (e.g. tenancy law and social legislation), tailored to the specific needs of SPL.     

Assessment of current Dutch energy transition policy instruments for the existing housing stock

This research assesses to what extent current Dutch energy transition policy instruments for the existing housing stock can fulfil local executive actors’ needs and instigate adoption of energy efficiency measures by them. This is done by studying energy policy instruments for the existing housing stock in the Netherlands and in other European countries, and by an empirical research, which analyses barriers and needs of local executive actors. We found that, despite current Dutch energy transition policy instruments for the existing housing stock seem to fulfil local executive actors’ needs to a large extent, complementary policy instruments are needed to stimulate and pressure the incumbent renovation regime. A long-term oriented financial rewarding system is needed to build up a structural market for the deployment of renewables, to increase the number of specialist jobs in the building sector, and to stimulate the development of integrated, standardized, building components. Furthermore, a long-term oriented financial rewarding system for energy efficiency investments in housing renovation projects, and a low VAT rate applied to energy efficient renovation measures, are needed. Finally, enforcement possibilities and sanctions (fines) should become an integrative part of Dutch energy certification regulation to make the certificate become part of a value chain.     

Leveraging energy efficiency to finance public-private social housing projects

The Italian housing model relies on a high rate of privately owned houses. In comparison, few dwellings are built and managed by the public sector. The social housing stock has been built mainly during some post-second world war decades; instead, since the early nineties, it underwent a privatization process.Such a model is inefficient and iniquitous in the long run. Therefore, after being disregarded for several years, social housing has gone back to be among the main agenda items. Nonetheless, due to the lack of public grants, new funding sources are required. The government now fosters an increasing involvement of private finance through Public-Private Partnership schemes.A first outcome can be found in some pioneering experiences. Their comparative analysis allows bringing out worthwhile findings, which are useful to steer housing policies. Moderate to low yields entail the need to involve new kinds of private entities, particularly those adopting a venture philanthropy approach. Meanwhile, building energy performance measures are a crucial driver of feasibility. They allow the tenants to be willing to pay agreed rents somehow higher than both social rents of protected tenancies and fair rents of regulated tenancies.     

Modelling the UK residential energy sector under long-term decarbonisation scenarios: Comparison between energy systems and sectoral modelling approaches

The UK government has set a groundbreaking target of a 60% reduction in carbon dioxide (CO₂) emissions by 2050. Scenario and modelling assessment of this stringent target consistently finds that all sectors need to contribute to emissions reductions. The UK residential sector accounts for around 30% of the total final energy use and more than one-quarter of CO₂ emissions. This paper focuses on modelling of the residential sector in a system wide energy–economy models (UK MARKAL) and key UK sectoral housing stock models. The UK residential energy demand and CO₂ emission from the both approaches are compared. In an energy system with 60% economy-wide CO₂ reductions, the residential sector plays a commensurate role. Energy systems analysis finds this reduction is primarily driven by energy systems interactions notably decarbonisation of the power sector combined with increased appliance efficiency. The stock models find alternate decarbonisation pathways based on assumptions related to the future building stock and behavioural changes. The paper concludes with a discussion on the assumptions and drivers of emission reductions in different models of the residential energy sector.     

The value of retrofitting carbon-saving measures into fuel poor social housing

With current fuel poverty and carbon-saving policies continuing to miss their targets in the UK, the synergy between the two problems is investigated to highlight an approach that could be mutually beneficial. Focussing on the 550,000 fuel poor socially housed dwellings in the UK, costs of between £3.9 and £17.5 bn are estimated as the required capital investment for achieving deep-cut carbon savings (defined as at least 50%) across this section of the housing stock, with a potential total annual carbon saving of 1.7 MtCO₂. It is assumed that such costs would be largely (or totally) state-funded, though additional private investment could clearly increase the possible carbon savings across this section of the stock. The use of these socially housed fuel poor dwellings as low-carbon exemplars is discussed, and benefits for the private housing sector are postulated. The study also focuses on the problem of installing non-cost effective measures, i.e. technologies that would not currently be encouraged by existing subsidy schemes, but which might be necessary for achieving large carbon-saving targets.     

Policy progress in mitigation of climate change in Taiwan

To make an active contribution to the global effort in mitigation of climate change, Taiwan government has implemented the “Frameworks for Sustainable Energy Policy—An Energy-Saving and Carbon-Reduction Action Plan” in June 2008. It has made a commitment of a stepwise reduction of nationwide greenhouse gas (GHG) emissions, which returns the nationwide GHG emission to 2008 levels by 2020, then reduces to 2000 levels by 2025, and finally cuts 50% of 2000 levels by 2050. The fundamental strategy is to reduce the GHG emission under acceptable economic development and energy security to achieve generation-spanning triple-win in energy, environment and economy. The major policy instruments such as “Statute for Renewable Energy Development”, “GHG Reduction Law (draft),” “Regulation for Energy Tax (draft),” and “Energy Management Act” have been either implemented or scheduled for legislative reviewing. The purpose of this paper is to present an updated review of the outcomes of GHG emission reduction in Taiwan. In addition, the progress and priority of policy instruments in GHG emission reduction are analyzed as well.     

Abundant low-cost natural gas and deep GHG emissions reductions for the United States

This paper analyzes the implications of the natural gas revolution on the US’ ability to achieve deep GHG emissions reductions of 80% below 2005 levels by 2050. It uses a hybrid energy-economy model to test how prevailing low US natural gas prices influence the magnitude of the required carbon price needed to achieve this target. While the paper finds in general that lower gas prices resulting from plentiful gas necessitate a higher carbon price to achieve this target, informing firms and consumers in advance about the magnitude of the future carbon price can lower the necessary level.     

促进我国自愿碳减排市场发展的对策

评析自愿碳减排市场在国内发展的基本状况。解析我国自愿碳减排市场发展缓慢的主要因素,并提出了未来深入推进我国环境自愿碳减排项目建设的激励政策及创新建议。工业企业实施自愿碳减排已成为国际环境政策发展的潮流和趋势,是促进我国企业自愿碳减排的根本途径。工业企业自愿碳减排项目能否顺利实施,在很大程度上取决于企业内部节能低碳管理系统是否到位。最后提出工业企业实施自愿碳减排项目的方案。     

Stylized agent-based modeling on linking emission trading systems and its implications for China's practice

China established a national emission trading system (ETS) to peak its carbon emission around 2030, building on the experience of pilot ETSs that are planned to be linked. Firms are the main entities that conduct carbon reduction and allowance trading. Due to the heterogeneity in the initial stock of technologies, firms' abatement costs differ, resulting in different abatement activities and the dynamics of the carbon price. Most of the studies on linking ETSs pay little attention to firms' behaviors, especially the interactions among firms' technology adoption strategies and their allowance trading strategies. In addition, whether linking ETSs can reduce carbon emission with lower system costs remains insufficiently explored. This study develops a stylized agent-based model (ABM) to explore the impact of linking two ETSs considering firms' heterogeneities and the interactions between their technology adoption strategies and allowance trading strategies. The model considers two ETSs, each of which includes energy-service-providing agents who are heterogeneous in the production scale and initial stock of technologies (and thus with different abatement costs), and attempts to minimize the total cost for a given output by adopting different technologies and trading emission allowances. The carbon price is dynamically affected by agents' willingness to pay, and a Walrasian auction is introduced to obtain the equilibrium. The results show that linking ETSs could be cost-effective to achieve carbon reduction commitment and creates a larger and more liquid carbon market; however, it also provides agents the opportunity to purchase more allowances rather than adopt low-emission technologies, which may result in more carbon emission. Adding restrictions on the linkage could somehow mediate this negative effect. Imposing strict exchange rate restrictions to the system with more balanced market shares of agents or quantitative restrictions would result in desirable results at the expense of increasing system costs. Moreover, restricted linkages could help alleviate the difficulties in initialing a linkage. The stylized ABM is mainly used for exploratory modeling purposes as a heuristic research device to examine in depth the effectiveness of unrestricted linkages and restricted linkages on adopting low-emission technologies at firms' level and the resulting carbon reduction. On the basis of the main findings of the ABM, we discuss the case if the Hubei pilot ETS links with the Guangdong pilot ETS, which could improve the understanding of the potential impact of linking ETSs on technology adoption and carbon reduction and provide policy implications for linking different ETSs.     

The deployment of decentralised energy systems as part of the housing growth programme in the UK

The housing growth programme could offer an opportunity for accelerating the deployment of decentralised renewable energy systems (DRES) in the UK. The Government hopes to leverage private sector investment into DRES as part of new housing projects. The aim of this paper is to assess whether current regulatory and funding frameworks are sufficient to achieve this. The question is explored by drawing on the experience of developers, local authorities, energy utilities and service companies operating in the largest housing growth region in the UK–Thames Gateway. Their experience suggests that the current low intervention approach will be insufficient to generate the shift required in both industries. In order to be more successful economic and regulatory instruments should focus on producers (house-builders and energy providers) rather than consumers (households). Tighter regulation is needed to ensure that producers have a responsibility to install DRES as part of new developments, to enable connection to the grid, to ensure a sustained financial return from investment and revenue is spent on the expansion of new renewable energy infrastructure. This regulatory framework must be under-pinned by substantial funds focused on producers. Greater intervention is needed if DRES is to be included in new housing development.     

Large CO2 Sinks: Their role in the mitigation of greenhouse gases from an international, national (Canadian) and provincial (Alberta) perspective

Significant reduction of CO₂ emissions on a global scale may be achieved by reduction of energy intensity, by reduction of carbon intensity or by capture and storage of CO₂. A portfolio of these methods is required to achieve the large reductions required; of which utilization of carbon sinks (i.e. material, geosphere and biosphere) will be an important player. Material sinks will probably only play a minor role as compared to biosphere and geosphere sinks in storage of CO₂. Biosphere sinks are attractive because they can sequester CO₂ from a diffuse source whereas geosphere sinks require a pure waste stream of CO₂ (obtained by using expensive separation methods). On the other hand, environmental factors and storage time favor geosphere sinks. It is expected that a combination of the two will be used in order to meet emission reduction targets over the next 100 yr.A critical look is taken at capacities, retention/residence times, rates of uptake and relative cost of utilization of biosphere and geosphere sinks at three scales – global, national (Canada) and provincial (Alberta). Biosphere sinks considered are oceans, forests and soils. Geosphere sinks considered are enhanced oil recovery, coal beds, depleted oil and gas reservoirs and deep aquifers. The largest sinks are oceans and deep aquifers. The other biosphere and geosphere sinks have total capacities approximately of an order of lower magnitude. The sinks that will probably be used first are those that are economically viable such as enhanced oil-recovery, agriculture, forestry and possibly enhanced coalbed methane-recovery. The other sinks will be used when these options have been exhausted or are not available or a penalty (e.g. carbon tax) exists. Although the data tabulated for these sinks is only regarded as preliminary, it provides a starting point for assessment of the role of large sinks in meeting greenhouse gas emission reduction targets.     

Applying California's AB 32 targets to the regional level: A study of San Diego County greenhouse gases and reduction strategies

This paper presents a summary of a local effort in California to assess greenhouse gas (GHG) emissions and identify potential mitigation measures. Local policymakers in California already have been searching for ways to reduce GHG emissions but it was the California Global Warming Solutions Act of 2006 (AB 32), which seeks to reduce GHG emissions to 1990 levels by 2020, that has provided a framework for regions to evaluate their ability to reduce GHG emissions. We conducted a GHG inventory for the San Diego region from 1990 to 2006, with forecasts to 2020. The region emitted approximately 34 million metric tons of carbon dioxide equivalent (MMT CO₂E) in 2006 from anthropogenic sources, which represents a 17% increase over the 1990 level of 29 MMT CO₂E. Applying a combination of 21 existing or pending state GHG reduction mandates and feasible regional measures we show that the region could achieve the AB 32 target. Although the largest reductions are achieved through state mandates, all measures, including at the local level, will be required to achieve the AB 32 target. Thus local regions retain control over a fairly significant portion of reductions, and remain important actors in the implementation and compliance of state mandates.