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921.
Research was conducted in Nottinghamshire, England to investigate public attitudes regarding home energy efficiency issues. Quantitative data were collected in the form of a postal survey, achieving over three hundred responses. Additionally, predominantly qualitative data were collected in semi-structured interviews in 15 homes. The issues investigated included the grant-funded energy efficiency measures installed by the public, the organisations providing grants, the means by which the recipients were referred to the organisations, and the public's preferences regarding energy efficiency advice. Findings were made about the local authority's success in encouraging the take-up of energy efficiency grants, about the public's preferences for the means by which advice should be provided, about trust relating to energy efficiency grants provided by gas and electricity suppliers, and about people's knowledge of the most effective energy efficiency measures. Additional findings were drawn about specific energy efficiency issues, including old heating systems and compact fluorescent light bulbs.  相似文献   
922.
District heating (DH) is an important part of the Swedish energy system and one of the most important climate measures at the municipal level. The Swedish planning system gives a large amount of power to municipalities, thus leaving the regional level weak. Despite this, the DH systems in Stockholm have developed into regional systems; how has this development occurred and what made it possible? Regional and municipal strategies concerning DH and energy from 1978 to 2010 have been studied through Regional plans and comprehensive plans. The conclusions show that the municipal DH systems have grown and become interconnected, thus fulfilling one of the most important regional strategies: to expand and interconnect the systems to be able to build combined heat and power plants. This is not entirely due to the regional strategies, however; the local importance of the system, economic reasons and supply security are other explanations. The study shows that regional importance generally has grown, and thus also the regional focus on DH. As environmental and climate issues have risen on the agenda, the importance of DH from the municipal perspective has become more evident, as well as a shift from supply orientation to more focus on energy efficiency.  相似文献   
923.
The Climate Change Act 2008 commits the UK to reducing carbon emissions by 80% of 1990 levels by 2050. With household emissions constituting more than a quarter of current total energy use in the UK, energy practices in the home have taken on increased policy attention. In this paper, we argue that the UK government's approach is founded upon a variant of methodological individualism that assumes that providing greater energy information to individuals will effect behaviour change in relation to energy use. Such an approach is potentially limited in its effectiveness and does not afford appropriate recognition to all those affected by energy policy. In contrast to this approach, we set out an alternative perspective, a community knowledge networks approach to energy and justice which recognises the contexts and relationships in which people live and use energy. Such an approach emphasises situated knowledge and practices in order to gain a greater understanding of how individuals and communities use energy, but, importantly, offers a means for affording greater recognitional justice to different social groups.  相似文献   
924.
China is the second largest emitter of greenhouse gases (GHG) in the world, with potentially about two thirds of total Certified Emission Reductions (CERs) for Asia on the world carbon market (). Since 68% of its primary energy is from coal, China's average energy intensity is 7.5 times higher than the EU and 4.3 times higher than the US (EU, 2003 The European Union on-line. (2003). (http://europa.eu.int/index_ns_en.htm accessed Oct 2003  [Google Scholar]). Therefore, introducing advanced clean technologies and management to China represents opportunities for Annex I countries to obtain low-cost CERs through CDM projects, and access to one of the largest potential energy conservation markets in the world.

CDM can provide a win-win solution for both China and Annex I countries, and the Chinese government considers that the introduction of CDM projects can bring advanced energy technologies and foreign investment to China, thereby helping China's sustainable economy and generating CERs. As energy efficiency is generally low and carbon intensity is high in both China's energy supply and demand sectors, numerous options exist for cost-effective energy conservation and GHG mitigation with CDM.

This paper reviews current Chinese policies and administrative and institutional settings for CDM cooperation, and discusses existing policy, institutional and other barriers in the energy market by drawing on observations and experience from previous initiatives such as Cleaner Production and energy efficiency. Some options to remove these barriers are addressed. In order to make CDM projects feasible, China's government needs to promote awareness, streamline administrative systems, and be more active in building a competitive edge in the world carbon market.  相似文献   
925.
Recent rapid advances of tidal current energy extraction (TCEE) technologies and resource analyses suggest in excess of 20,000 GWh/annum of electricity may be realistically exploitable in the near term off Canada's West Coast. Moreover, because tidal currents have a semi-diurnal (or, in some locations, diurnal) periodicity, and can be predicted and quantified on a spatial and temporal basis, this resource confers a distinct advantage over most other renewables, and, therefore, may achieve supply security.

In this study, TCEE technologies are assessed on the basis of energy delivered, environmental intrusion and economic viability. As such, relevant issues including resource characteristics, site selection, conversion efficiencies, capacity factors, power densities, hydrodynamic feedbacks, and grid integration are addressed.  相似文献   
926.
Abstract

In this work, low temperature geothermal district heating systems with heat pumps have been studied and compared with fuel-oil boiler heating systems for intermittent and continuous regimes according to the optimum indoor air temperature and operational cost. Izmir Institute of Technology (IZTECH) Campus is taken as a case study. Various heat pump and boiler configurations are studied to meet required duty. Operational cost analysis for each alternative is conducted. According to the results, for IZTECH Campus the best alternative, which gives the optimum indoor air temperature and the lowest operational cost, is heat pump continuous regime.  相似文献   
927.
Abstract

Design and prototyping of a standalone photovoltaic power generation system using the Virtual Test Bed software environment is presented. The design includes establishing physics-based models for components, prototyping system architectures, implementing control algorithms, testing and evaluating the system performance using the actual weather data at a particular geographical location. The dynamic performance of the photovoltaic power system and its components are revealed in great details through the system level simulation. This knowledge is used for verification and improvements of the system design in order to achieve the best system power capability, efficiency and size.  相似文献   
928.
Renewable energy can address rising demand for energy, environmental protection, energy security, and job creation. This paper assesses resource, economic, social, and political drivers for the adoption of renewable energy. Analysis of the data collected from over 100 interviews with utility managers reveals that production tax credits significantly influence the percent of renewable energy in a utility's portfolio. The availability of renewable energy resources, economic drivers, social influences, and political drivers such as renewable portfolio standards and government grants are not significant drivers. Understanding these drivers can help electric utilities, governments, and other stakeholders with their efforts to reap the benefits of renewable energy.  相似文献   
929.
利用密度泛函理论系统地研究了Y_mSi@Al_(12)(m=1—3)团簇及其贮氢性质.结果表明,在所研究的尺度范围内,钇原子未在Si@Al_(12)团簇上团聚;每个钇原子按18电子规则吸附氢分子,其中Y_3Si@Al_(12)团簇可以吸附16个完整氢分子,贮氢质量分数为5.0%,平均吸附能处于0.324—0.527 eV之间,较为理想的吸附能说明在室温条件下吸氢和脱氢是可行的.  相似文献   
930.
我国能源节约战略研究   总被引:14,自引:0,他引:14  
节约能源,保护环境,是全面建设小康社会、实现可持续发展的必不可少的前提条件。中国万美元GDP能耗水平是发达国家的3至11倍。节能潜力很大。其中工业部门是我国的能源消费大户。其能源消费占全国能源消费总量的比重一直保持在70%左右,其节能潜力也居第一位。2020年中国实现全面建设小康社会的目标.人均GDP是3000美元,按届时人口15亿计算,全国GDP为49500亿美元,所需要的能源总量是33亿t标准煤,万美元GDP的能耗是6.67吨标煤;人均能耗是2.13吨标煤。只要政策选择适当。我国完全可以以当初发达国家一半的能源供应实现其相应的人均经济发展目标。为此,我们需要继续建立和完善适应市场经济要求的推动能源节约与资源综合利用的新机制;加快制定与《节约能源法》配套法规,引导和规范用能行为;加快建立以企业为主体的技术创新体系。  相似文献   
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