环境约束下中国省际全要素能源效率实证研究

本文运用基于DEA的方向性距离函数方法测算了1998-2007年环境约束下的中国省际全要素能源效率,并对影响环境约束下全要素能源效率的因素进行了实证检验。研究发现:我国全要素能源效率在样本期间整体处于持续下滑状态,其中西部地区下降的幅度最大;东部地区全要素能源效率最高,其次是中部地区,西部地区最低;广东、辽宁、上海、北京、天津和海南6省市均在生产边界上,而云南、新疆、河北和贵州具有低水平的全要素能源效率;人均GRP、外商直接投资、要素禀赋结构、产业结构、所有制结构、能源结构、企业的环境管理能力以及能源价格都对全要素能源效率有显著影响。因此,全面提升经济发展的水平和质量,均衡地区经济发展,弱化当前我国经济高能耗高产出的特点,是提高我国全要素能源效率的重要手段。     

Concepts of learning and experience in developing solar thermal technologies

This study presents a plausible picture of development of solar thermal technology, using the learning and experience curve concepts. The cost estimates for solar thermal energy technologies are typically made assuming a fixed production process, characterized by standard capacity factors, overhead, and labor costs. The learning curve is suggested as a generalization of the costs of potential solar energy system. The concept of experience is too ambiguous to be useful for cost estimation. There is no logical reason to believe that cost will decline purely as a function of cumulative production, and experience curves do not allow the identification of logical sources of cost reduction directly. The procedures for using learning and aggregated cost curves to estimate the costs of solar technologies are outlined. Because adequate production data often do not exist, production histories of analogous products/processes are analyzed, and learning and aggregated cost curves for these surrogates estimated. If the surrogate learning curves apply, they can be used to estimate solar thermal technology costs. The steps involved in generating these cost estimates are given. Second-generation glass-steel heliostat design concept developed by MDAC is described; a costing scenario for 25,000 units/year is detailed; surrogates for cost analysis are chosen; learning and aggregated cost curves are estimated; and the aggregate cost curve for the MDAC designs is estimated. The surrogate concept of cost estimation combines qualitative steps, which are highly subjective, with quantitative techniques, which require thorough knowledge and understanding to justify their use. As such, the results, interpretations, and inferences must be qualified by an understanding of the process by which they were developed. The method of surrogate learning curves had limitations in both the data acquisition and data analysis phases of activity. Improvements in the validity of cost data and in the task used for this type of study are necessary to enhance the reliability of unit cost predictions resulting from this technique.     

Major transitions in ‘big’ history

‘Big’ history treats events between the Big Bang and contemporary technological life on Earth as a single narrative, suggesting that cosmological, biological and social processes can be treated similarly. An obvious trend in big history is the development of increasingly complex systems. This implies that the degree to which historical systems have deviated from thermodynamic equilibrium has increased over time. Recent theory suggests that step-wise changes in the work accomplished by a system can be explained using steady-state non-equilibrium thermodynamics. This paper argues that significant macro-historical events can therefore be characterized as transitions to steady states exhibiting persistently higher levels of thermodynamic disequilibrium which result in observably novel kinds or levels of organisation. Further, non-equilibrium thermodynamics suggests that such transitions should have particular temporal structures, beginning with sustainable energy innovations which result in novelties in organisation and in control mechanisms for maintaining the new organisation against energy fluctuations. We show how events in big history which qualify as historically significant by these criteria exhibit this internal structure. Big history thus obeys law-like processes, resulting in a common pattern of major transitions between steady-state historical regimes. This common process from cosmological to contemporary times makes big history a viable and relevant field of scientific study.     

The Development and Empirical Testing of Extended Input-Output Price Models

The focus in this paper is on the input-output price model as initially developed by Leontief nearly 60 years ago. A number of methodological refinements are proposed, including the formulation, for the first time, of an extended price model, with a disaggregated household sector. This model is presented in both static and dynamic versions. The effects of these refinements are investigated empirically by reference to an example of policy analysis. This relates to a hypothetical proposal to remove energy subsidies at the national level in Iran. The paper reports on the different results produced by each form of price model and also provides evidence on the sensitivity of individual parameter values. The paper concludes by considering the feasibility of constructing more comprehensive versions of the price model and identifying those elements of the model for which data are likely to be more difficult to obtain at national and regional levels.     

Agency and Control Problems in US Corporations: The Case of Energy-efficient Investment Projects

Private sector corporations in the United States fall short of their potential to increase shareholders'1 wealth in a number of ways. One example is the failure to undertake profitable energy conservation investments. Explanations of this phenomenon include agency and moral hazard problems, imperfect information and incentives, myopia, and X-inefficiency. Data from a survey conducted by the US Environmental Protection Agency and from interviews with corporate executives are used to explore these hypotheses. Good overall corporate performance is found to be associated with longer internal payback requirements for energy investments. Suggestions for improving corporate decision-making in this area are proposed.     

Estimating the long-term effects of utility energy conservation programs: A Pacific Northwest example

The Bonneville Power Administration operated a Residential Weatherization Pilot Program from 1980 through 1982. The program provided free home energy audits to 7200 electrically heated homes in the Pacific Northwest and gave zero-interest loans to weatherize 4100 of these homes. The total cost of the program was almost $11 million.The pilot program and its regionwide successor are intended to provide benefits to the Pacific Northwest region for roughly 30 years in terms of reduced residential energy consumption. Therefore, it is important to determine the durability of the electricity savings due to the program. Estimates of long-term savings affect power supply planning in the region and influence the economics of the program itself (i.e., the level of funding that BPA can justify for the program).This article presents empirical results concerning the total and net energy-saving affects of the BPA pilot program 1, 2, and 3 years after participation. The total annual electricity saving experienced by households that received an energy audit and a weatherization loan averaged 5300 kWh 1 year after participation, increasing to 6000 and 6500 kWh 2 and 3 years after participation, respectively. The net annual electricity saving that can be directly attributed to the program for these audit plus loan households averaged 4500 kWh (15% of preprogram use) 1 year after participation and declined slightly to about 4300 kWh 2 years and 4200 kWh 3 years after participation.The article uses these empirical findings with a simple simulation model to estimate the effects of the program into the future. Assuming that electricity prices remain constant after 1984, total energy savings increase to a level of 7000 kWh, while net energy savings decrease to 3600 kWh for the audit plus loan households. Alternative electricity price scenarios are discussed.     

Wood biomass use for energy in Europe under different assumptions of coal,gas and CO2 emission prices and market conditions

This study examines the effects of different coal, natural gas and carbon emission prices and market situations on the use of wood for electricity and heat production in the European Union. The analysis is carried out using the global forest sector model EFI-GTM expanded to cover electricity and heat production from wood, coal, natural gas, wind and solar energy. Analysis shows that with low coal and gas prices, use of wood for energy will be limited to low cost logging residues. With high coal, and especially natural gas prices, industrial wood also comes to be used for energy. At a carbon price of 100 €/tCO₂, some 32 Mm³ of industrial wood, in addition to 224 Mm³ of logging residues, are projected to be used for electricity and heat in the EU region (including Norway and Switzerland) in 2030. The relatively low quantity of industrial wood used by the energy sector despite the collapse of the use of coal is explained by the fact that under high CO₂ prices, other energy forms like natural gas, solar and wind energy become more and more competitive. However, the amount of industrial wood used for energy may substantially increase with subsidies for using wood for electricity and heat, even with relatively low carbon prices. With a high coal and gas price and a carbon price of 100 €/t, a subsidy of 30 €/MWh to the wood based and coal with wood co-firing electricity production will have a significant impact on the European wood based sector. Depending on the development of the market demand for forest industry products, such a subsidy may cause a 10–12.5% reduction in forest products production, a 6–9% increase in harvest level, about 30–60% increase in the pulpwood prices, and a 6–9 fold increase of wood imports in the EU, compared to the respective case without a subsidy in 2030.     

The politics of necessity: electricity and water in Great Britain

This paper examines the politics and the policy developments regarding access to electricity and water supply in Britain after the privatisation of these industries in 1990. It does this primarily through discussing two issues: paying for water and fuel poverty. It concludes that, somewhat surprisingly, the introduction of privatisation and greater reliance on market mechanisms has not made the material position of disadvantaged consumers worse as regards these industries. This seems to be attributable partly to changes in the regulatory structure consequent on privatisation and partly due to changes in national politics.     

田间非饱和土壤水分运动的数值模拟──Ⅰ、源汇项及上边界条件的确定

本文通过对野外实测资料的分析计算，用多元非线性回归的方法，拟合了作物根系吸水的数学模型，建立了有作物生长条件下不同生育阶段表土相对蒸发强度Ｅ／Ｅ０与表土含水率θ的经验公式，为进行田间非饱和土壤水分运动的数值模拟奠定了基础。