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181.
Lee Schipper 《Energy and Buildings》1984,6(1):15-38
We describe energy use in Swedish homes from 1963 to 1980 using data assembled and analyzed for the first time. Changes in energy use by fuel and purpose before and after the 1973 oil price shock are illustrated and discussed, and savings in space heating in the year 1980, compared with the pre-embargo period, are quantified. We discuss two important elements of Swedish energy conservation policy, the building codes and the system of grants and loans to homeowners. We conclude that the grants and loans probably accelerated home retrofit measures, while the building codes will play an important role in reducing residential heat losses over the long term. 相似文献
182.
过临猗县闫家庄镇陈庄果园试点,对用涌泉灌、滴灌及微喷灌三种微灌技术进行比较,结果表明涌泉灌具有抗堵塞能力强、投资少、管理方便、使用寿命长等优点,应予优先推广 相似文献
183.
The objective of this study is to introduce one of the main results of the project for studying energy conservation technologies in a new airport town, which is organized by the Osaka Science and Technology Center, Japan. First, based on the estimated energy demands in the new town, technological aspects are investigated for the district heating, cooling and hot water supply system. Then, the economic and energy saving characteristics are compared for several alternative systems according to the differences of the type of absorption refrigerating machine and so forth. Assuming that a combined heat and power plant is used as the heat source plant of the district thermal distribution system, the optimal combined district heating, cooling and power generation system has been selected from a comprehensive economic viewpoint. Lastly, it is ascertained that if fuel costs continue to rise at the rate of 8 per cent per year, the best energy conservation system becomes superior economically to the conventional district thermal distribution system. 相似文献
184.
应用模糊集合理论建立了灌区工程老化损坏程度综台评判模型。该模型在我省44处大中型灌区中进行了计算,根据计算成果对所评定的灌区工程进行了老化损坏程度排序及等级划分。 相似文献
185.
186.
本文结合县级水资源开发利用现状分析工作实际,论述有关农业灌溉需水量、可供水量和供需平衡的计算,举出实例阐明某些重要基本概念。 相似文献
187.
阳离子聚合物正电胶泥浆研究与应用 总被引:2,自引:1,他引:1
根据正电胶MMH对储层损害小,MMH-粘土结构具有强触变性的特点,把正电胶MMH引入阳离子聚合物泥浆,组成了阳离子聚合物正电胶泥浆,成功地解决了塔里木盆地塔中地区井壁坍塌问题,也取得了保护油气层的效果。 相似文献
188.
189.
The primary purposes of this paper are to describe a practical model which can be used to assist economic evaluation of district heating proposals, with particular reference to potential micro combined heat and power (CHP) applications, and to discuss the results of applying this model to a proposal for a particular scheme. The problems of realistic simulation of demand patterns, and the sensitivity of micro-CHP project values to scale, fuel prices, differential purchase/selling tariffs for electricity, duty cycle and plant utilization factors are discussed. Of several options, two were shown to be economically viable, relative to existing methods of supply (gas-fired boilers); however, the margin of benefit is small relative to wisely chosen modern boiler installations. A brief discussion of alternative methods of finance is provided; ceteris paribus, the proposed scheme would not be likely to attract venture capital from would-be lease-hire agencies. There is scope however for pilot schemes, whose results could be used to define more closely the limits of uncertainty of, for example, annual availability and duty cycle influences on the cost economics of operations. 相似文献
190.
The Kerava solar village is the first regional building complex in Finland with a combined solar heating and heat pump system using seasonal heat storage. The village will be completed at the beginning of 1983. In this study we describe the heating system of Kerava solar village. The heat demand was estimated by computer simulations. Different weather conditions and operational situations were considered. Under normal weather and operating conditions approximately 60 percent of the total heat demand of the Kerava solar village is estimated to be obtained from solar energy. 相似文献