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The implementation electrolysis plant in combination with wind power plant is proposed, to absorb wind generation otherwise curtailed while generating ‘green’ hydrogen for the merchant hydrogen market. The objective are to (i) achieve exceptionally high wind power penetrations in future power systems, and (ii) derive hydrogen for sale in the existing merchant industrial market from surplus (zero cost) renewable electricity. The economic rationale is investigated for an isolated power system as a function wind penetration, wind curtailment target, electrolyser cost, hydrogen system efficiency and hydrogen sales price. The main outputs are the total annualized cost of wind power plant with electrolysis plant, net annual revenues and discounted pay-back periods. Unprecedented low values of pay-back period are attainable, relative to the implementation of wind power plant at low wind penetrations (ΦW). For example, at ΦW = 50%, a wind curtailment target of 80% allows the investment to be recovered after 4-7 years, provided the hydrogen system efficiency is ≥50% and the hydrogen sales price is 20-30 $/kg. Making use of some non-curtailed wind electricity to boost the utilization of the electrolyser stock is also investigated as a means for improving the return on investment.  相似文献   
2.
Lauri Forsman 《AI & Society》1998,12(4):328-345
Organisations have eagerly adopted the new opportunities provided by distributed computing technology. These opportunities have also created new dependency on the technology and threats of technical problems. Information technology (IT) management has to choose its position towards these new technical risks. Should the problems be prevented proactively in advance or settled reactively afterwards? This paper draws conclusions from an action research case study aimed at proactive versus reactive end-user support. Between 1994 and 1997 one of the business units in Nokia Telecommunications required a new approach for its distributed information systems (IS) to facilitate rapid organisational growth. The distributed IS and its end-user support were established and organised during a 30-month re-engineering process. These results provide a new view to the dependencies between business processes and IT. The new distributed IT has become, often insidiously, a necessity for vital business processes. Therefore, risk management should be adopted as a standard tool for IS management to identify such dependencies. Proactive actions should be aimed at those areas where IT-related business risks are identified. Proactivity should be supplemented by reactive support to provide daily assistance for the end-users.  相似文献   
3.
Nowadays, the use of renewable energy sources is one of the keys to achieve the sustainable development of societies. The intensive use of fossil fuels has caused effects in the environment and the human health. Greenhouse gas emissions and the carcinogenic effect of diesel are widely demonstrated. The production of clean energy based on renewable sources and the use of hydrogen as an energy vector in general and as an alternative fuel in particular represent a technically feasible reality. However, it is necessary to study the economic variables of centralized or distributed production of hydrogen as an alternative fuel. The aim of this paper is to analyze the technical and economic viability of a centralized generation hydrogen plant for mobility use. It was performed a sensitivity analysis of main parameters such as size of hydrogen production plant, operating hours of the plant, investment costs of the main equipment and electricity price. A NPV of 1,272,692 and a 9-year pay-back were obtained for a centralized hydrogen production plant of 2 MW, considering commercial values of the main evaluation parameters. The sensitivity analysis determines that the main variables affecting the NPV are the price of electricity and the operating hours of the plant. With 95% of confidence, the NPV will be positive with an 80.19% of certainty. Therefore, centralized hydrogen production represents a technically viable, environmentally friendly and economically attractive process that can rapidly position hydrogen as an alternative fuel for mobility.  相似文献   
4.
Space heating in cold climates requires large quantities of heat energy to be spent. Therefore, considerable energy-savings can be obtained using construction wall materials with low thermal conductivity in the buildings. In this study, an economic analysis (LCC analysis) was performed in order to estimate the optimum thickness, saving and pay-back period which minimizes the total cost including the masonry material and the energy consumption costs. The LCC analysis was carried out for external walls of buildings in Afyonkarahisar, Turkey. Considering long term and current outdoor air temperature records, degree-days (DD) values were used, and the variation of annual energy requirement of the building was investigated for various masonry (product) types for per unit area. Masonry products were block elements with one, two, three and four row-hollows, hollow-brick and aerated concrete. As the fuel types, fuel-oil, natural gas, coal and electricity were considered in the analysis. The functional unit of the LCC was the use of 1 m2 of the building's living area over 50 year's period. As a conclusion, the highest energy-saving was obtained by the use of hollow blocks with 4 rows. Moreover, the most suitable fuels for all climate zones appear to be electricity and fuel-oil. But, the natural gas is a better choice when the atmospheric pollution is an important consideration.  相似文献   
5.
Energy conservation by using energy efficient electric motors   总被引:1,自引:0,他引:1  
Mehmet Akbaba 《Applied Energy》1999,64(1-4):149-158
This paper deals with energy conservation by installing energy-efficient (EE) motors instead of standard efficiency motors. This transition become a necessity as a direct result of limitation in energy sources and escalating energy prices. As electric motors use about three quarters of the total electric energy in Bahrain, attempts to conserve the energy consumed by electric motors recently received intensive research efforts. Therefore, the energy efficiencies of energy efficient motors are compared with those of standard efficiency motors ranging from 5 to 300 HP. To provide more clarification in this regard, full design details of 200 HP standard-efficiency and energy-efficient motors are compared. Pay back periods when replacing standard-efficiency motors with energy-efficient motors, with reference to Bahrain's market, have been discussed. Finally the energy-conservation capability of EE motors in the petrochemical industry has been discussed.  相似文献   
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