Integrated Plan and Evaluation of Distributed Energy Systems Taking into Consideration Renewable Resources

学生名:任　洪波
研究テーマ:English
(日本語)
入学年月:2006.03
修了年月:2009.03
取得学位:博士（工学）
論文概要:After decades of power generating units increasing in size, there is currently a growing focus on distributed power generation close to energy loads. Investments in large-scale units have been driven by economy of scale, but recent technological improvements on small generating plants have made it possible to exploit the benefits of local power generation to a larger extent than previously. On-site distributed energy systems, including combined heat and power (CHP) systems and renewables, such as photovoltaic (PV) and wind turbine have grown more important and are widely expected to spread to increase the efficiency of energy consumption and to address global environmental problems. Additional benefit may be gained from distributed systems through clusters of distributed energy resources (DER) and loads in the same geographic area. Usually, distributed energy applications prefer natural gas technologies due to the wide spread of gas network and the potential of relatively low air emissions. As a result, the engine technology has been driven by economic and environmental pressures for power-density improvements, increased fuel efficiency and reduced emissions. However, recently, as the introduction of clean energy sources, renewable distributed generations have played an increasingly important role in potential energy production. Usually, renewable resources are used in rural areas without grid generation. In the past few years, as the promotion of some new policies, such as net metering, and the development of storage technology, renewable distributed generations have been spread widely in urban districts. In Japan, a country that depends on imports for most of its primary energy supply, the government is taking all kinds of measures to save energy and develop new energies. The Ministry of Economy, Trade and Industry (METI) laid down a new Long-Term Energy Supply and Demand Outlook to 2030 and an interim report was released in June 2004. In the report, a distributed generation development scenario was proposed, which suggested that the share of distributed on-site generation in total electricity supply would exceed 20% by 2030 [1]. Distributed energy system offers end-users increased flexibility in provision of energy as they can generate on-site or purchase from the utilities. However, it will also result in more complex systems to design, operate and management as it introduces physical connections between traditionally separate supply sectors. Therefore, the increasing appeal of distributed generation means that there is a need for new tools to analyze and evaluate distributed generation, both from a system perspective and from the perspective of potential developers. In this thesis, firstly, the method for planning and evaluating distributed energy system is analyzed theoretically. By studying previous researches, new plan and evaluation tools are developed. Focusing on the value of power generation for end-users, this thesis identifies how an end-user can find optimal distributed energy systems and investment strategies under a variety of economic and regulatory scenarios. In addition, the optimal operation strategies corresponding to the variations in energy demands are discussed.