Recently, policy makers for electricity industry in the USA and European countries have put their focus on restructuring electricity system to deal with climate change challenges. Further deployment of renewable energy sources, investment in transmission grid to deal with unstable renewable sources, and introduction of “smart grid” are priority issues. Regulators have been exchanging their experiences although still discussion is under way and further development is expected.

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The overseas expansion of power plants project business is growing rapidly recent years. In this big business trend, Electric Power Development (J-POWER) has a big presence as a main player of that field. They have accumulated many projects in many foreign countries including Thailand, United States, etc. And they were also awarded the contract of new coal thermal project in Indonesia. This paper tries to develop the conditions for making strategy to advancing overseas by comparing and analyzing the reasons of successes in each country as case study. These results show that there are three integrants for business planning process.

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The DMIC (Delhi-Mumbai Industrial Corridor) scheme promoted by the Japanese government is an industrial infrastructure development project for India that involves linking industrial parks, ports, and other sites in the six states between Delhi and Mumbai. Industrial parks in India suffer chronic electricity shortages caused by the poor reliability of the commercial electricity supply. This has led companies to install DEGs (diesel engine generators) to provide their own power and avoid having to rely on the commercial electricity grid. Hitachi is working on a system for ensuring a reliable supply of power to the Japanese Industrial Park in the DMIC by applying the concepts of micro grid and smart grid technology and has established a shared energy center with the aim of building up the site's industrial infrastructure. This paper describes the development of a power solution based on the installation of micro grid and smart grid systems at this Industrial Park.

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In the United States, FIDVR (Fault Induced Delayed Voltage Recovery) is one of the main concerns for the stability of power system. The FACTS (Flexible AC Transmission System) can stabilize such phenomena and improve the transmission capability of existing transmission system. This paper introduces the experience of projects for FACTS applications mainly in United States for various purposes including FIDVR mitigation and wind power transmission.

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This paper proposes a new simulation tool for generation expansion planning (GEP) considering variety of uncertainties and investment options. The proposed simulation tool can treat plural uncertainties such as demand growth or fuel price in future, and select adequate investment options such as construction, decommission and reconstruction of generation plant. The proposed simulation tool can also treat the electricity market under the deregulated environment. The influences for several elements - plural uncertainties, investments and competitor's behavior on GEP are discussed through case studies using the proposed simulation tool.

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This paper investigates Japan's long-term energy outlook to 2050 considering massive deployment of solar photovoltaic (PV) system and wind power generation under nuclear energy scenario. The extensive introduction of PV system and wind power system are expected to play an important role in enhancing electricity supply security after Fukushima Nuclear Power Accident which has increased the uncertainty of future additional construction of nuclear power plant in Japan. On these backgrounds, we develop integrated energy assessment model comprised of both econometric energy demand & supply model and optimal power generation mix model. The latter model is able to explicitly analyze the impact of output fluctuation in variable renewable in detailed time resolution at 10 minutes on consecutive 365 days, incorporating the role of stationary battery technology. Simulation results reveal that intermittent fluctuation derived from high penetration level of those renewables is controlled by quick load following operation by natural gas combined cycle power plant, pumped-storage hydro power, stationary battery technology and the output suppression of PV and wind power. The results show as well that massive penetration of the renewables does not necessarily require the comparable scale of stationary battery capacity. Additionally, on the scenario which assumes the decommissioning of nuclear power plants which lifetime are over 40 years, required PV capacity in 2050 amounts to more than double of PV installment potential in both building and abandoned farmland area.

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This paper proposes the optimal total planning for incinerator plants (IPs) in a typical urban area, which includes a method to decide plant number and capacity of IPs. Burnable municipal refuse is disposed sanitarily by high temperature incineration at IPs. At the same time, power generation by waste (PGW) is being conducted at many IPs as recovery of energy. In the present, generation energy of PGW is larger than that of wind power or PV. PGW, however, has weakness of generation efficiency and low generation output due to smaller capacity of IPs. To overcome above weakness, high efficient PGW is necessary with total integration and scaling up of IPs. Regarding total integration and scaling up, the operation in wider area is favorable from the view point of refuse volume and collection. In the planning stage, both cost of IPs and refuse collection which is important for the refuse disposal should be totally taken into account.
The optimal total plan of IPs can be solved at two stages. First, disposal capacity of IP, G_k, for plant number K is decided by constraints. G_k is about the same capacity at each K because of maintenance and refuse collection, and is more than 300(t/d) with every 100(t/d) interval. G_k should be decided by not only refuse volume but also plant stop by maintenance or trouble. Second, cost of each K is calculated by construction/operation cost of IPs, selling energy income of PGW, and refuse collection cost. Therefore K with the minimum cost will be selected as the optimal plant number of IPs.
From numerical simulation of 3 million population's area, the optimal plant number is proved to be four. On the other hand, in the present there are 8 or 9 IPs in 3 million's city. Cost reduction effect above will be about 15% than the present situation. Considering the situation of aging IPs, decrease trend of refuse volume and strict finance condition of local government, the proposal method is very effective and realistic.

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In the direct solution of Y matrix of electric power systems, short circuited branches (ST branches) such circuit breakers and line switches have been generally approximately modeled by small resistances so far. However, when those small resistance elements are included as Y matrix elements, the analytical accuracy is feared due to excessive round-off errors that are caused in factorization process for Y matrix.
A new method of the direct solution of Y matrix including the ST branches is proposed in this paper. As the purpose of factorization is to obtain the node voltages efficiently, the configuration of factored matrix does not need to correspond to that of Y matrix. In the proposed method, the factored matrix is formed in which each ST branch is grouped by same voltage at the connecting ST nodes, and ST nodes except ST retained node are ordered first. Accurate each factored term for these ST nodes which are ordered first can be derived by taking exact zero resistance in conventional factorization procedure. By introducing the new factored terms above, not only the problem of the excessive round-off errors is overcome, but also the sparsity of the factored matrix can be improved.
Demonstrative result is presented for large network model in order to verify the practicability of the proposed method.

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In a future electric power system with high penetration photovoltaic power generation system (PVS), the surplus power may occur during the daytime in the middle season of low electricity demand. Suppressing the PVS power output as well as absorbing the surplus power by using electric storage facilities is one of the measures. By considering the fairness among a number of PVS dispersed in a large area with different insolation level, this study proposes a method to keep the PVS power output at the utility's requested ratio to the available power, and demonstrated the usability of the proposed method by using a simplified experimental setup of PVS. In the proposed method, the operation point on the I-V curve is kept at lower value than the maximum power point (P_PV-X), so that the mean value of PV power during a certain period meets the requested value. P_PV-X is detected without any additional sensor devices by changing the operation point with a certain interval. An experimental test using a test inverter unit demonstrated that the proposed suppression control works well to keep the requested suppression level when the insolation is stable. Two types of control modes, i.e. proposed suppression mode and upper bounded MPPT mode, were applied, so that the proposed suppression control works well for various insolation patterns, which was revealed by using a simulation model of the inverter test unit and the insolation data for a year.

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To achieve higher power supply reliability, it is important to reduce lightning outages. In addition, the cost-benefit of lightning protection methods should be good. Many factors including the causes of lightning surge, the topology and insulation level of the power distribution lines should be considered to establish efficient lightning protection methods for power distribution lines. Furthermore, it is necessary to clarify the flashover characteristics of 6.6-kV power distribution insulators and examine the insulation coordination throughout the power distribution system. This study experimentally clarifies the flashover characteristics of 6.6-kV power distribution insulators currently used by considering polarity differences and pollution conditions.

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In order to evaluate the influence of intensively-installed PV systems on local distribution networks, this letter analyses the spatial correlation characteristics based on multipoint monitored solar irradiation data. As the results, a certain trend of correlation coefficient depending on a distance of separation can be obtained using the solar irradiation data for a month.

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