PR facility at the entrance of Miurayama photovoltaic power station in Yamanashi Prefecture Renewable energy is becoming more and more popular. The impact on the power system has gradually emerged. For example, in Japan during the summer (2015), the country’s high-temperature weather continues, but the balance of electricity supply and demand at the peak of electricity consumption has remained relatively stable. Although people's awareness of power-saving has improved somewhat, photovoltaic power generation has indeed contributed a lot to the peak cut in the summer. As the role of renewable energy sources continues to grow, the shortcomings - the effect of fluctuations in output power on the power system cannot be ignored. Without a cheap and high-performance power storage system, output power fluctuations will become a bottleneck, restricting the spread of renewable energy. The Japan Railway Research Institute (hereinafter referred to as "Railway Research Institute") is the project of "Safety, Low Cost, Large-scale Storage System Technology Development" project of NEDO, Japan, and KUBOTEK, Furukawa Electric, and MIRAPRO. Companies such as Japan and Yamanashi Prefecture have jointly developed superconducting flywheels for stabilizing power (see this report). Recently, the pilot test facility for the superconducting flywheel was completed and the ribbon-cutting ceremony was held on September 3. In the future, an empirical test will be conducted on the 1MW photovoltaic panels connected to the photovoltaic power station for the Mitakeyama demonstration test in the Yamanashi prefecture. The superconducting flywheel has a diameter of 2m and a weight of 4 tons and is CFRP (carbon fiber reinforced resin matrix composite). The maximum output power is 300kW and the capacity is 100kWh. This is a power storage system that can release 300 kW of electricity within 20 minutes. In a 1MW PV plant operating at full capacity, even if the output power drops by 30%, power compensation can be given within 20 minutes. The system is not intended for storing energy, and is not intended to be used for the purpose of storing day-time electricity for use at night. A large-scale rechargeable battery with a unit price as low as possible is more suitable for this purpose. The purpose of the flywheel system is to suppress fluctuations in output power caused by cloud changes and the like in a shorter period of time. Although the use of rechargeable batteries can also stabilize output power fluctuations in a short period of time, Railway Research Institute believes that the use of mechanical devices such as flywheels is more appropriate. The reason is that the rechargeable battery accompanying the chemical reaction tends to degrade when it is repeatedly input/output (charge and discharge), and the flywheel is quite stable. In fact, for the case of charging and discharging hundreds of times a day, assuming that the life of the flywheel is 20 years, the number of chargeable/dischargeable times will exceed 1 million. Although the capacity of the power storage system is only 100 kWh, the auxiliary factory building is as large as a tennis court. The flywheel is located in a semi-underground structure and it is estimated that this is due to safety considerations in the event of an accident. 100kWh can be provided by lithium-ion rechargeable batteries for 4 pure electric vehicles, so the initial cost of battery-based power storage systems may be lower. However, battery-based power storage systems may not be used for this purpose without further increase in capacity. In the future, this interest will be verified through empirical tests. There are other uses for high-capacity storage systems that are costly but can tolerate high-frequency input and output, and one of the best uses for railroad regenerative storage systems. In addition, this flywheel is also of great significance as the first application example of high-temperature superconductivity. By using the simple structure of a helium freezer and conduction cooling to locally form a 50K state, superconductivity can be used with less cooling loss, which is of epoch-making significance. The railway research institute also plans to apply this cooling technology to the suspension coils of magnetic levitation trains. (Reporter: Tajima Jin) Power Drill,Drill Bit,Cordless Drill,Electric Drill Wuxi Winsun Automation Instrument Co., Ltd , https://www.winsunwx.com