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Hitachi ’ s Adjustable-speed Pumped-storage System Contributing to Prevention of Global Warming
| Content Provider | Semantic Scholar |
|---|---|
| Author | Nagura, Osamu Higuchi, Mikisuke Tani, Kiyohito Oyake, Takashi |
| Copyright Year | 2010 |
| Abstract | INTRODUCTION PUMPED-storage power plants were first constructed and operated in the early 1900s as a supply and demand balancing mechanism that worked on a time scale of hours by storing excess power during the night so that it could be supplied back during the daytime demand peak. The “adjustable-speed pumped-storage generation system” developed by The Kansai Electric Power Co., Inc. and Hitachi incorporates a function (activepower-based control) that can control the power level in both pumping and generation modes with a faster response time than existing pumped-storage power plant systems. This feature allows the adjustable-speed pumpedstorage generation system to share the burden of balancing supply and demand during the night when demand is low that is normally handled mainly by thermal power generation, and this in turn helps shorten the operating time for thermal power generation and reduce CO2 (carbon dioxide) emissions. The Okawachi Power Plant of The Kansai Electric Power has two adjustable-speed pumped-storage generation systems which were manufactured by Hitachi, have the largest capacity of any such systems in the world, and have been operating reliably for over 15 years. It is also anticipated that the proportion of the power supply provided by renewable energy sources such as wind and solar power will increase significantly in the future. Incorporating energy sources such as wind and solar power from which it is difficult to obtain a steady power output into the electricity grid will reduce the relative proportion of thermal, hydro, and other conventional power sources and this is likely to make balancing supply and demand even more difficult. This has the potential to become a major impediment to providing a stable electricity supply. OVERVIEW: To help prevent global warming, it is anticipated that renewable sources of electric power will provide an increasing proportion of energy needs. Because energy sources such as wind and solar power are dependent on weather conditions, their output can vary widely. Usually, balancing supply and demand for power has been performed by adjusting the generation output in response to varying load, but there is a need to improve the supply and demand balancing functions of existing generation systems to allow the addition of generation capacity produced from renewable energy sources. Hitachi has developed a world-first adjustable-speed pumped-storage generation system that incorporates active-power-based control to provide a power supply and demand balancing function that can operate on time scales from the order of seconds to the order of hours, something that is not possible with conventional systems. It is anticipated that the addition of a large number of adjustable-speed pumped-storage generation systems to the electricity grid will help prevent global warming. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.hitachi.com/rev/pdf/2010/r2010_03_107.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
