ARRA（２） GRIDS

ARRA(American Recovery and Reinvestment Act of 2009)のなかで、エネルギーは重要な位置を占めます。エネルギー関係のプロジェクトを統括するのは、米エネルギー省（DOE）の関連機関であるAdvanced Research Projects Agency-Energy(ARPA-E：エネルギー先端研究計画局）ですが、エネルギー関連の重点プロジェクトをさらに幾つかのカテゴリーに分けています。
そのうち、グリッド（電力網）のそれぞれの場所での再生可能エネルギーを用いた電力の貯蔵を目標にしたのが「Grid-Scale Rampable Intermittent Dispatchable Storage (GRIDS)」です。昨日のフライホイール蓄電や、各種の新しい電池や、圧縮空気蓄電の案件もこのカテゴリーになります。ARPA-Eのサイトに記載されているこのGRIDSの説明は下記の通り。

ARPA-E seeks to develop new technologies that enable widespread use of cost-effective grid-scale energy storage. While valuable applications for grid-scale storage exist, this program focuses on technologies that balance the short-duration variability in renewable generation. Investing in these technologies will position the U.S. as technology and manufacturing leader of the emerging, and potentially massive, global market for stationary electricity storage infrastructure. GRIDS seeks to develop revolutionary modular storage systems that provide the energy, cost, and lifecycle of pumped hydropower, and can be widely implemented across the power grid. Specifically, GRIDS considers two areas: 1) proof–of-concept storage-component projects focused on validating new, over-the-horizon, electrical energy storage concepts, and 2) advanced system prototypes that address critical shortcomings of existing grid-scale energy storage technologies. Ultimately, technologies developed through this program will be scalable to megawatt and megawatt-hour levels of power and energy capacity. GRIDS will complement other DOE grid-scale energy storage efforts by focusing on technology prototyping and proof-of-concept research and development, rather than pilot demonstration projects.

実際の再生可能エネルギーを用いた発電・蓄電プラントの建設とかには、数百〜千億円規模の政府による債務保証(Loan Guarantee)と数億円規模の補助金(Grant)によって支援されます。
たとえば、アリゾナ州に蓄電設備を備えたconcentrating solar power (CSP)発電所を作ろうとしている「Abengoa Solar Inc.社」に下記の様な支援が決定されました。この発電所は７万世帯に電力供給可能で、６時間分の電力を溜めることもできます。なお、７００Ｆは３７１Ｃです．

Of that, a $1.45 billion loan guarantee has been extended to Abengoa Solar Inc. to finance the construction and start-up of a concentrating solar power (CSP) generating facility in Solana, Arizona. The technology will use parabolic shaped glass mirrors that direct sunlight onto receiver tubes that heat the fluid inside to over 700 degrees Fahrenheit. The heat is then used to turn steam turbines. The project also includes a thermal energy storage system that will allow for the production of electricity after the sun has set.
The first of its kind in the country and one of the largest CSP plants in the world, the project will supply clean electric power to approximately 70,000 homes and will add 250 megawatts of capacity to the electrical grid using the parabolic trough solar collectors and a six-hour thermal energy storage system. Electricity from the project will be sold through a long-term power purchase agreement with Arizona Public Service Company.

by 阪口