[The Vector] Xcel Energy Tests Wind-to-Battery Storage

Xcel Energy, a Midwestern electric and natural gas company, released its preliminary test results in early August 2010 on its wind-to-battery storage technology. After one and a half years of testing, the preliminary results are a success, it says.

Luverne, MN, serves as the test center with the battery installation connected to an 11 MW wind farm owned by Minwind Energy, LLC.  The twenty 50 KW battery modules are about the size of two semi trailers, weigh about 80 tons and can store about 7.2 MW-hours of electricity. Fully charged, the battery modules could power 500 homes for more than seven hours, said Xcel Energy on August 3, 2010.
Xcel Energy revealed the following in the preliminary report:

• The battery can effectively shift wind energy from off-peak to on-peak availability.
• The battery can reduce the need to compensate for the limited predictability of wind generation.
• The battery can support the transmission grid system by providing reliability and voltage support.
• The battery can support regional electricity markets by responding to real-time imbalances between generation and load.

Frank Novachek, director of corporate planning for Xcel Energy said on MRP Radio news, “We are increasing our ownership in wind ourselves, and so we’re wanting to look at what the value might be in using a battery as an integral part of the wind farm to shape the output of the wind farm directly. We wanted to test it because we have interests in using storage to help us with grid stabilization for customers.”The tests in Luverne showed 75 percent efficiency with the battery. Excel Energy says that the results indicate the technology could be applied to solar energy as well. Phase II testing will continue to determine the ability to facilitate larger penetrations of wind energy on the grid and various battery system functions. A final report on the study is expected in the summer of 2011.

For certain renewable energies to be adapted, the question of energy storage must be addressed. The sun does not always shine, the wind does not always blow, and consumers have to be assured of constant energy availability. Battery storage, such as in these tests, storage through hydrogen and even in salt, are all being tested for future use and development. Bravo, Xcel.