Can Beacon Power patent the idea of using flywheel technology for frequency regulation? Apparently the answer is yes, at least according to Beacon’s press release.
“Beacon Power invented the idea of using high-energy flywheels to regulate grid frequency, so it’s appropriate that we’ve now been awarded a core patent for the idea,” said Bill Capp, Beacon president and CEO. “The patent gives Beacon exclusive rights to this innovative method of providing an essential grid service, and further strengthens our intellectual property position.”
The patent is U.S. Patent No. 8,008,804, “Frequency Regulation Using Flywheels.”
Beacon has certainly developed a great deal of control and grid integration technology to enable their flywheels to supply ancillary services in regional power grids. For some background see, for example, this 2010 paper from Beacon that describes flywheel system performance in an 18 month field trial in the ISO New England system. A paper from 2004 presents Beacon’s analysis of the benefits of using flywheels for grid frequency regulation instead of using hydro or fossil-fueled generation.
Still, I don’t see how they can claim to have invented the idea of using flywheels to supply frequency regulation services. Especially given the prior use of flywheel systems to provide grid frequency regulation service, as described in this paper published in 2000 describing a 1996 commercial installation of a flywheel on the Okinawa Electric Power Company transmission grid in Japan.
The 2000 article, which refers to the flywheel system as ROTES (ROTary Energy Storage system), reports:
This is the world’s first commercial operation of such a large capacity flywheel energy storage system… When the ROTES was disconnected from the 66kV bus, frequency fluctuation of over +/- o.4 Hz often appeared in the line frequency, resulting from sudden load changes as large as 30 MW. When the ROTES was connected, the frequency fluctuation was suppressed within +/- 0.3 Hz, thus meeting the goal of installation. The ROTES has been operating properly for more than two year, showing great promise as a FACTS device which has the capability of releasing or absorbing electric power with a response time as fast as less than 100 ms.
(HT to correspondent/former colleague/occasional reader MH for tipping me off to the press release and useful dialog.)
UPDATE: A commenter from Beacon helpfully provides a link to the patent, http://bit.ly/nMupPp, and notes that the above article was specifically considered by the patent examiner as part of the patent application review.