The lead investor was Energy Technology Ventures, a joint venture of General Electric, utility NRG Energy, and fuel company ConocoPhillips. Another investment group involved was Aster Capital, which represents transportation and power companies Alstom, Schneider Electric, and Rhodia.
Like batteries, ultracapacitors store energy but they have different properties that make them well suited for certain applications, such as powering motors for electric windows in a car or to adjust the pitch of wind turbine blades.
Ultracapacitors can discharge a lot of power in quick bursts, but can't store as much overall energy as batteries. They also can be charged very quickly and last for many charge cycles. Improvements in performance and more familiarity among industrial designers are nudging the technology into different areas...
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