Flywheel2
A little known fact is that NASA has a flywheel program. The international Space Station (ISS) is periodically in the Earth’s shadow, so that its solar arrays do not work all of the time. A form of energy storage is required in order to operate the ISS while eclipsed and during peak loads. At one time, NASA had considered using flywheels to store electrical energy on the space station. Like many other NASA programs, the flywheel program has seen better days, but the technology still exists. Much of the research had centered around Glenn Research Center.
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