Storing battery-tier volumes of energy in spinning flywheels sounds terrifying on scale - a cursory search indicates 1kWh ~ 1 KG of TNT.
I guess it depends on the risk of an exploding flywheel, but batteries seem likely to fail in a much less explosive manner as opposed to a failed flywheel.
I guess it depends on the risk of an exploding flywheel, but batteries seem likely to fail in a much less explosive manner as opposed to a failed flywheel.