Key Energy has installed a three-phase flywheel energy storage system at a residence east of Perth, Western Australia. The 8 kW/32 kWh system was installed over two days in an above-ground enclosure, dramatically cutting the time needed to install the flywheel system.
Quite correct. Even if the outer casing is enough to contain the rotor, that is still 32 kilowatt hours of kinetic energy that goes somewhere. They’re saying they saved money by putting it above ground, that means if potentially the casing fails you have little shards of metal going out with great energy in every direction.