Can flywheel energy storage make money

Additionally, flywheels are capable of many charge/discharge cycles per day (compared to many other energy storage technologies) without any degradation of performance over time, and they can provide ancillary services like frequency regulation, offering grid operators more value from an energy storage device.

The strategic locating of storage capacity and multi-cycle capability of flywheels can save millions of dollars in transmission congestion costs. There are even larger savings to ratepayers due to the deferral of transmission and distribution system upgrades.

It would probably have to be in a cement enclosure, and in Florida a sump pump to keep it dry. A 1,000kg, 5m, 200RPM flywheel would store 685,567J of energy if it was shaped like a disc. That's 0.19kWh of energy — enough to boil the water for about seven (7) cups of tea or run a typical airconditioner for about 10 minutes.

Flywheel storage basically consists of a flywheel that is accelerated to very high speeds and suspended in a vacuum, energy is stored in the form of rotary motion that can be extracted by decelerating the flywheel. With recent advancements, yields of around 80% have been achieved which is the highest compared to any other storage device.

The total energy content or storage capacity of a flywheel is 864 Wh (NEDC) and 416 Wh (FTP 75). The effective flywheel storage capacity, which refers to the range of the energy content in the flywheel between the minimum and maximum value, is 648 Wh (NEDC) and 312 Wh (FTP 75).

Flywheel batteries are probably the most compact energy storage systems that can be designed with the lowest environmental impact and highest durability. Not quite domestic, but the technology keeps maturing. It's better suited for leveling short-lived and massive power needs rather than storing energy for days (note the 7%/hr loss below).