The US Department of Energy (DOE) has finalized a $43-million loan guarantee for Beacon Power Corporation’s 20 megawatt innovative flywheel energy storage plant in Stephentown, NY.

Beacon’s Gen 4 flywheel system is specifically designed to perform frequency regulation on utility grids by absorbing and discharging energy to balance power generation and consumption on the electric grid. The technology operates by using flywheels to quickly store and release from the grid in order to follow rapid changes in grid demand.

Flywheel-based regulation is fast and efficient, ramping up or down 10 times faster than ramp rates for conventional fossil fuel generators that typically perform this service.

Beacon estimates that a 20 megawatt flywheel-based frequency regulation plant will reduce carbon dioxide emissions up to 82% over its 20-year life compared to a coal, gas or pumped hydro plant. The flywheel plant also does not emit air pollutants such as nitrogen dioxide or sulfur dioxide.

This is the second loan guarantee announced that will provide significant improvements to New York state’s electrical grid. Last week DOE offered a $17.1 million conditional commitment to AES Storage for a project based in Johnson City. (Earlier post.)