Beacon Power Corp. Flywheels to Help New York Grid Stability

Load control strategies and concepts:
– Stability
– Frequency regulation
– Voltage regulation
– Load leveling
– Power quality

FastCompany
Large scale power storage can be extremely helpful for maintaining a stable power grid. One of the important load control strategies is "frequency regulation." Grid controllers can maintain the power frequency of the grid within acceptable limits by absorbing or releasing a portion of the supply energy to the grid, as needed.

To ensure a functional and reliable grid, the Independent System Operators (ISOs) that operate the various regional grids must maintain their electric frequency very close to 60 hertz (Hz), or cycles per second (50 Hz in Europe and elsewhere). When the supply of electricity exactly matches the demand (or "load"), grid frequency is held at a stable level. Grid operators, therefore, seek to continuously balance electricity supply with load to maintain the proper frequency. They do this by directing about one percent of total generation capacity to increase or decrease its power output in response to frequency deviations.

...Over the last decade, Beacon Power, in conjunction with the U.S. Department of Energy (DOE), California Energy Commission (CEC), the New York State Energy Research and Development Authority (NYSERDA), and various ISOs, has developed an advanced flywheel-based energy storage technology to perform fast-response frequency regulation. _Beacon

The US DOE has finalised a $43 million loan guarantee to Beacon Power Corporation for installation of a 20 MW flywheel storage system in Stephentown, New York, for purposes of frequency regulation of the power grid.

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. _GCC

Flywheel storage has extremely low energy density, which prevents flywheels from being effective for other purposes of grid stabilisation such as significant load leveling. And in terms of emergency power backup, flywheels are only effective for a very short period of time, before backup gas generators or other backup can be brought on line.

List at top excerpted from: Load Control System Reliability presentation

This development is being touted as a means to reduce CO2 exhaust, but in reality this effect is not even a drop in a bucket. The continued improvement of high-tech flywheels is one important component of a total power grid and emergency power backup picture, however. A very small part, but an important part nonetheless.