Beacon Power Flywheel Frequency Regulation Plant to Buffer 20MW on Grid

November 12, 2009

Beacon Power will begin construction on the nation’s first full-scale 20-megawatt (MW) flywheel frequency regulation plant during the week of November 23rd, at its site in Stephentown, New York.

All state and local construction-related permits and approvals for the plant have now been received. Beacon will start initial site work while continuing to progress toward closing a $43-million loan with the Federal Finance Bank, with the support of the U.S. Department of Energy and a loan guarantee commitment that Beacon received earlier this year. The loan is intended to support construction of the plant.

“We’re extremely pleased to be breaking ground on our first 20-megawatt flywheel plant this month,” said Bill Capp, Beacon president and CEO. “Thanks to the support of a number of agencies, organizations and individuals, including the Federal Energy Regulatory Commission, Department of Energy, New York ISO, the New York State Energy Research and Development Authority and the Public Service Commission, as well as local officials in Stephentown, we can now move forward with construction.”

A Clean and Innovative Use of Energy Storage

Frequency regulation is an essential grid service that is performed by maintaining a tight balance between electricity supply and demand. Beacon’s 20 MW plant has been designed to provide frequency regulation services by absorbing electricity from the grid when there is too much, and storing it as kinetic energy in a matrix of flywheel systems. When there is not enough power to meet demand, the flywheels then inject it back into the grid, thus helping maintain proper electricity frequency (i.e., 60 cycles/second). Thanks to its ability to recycle electricity efficiently and act like a “shock absorber” to the grid, the flywheel plant will help also support the integration of greater amounts of intermittent wind and solar power resources. However, unlike conventional fossil fuel-powered generators that provide frequency regulation, Beacon’s plant will not consume any fuel, nor will it directly produce CO2 greenhouse gas emissions or other air pollutants such as NOX or SO2.

Flywheel energy storage works by accelerating a cylindrical assembly called a rotor (flywheel) to a very high speed and maintaining the energy in the system as rotational energy. The energy is converted back by slowing down the flywheel. The flywheel system itself is a kinetic, or mechanical battery, spinning at very high speeds to store energy that is instantly available when needed.

At the core of Beacon's flywheel is a carbon-fiber composite rim, supported by a metal hub and shaft and with a motor/generator mounted on the shaft. Together the rim, hub, shaft and motor/generator assembly form the rotor. When charging (or absorbing) energy, the flywheel's motor acts like a load and draws power from the grid to accelerate the rotor to a higher speed. When discharging, the motor is switched into generator mode, and the inertial energy of the rotor drives the generator which, in turn, creates electricity that is then injected back into the grid. Multiple flywheels may be connected together to provide various megawatt-level power capacities. Performance is measured in energy units - kilowatt-hours (kWh) or megawatt-hours (MwH), indicating the amount of power available over a given period of time.

Beacon's Smart Energy 25 flywheel has a high-performance rotor assembly that is sealed in a vacuum chamber and spins between 8,000 and 16,000 rpm. At 16,000 rpm the flywheel can store and deliver 25 kWh of extractable energy. At 16,000 rpm, the surface speed of the rim would be approximately Mach 2 - or about 1500 mph - if it were operated in normal atmosphere. At that speed the rim must be enclosed in a high vacuum to reduce friction and energy losses. To reduce losses even further, the rotor is levitated with a combination of permanent magnets and an electromagnetic bearing.

Beacon Power's grid-scale Smart Energy Matrix is made up of multiple integrated systems of (10) Smart Energy 25 flywheels, interconnected in an array, or matrix, to provide energy storage for certain utility applications. The Smart Energy Matrix can absorb and deliver megawatts of power for minutes, providing highly responsive frequency regulation capabilities for increased grid reliability.

A Word About Sustainability and Energy Storage

Sustainability is a philosophy and set of practices that have gained considerable acceptance among global organizations in recent years. The concept of sustainability refers to business conduct that addresses the economic, social and environmental impacts of operations; the so-called "triple bottom line." More than 50% of Fortune 100 companies have adopted sustainable business practices and issue comprehensive annual progress reports. These companies, including many in the energy sector, are taking a longer-term view that considers the total impact of a product or service, from development through end-of-life.

Flywheel-based energy storage systems, unlike fossil-fuel power plants that are used on the grid for frequency regulation, are sustainable "green" technology solutions that consume no fossil fuel, nor produce CO2 or other emissions during operation. Further, Beacon's flywheels operate reliably for many years with little or no maintenance, making them a true sustainable technology solution.