The flywheel is an old technology that dates back to Neolithic-era spindles and potter’s wheels. Flywheels made a huge splash during the Industrial Revolution (anyone remember steam engines?) and now they’re ready to take center stage in the new wave of sustainable energy.
In sustainable energy, flywheels come into play as a means of storing intermittent power. Wind power and solar power are notoriously fickle in many parts of the world, and some means of smoothing out the bumps is required. Vycon is one of several companies exploring the potential of flywheels, and it has come up with some interesting twists.
What a Flywheel Does
If you’ve ever played tether-ball, the idea behind a flywheel is simple. You provide sharp bursts of intermittent energy to send the ball around the pole. The weight of the rope and its course around the pole combine to even out those bursts, creating a relatively constant, steady motion. The rope also stores energy; after it is fully wrapped around the pole, the ball reverses course at a relatively steady pace, without any more help from you. A similar principle applies to potter’s wheels, which can be kept in steady motion with intermittent kicks.
What a Flywheel Is
Companies like Vycon have ramped up this simple principle into sophisticated flywheel energy storage systems. Vycon’s proprietary system consists of a steel hub with magnetic bearings, a dual motor/generator (the motor charges the system, the generator dispenses the energy), high tech system controls, and a converter that transforms the flywheel’s AC power into DC.
Flywheels can be used to store energy from solar and wind installations, and Vycon has come up with a couple of other applications that it calls “energy recycling.” The company has developed a flywheel system for harvesting the energy that normally is dissipated when large shipping cranes are lowered. In a similar vein, Vycon has also developed a flywheel system that can harvest and store the braking energy from commuter and freight trains. Both the crane and rail applications could become an important contribution to the management of carbon emissions from global shipping, especially in sensitive coastal areas.
Flywheels in Action
Flywheel technology could also be used to harvest energy from mining operations, or from elevators in buildings. Compared to sustainable energy storage solutions such as molten salt, flywheels may also be more portable and site-adaptable. They are also highly durable and they are already starting to pop up in some high stress environments. A couple of years ago, Formula 1 cars started to phase in a flywheel/hybrid electric system called Kinetic Energy Recovery, which stores waste energy in a flywheel instead of a battery. The newly online Ross Island Wind Farm in Antarctica is expected to make a huge dent in the base’s carbon footprint with the help of a flywheel storage system.
Image: Flywheel from an old factory by Rajesh Dhawan on wikimedia commons.
Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. You can also follow her on Twitter @TinaMCasey and Google+.