Flexible flywheel offers cheap energy storage
Low loss and low cost
Mechanical engineering isn't within the scope of Vulture South, so we'll welcome readers' input about whether this is genius or snake-oil: a Kickstarter project called the Velkess Flywheel hopes to offer low-cost energy storage.
Flywheels are good at storing energy, but building them to fine mechanical specifications can get expensive. The Velkess proposal is to use a flexible flywheel that deforms in response to mechanical stresses, rather than trying to overcome the engineering challenges of making rigid flywheels reliably and cheaply enough to act as off-grid energy stores.
The Velkess Flywheel's proposal is to use the cheap and common “E-glass” fibreglass as the rotating mass – something which the project's Bill Gray says has already been demonstrated at small scale, here.
Gray says the current prototype can store 0.5 kWh of energy. To act as a serious storage unit for off-grid power applications – replacing lead acid batteries for remote solar or wind installations – Gray wants to get the storage up to 15 kWh.
To do that, he says, the project needs to create a 750-pound (340 kg) flywheel to replace the current 25-pound (11kg) unit, and create a magnetic motor and bearing assembly that can handle the heavy flywheel.
The project's current Kickstarter is to design a brushless DC motor or generator that can run in a vacuum (reducing the friction losses to around 2 per cent per day, Gray hopes). ®