A concrete-based flywheel energy-storage system will get its first deployment after global wind and solar developer Voltalia signed up for a prototype.

Energiestro’s flywheel design has the potential to be a valuable addition to the storage options for variable renewables said Voltalia, which will install the 10kW/10kWh test system at a site in French Guiana.

Although enjoying far less profile than other storage technologies, various flywheel systems have been developed to tap into the potential of capturing kinetic energy via high-speed rotation for discharge later.

France-based Energiestro uses cheaper concrete instead of steel or carbon fibre in its flywheel technology, which the partners claim offers the additional advantage of not needing specialist materials required for lithium-ion batteries.

According to material on Energiestro’s website, a combination of its flywheels and PV can produce round-the-clock power at €40/MWh ($45/MWh), without giving further details.

Voltalia, also based in France, is one of the most active independent developers and IPPs in global renewables, with almost 2GW of wind and solar built and sold and 1GW under operation.

Voltalia CEO Sébastien Clerc said: "Renewable energy provides without a doubt the cheapest electricity in the world, but it remains intermittent. Using various storage solutions, we can smooth renewable electricity production while offering to the grid a better stability of its frequency.

“After hydro, which remains to date the main storage mode in the world, and batteries, which stand out as a major technology, flywheels can bring a precious complement.”