André Gennesseaux: "I invented a new way to store energy"

For the launch of the fourth annual EDF Pulse Awards, we interviewed previous winners in the Start-up Box.

The concept: the winners answered our questions about their vision for innovation and recorded some words of encouragement for future applicants in the video booth built by the fab lab Draft

Interview with Energiestro co-founder André Gennesseaux, whose work was recognised at the 2015 EDF Pulse Awards.

Find out more about Energiestro

André Gennesseaux co-founded d'Energiestro, a start-up that has developed a new method for storing solar energy. To even out fluctuations in production at a solar power station over a 24-hour period, electricity must be stored overnight. The traditional solution has been to use batteries. The flywheel is one possible alternative. The first is costly, but the second... is as well.

So Energiestro decided to use concrete to create a flywheel with a nearly unlimited lifespan, keeping storage costs low. The flywheel will run for over 20 years, performing more than one million cycles in that time. Batteries, on the other hand, last only a few years and a few thousand cycles. The 'VOSS' (from the French for 'solar storage flywheel') costs around 1 or 2 cents per kilowatt-hour, compared with around 10 cents for batteries.