A new deal: get a substantial discount on Powervault 3 systems (4 or 8kWh) but you give over use of your battery to EDF energy who can do what they like in exchange. Sounds like a bad deal TM. This is the offer sent to us via email by Jack Peck at Powervault. So this reduces cost of e.g. 8kWh system from £7k to £5k. But then you are basically paying EDF for their capacity and this does not seem to be a good idea. Plus EDF are building nuclear power stations which we do not approve of.