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UK’s ‘greenest energy supplier’ to reignite Musk rivalry with home storage launch

Dale Vince: "The Black Box… it's not black and it's not a box." Image: Ecotricity.
The UK’s “greenest electricity supplier” will launch trial units of its own residential energy storage system this year, with the potential to reignite an ongoing and acrimonious rivalry with Tesla.

Ecotricity, based in the south west of England, primarily generates and sells energy from 70MW of wind turbines that the company owns and operates. Company founder and CEO Dale Vince spoke with Liam Stoker of our UK sister site Solar Power Portal last week.

Vince said that a residential energy storage system aimed at the British market, first announced in May last year under the working name of “The Black Box”, is now being readied for launch but had undergone a few revisions since the concept was first conceived. Vince said Ecotricity’s work behind the scenes on energy storage had been ongoing for some time.

“We dreamt up the idea about five years ago, we call it ‘The Black Box’ – it's not black and it's not a box – and we should be putting the first units into trial this summer,” Vince said, stating that it had been in R&D “for some time”.

Vince was discussing his company’s purchase of recently bankrupt SunEdison’s rooftop solar business in the UK for the Solar Power Portal site when he spoke about the storage units. Vince described rooftop solar as the “missing piece” of his business, before going on to discuss the storage system. While he was not able to give many further details as yet, Vince said the devices were designed to benefit the network as well as the individual system user or owner.

“It's basically a load shifting device, we spent a lot of time studying the grid and what the best size device would be to shift domestic load on and off the grid at different times of the day… our device is quite special, and we'll be unveiling details of it probably in a few months' time,” Vince said.    

Rivals dispute 'greenest' claims

The company recently hit headlines when Tesla, for reasons unknown, decided to contest Ecotricity’s claim to be the UK’s greenest provider of power.

Britain’s Advertising Standards Agency (ASA) watchdog however refused on 6 April to uphold Tesla’s complaint. The US EV and stationary storage maker had said Ecotricity claims to supply the “greenest energy” in Britain were untrue. Subsequent to that ruling, Good Energy, a UK rival supplier, also chose to challenge Ecotricity’s position.

Tesla and Ecotricity in fact had previous form in this area – the two parties settled out of court last year after a deal to build a network of EV charger stations turned sour. An accidentally misdirected email in May reportedly showed that Tesla was trying to cut Ecotricity out of the agreement and build partnerships with roadside services providers without the green power supplier. At the time UK national newspapers reported that the email – which said Tesla wanted to encourage service stations to break off existing agreements with Ecotricity – was accidentally sent to an Ecotricity employee.

Additional reporting by Liam Stoker.

Solar Media's Energy Storage Summit takes place this Thursday, 28th April, at Twickenham Rubgy Stadium, London. The event - featuring 40 high-level speakers and three streams (residential, commercial and utility scale) - will address all the key issues related to storage deployment. 

Ecotricity EV charger on a UK motorway, complete with the company's distinctive "green Union Jack" flag emblem. Image: Andy Colthorpe.

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