In typical Gadget Buffet fashion we appear to be behind the Times in reporting the advanced technology being used to secure the future of sustainable energy. Over a year since Tesla Motors (an electric car maker) unveiled a range of comparatively low-cost batteries capable of powering homes and businesses,  we are now hearing plans that could revolutionise the energy market.

Elon Musk, the chief executive of Tesla Motors, announced the company would build batteries that store solar energy in what he described as the “missing piece” in the transition to a sustainable energy world.

The wall-mountable lithium-ion batteries are designed to capture and store up to 10kWh of energy from a wind or solar panel with reserves drawn when sunlight is low, during grid outages, or at peak demand times, when electricity costs are highest. An average British home uses around a third of the battery’s charge capacity in a day.

Mr Musk said the device – known as the “Powerwall” – would allow consumers to harness energy independently rather than rely on a power grid.

The technology, which is predicted to slash energy bills, could provide enough electricity to meet the world’s needs, the billionaire technology entrepreneur claims.

Mr Musk, speaking during a launch event at a Tesla facility in California, described the batteries, which come in two sizes – a 7kWh model ($3,000 or £1,970) and a 10kWh version ($3,500/£2,300) as a “fundamental transformation [in] how energy is delivered across the earth”.

The pricing of the Powerwall managed to surprise Tesla’s critics. At $3,500 for 10kWh or $350 (£230) per kWh, not including installation, the device is far cheaper than experts predicted.

Tesla Reveals the Powerwall from Tesla Motors on Vimeo.

Trip Chowdhry, an investment analyst, previously estimated the price of a 10kWh battery might be about $13,000 (£8,500) while another industry expert, Sam Jaffe, predicted a running cost of between $500 (£327) and $1,000 (£655) per kWh including an inverter.

It is essential that a Powerwall is fitted by Tesla Certified Installers

The smallest Powerwall is 1.3m by 68cm, small enough to be hung inside a garage or on an outside wall. Up to eight batteries can be stacked in a home. It is essential that a Powerwall is fitted by Tesla Certified Installers – a local search on Yell revealed very few in the UK at present.


Tesla Energy Powerwall Certified InstallerImage Source: SWDART

Mr Musk explained to investors and journalists, that the units had the ability to be “a critical step in this mission to enable zero emission power generation”.

“With Tesla Energy, Tesla is amplifying its efforts to accelerate the move away from fossil fuels to a sustainable energy future with Tesla batteries,” he said, “enabling homes, business, and utilities to store sustainable and renewable energy to manage power demand, provide back-up power and increase grid resilience.”

Mr Musk also stressed the portability of the new technology. “You don’t need a battery room … A normal household can mount this on their garage or the outside wall of their house and it doesn’t take up any room. It’s flat against the wall,” he said. “It’s designed to work with solar system out of the box.”

The batteries will initially be built at the electric car company’s factory in California, but will transfer production to its planned “gigafactory” in Nevada when it opens in 2017.

The Nevada facility will be the largest producer of lithium-ion batteries in the world, in a move that the company hopes will further drive down costs.

Powerwall is not the only battery storage system on the market, but it benefits from a relatively high storage capacity, a competitive pricing and the excitement surrounding Mr Musk’s investment.

The CEO estimated that changing global transportation, electricity generation and heating to renewable energy, primarily solar, would require about two billion of his Powerpack batteries, the model designed for business-level usage.

He explained: “That may seem like an insane number. But this is actually within the power of humanity to do.”

There are about 2 billion cars and lorries on the road globally, while another 100 million vehicles are made yearly, according to Mr Musk’s estimates.

He added: “We have done things like this before. It’s not impossible.”

For remote locations, Mr Musk said he expected the kind of disruption that followed the advance of mobile phones for people who lived in areas without landline telecommunications coverage.

At one point, he noted the press conference was being powered by Tesla’s batteries and solar power, without using grid power.

Deutsche Bank estimates sales of battery storage systems for homes and businesses could yield as much as $4.5bn (£2.94bn) in revenue for Tesla. The energy storage industry is expected to grow to $19bn (£12.4bn) by 2017, according to the research firm IHS CERA.

Tesla is taking orders for the systems, with the first units expected to be ready in August.

Colin Langan at UBS, speaking before the launch, said he was cautious about the overall outlook. “Getting battery cost down is key, but on the stationary storage side there are a lot of questions about which chemistry will dominate long term. It might not be lithium,” he said.