A renewable energy company is celebrating after clinching a deal to fit solar-powered batteries made by the manufacturers of the Tesla high performance electric cars.

According to Denbigh-based Hafod Renewables, the technology is going to provide a shot in the arm to the solar power industry because it stores up energy that would otherwise be wasted.

The firm has been approved by Tesla, one of the biggest names in green technology, to supply and fit their Powerwall wall-mounted batteries which cost from £3,000.

The batteries which are approximately five feet high, three feet wide and just eight inches deep, weigh just over 200 pounds and can be fitted to an exterior wall and linked to roof-mounted solar panels.

David Jones, Managing Director of Hafod Renewables, said: “The big advantage of these batteries is that the electricity generated by solar power during the daytime can now be stored and used in the evening when you need it.

“Previously that electricity would have been sold straight to the National Grid which has become a less attractive option as the Government has cut the feed-in tariffs which were paid.

“But for a homeowner being able to use the electricity generated by solar panels later in the evening can mean massive savings.”

The average annual electricity bill is between £700 and £800 and David reckons using a home battery can cut that by £500 or more.

One of the first fitted has been at the home of retired agricultural contractor Philip Johnson, in Erw Salisbury, Denbigh, where it’s already making its presence felt.

Mr Johnson said: “I went for solar panels and solar hot water and now I’ve had the battery installed and it’s a really good saver.

“Today is freezing cold but the sun’s out and the battery is charged and I’m actually sending electricity to the grid.

“The battery will power the house through the night until early tomorrow morning and it’s only costing me about 30p a day to run the house.”

Tesla Chief Executive Elon Musk, one of the leaders of renewable energy worldwide, believes his firm will will soon be selling more house-powering batteries than electric cars.

David’s father, Richard Jones, Director at Hafod Renewables, said: “We’re thrilled to be associated with the world-leading electric car company Tesla.

“There are other batteries on the market but the 10-year no-quibble guarantee on the Tesla Kit is unrivalled.”

Hafod Renewables, based on Denbigh’s Colomendy Industrial Estate, was founded six years ago by David, an electrician and graduate in Renewable Energy and Richard, a heating engineer, when the solar industry, fuelled by a generous feed-in tariff, was booming.

A Government cut to that tariff has driven many firms out of the business but Hafod, which employs six staff, has continued to grow as the company has expanded into other areas such as ground source heat pumps and underfloor heating.

In those six years – Hafod Renewables installed their first system in July 2010 – they have fitted over 10,000 solar panels, stacked end on end they would tower over 29,028 foot Mount Everest.

Most of their clients have been domestic solar systems but they have also installed solar power on farms, businesses including one of Wales’s biggest boatyards, a rugby club and even on a secondary school as well as providing biomass boilers and air and ground-source heating systems.

David Jones said: “The new batteries are very advanced pieces of kit which can even be fitted to older properties and to those with existing solar systems.

“They can be installed with the capacity to automatically switch over and run a home’s electrical systems in the event of a power cut which would put an end to hunting around in the dark looking for candles, matches and torches.

“They are extremely sophisticated pieces of equipment and the price starts at just under £3,000 so that the average home can have a solar system and battery installed for between £9,000 and £10,000.

“Under the old system the feed-in tariff could generate you £2,000 a year but since the cut that’s been slashed to £250 so the most cost effective way of using solar is with a battery because the power you generate in daylight is then available to power your home when you need it.”

He estimates that from November to the end of February, when days are shortest, a conventional south-facing solar system with a battery would still generate part of a home’s required power while for the remaining eight months it would virtually power the home completely and even be able to sell any excess to the grid.

Hafod Renewables also offer a finance deal for their systems and the battery could pay for itself in six years while it can also be fitted to charge from the mains off-peak when power is cheapest – just 6p per kilowatt hour compared to 15p per Kwh at other times.