Tesla Energy has announced its new home battery system called the Powerwall.

The Tesla Powerwall battery, which can be placed at homes or in businesses, stores solar energy. The idea is to make people less reliant on the power grid as well as offering a back up should that fail.

What's new about that?

Solar storage batteries already exist but Tesla says they are difficult and complicated to install and use. It's lithium-ion offering comes as a single unit or in multiples for those who need more power.

Powerwall wants to empower users via several different routes. Firstly, it will store excess energy produced from your own solar generation, so that energy not used at the time will be available later. In addition, it can store power when electricity from the power grid is at its cheapest rate, off-peak. This can be used during peak hours to lower costs in the household it is installed.

The aim it two-fold: to save you money long-term (accepting the initial outlay), but in a wider context, combined with solar power generation, reduce reliance on the power grid and shift your energy to a green source.

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Tesla

Tesla says it wants to ease the world into a greener future: "Once we're able to rely on renewable energy sources for our power consumption, the top 50 per cent of the dirtiest power generation resources could retire early. We would have a cleaner, smaller, and more resilient energy grid."

What can Powerwall run?

Tesla says the Powerwall Home Battery is able to juice up everything in your house. From a 0.2kWh fridge to a 2.3kWh washing machine, the 7kWh or 10kWh Powerwalls should be able to keep you running.

For those that know their electricity consumption numbers, the Powerwall offers continuous power at 2kW with a peak power output of 3kW.

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Tesla

The limit isn't on batteries either as a double battery configuration, or more, is possible. Of course you will be limited by the amount of sunlight filling the batteries, but as Powerwall is integrated with the power grid, when you're not running off your own energy, you just revert to regular mains supply.

How much is Powerwall and when can I get it?

The Tesla Powerwall is $3,500 for 10kWh or $3,000 for 7kWh to suppliers with deliveries beginning in late September. This works out at about £2,285 or £2,000 respectively, but there's no word on it shipping to the UK. That's the cost to suppliers, however, so there will then be plenty of costs on top, like installation, as well as the solar panels you'll need to capture energy from the sun.

Friends of the Earth's renewable energy campaigner Alasdair Cameron told the BBC: ""Cheaper and more efficient energy storage means individuals and businesses could save renewable energy until they need it, hugely reducing the need for climate-changing fossil fuels."

Tesla has so far names Treehouse, SolarEdge and Green Mountain Power as channel partners for Powerwall. 

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