Tesla Powerwall 3 home battery now on sale in Britain – what is it and can it really save you big on energy bills?

Tesla has launched its Powerwall 3 home battery in the UK – but how does it work, and can it really save you £1,450 a year on your energy bills?

The Tesla Powerwall is a large rechargeable battery that mounts to the wall of a home, and the third edition of the battery is now available for sale.

The Powerwall can store electricity for use at a later point, with households able to use the device to save money on their energy bills.

This is everything you need to know about how the Tesla Powerwall 3 works.

How does a Powerwall 3 work?

The Powerwall lets households store solar-powered electricity, either through solar power or for use with time-of-use energy tariffs.

These tariffs are special energy deals that charge less for electricity used in off-peak periods – often at night.

Homes with a large battery fitted, such as the Powerwall, can take advantage of this by charging up when electricity is cheap, then using that power when electricity is more expensive.

Another perk of the Powerwall is that it automatically detects power cuts and kicks in.

When extreme weather is forecast, the Powerwall 3 will charge to its maximum. That energy can then be used to power household appliances in the case of a power cut.

The device can still work when submerged in 60cm of water, and in temperatures from -20c to 50c.

How much electricity can a Powerwall 3 store?

The Powerwall 3 can store up to 13.5kWh of electricity when new Tesla says, falling to 9.45kWh after 10 years.

The average home uses around 7.3kWh of electricity a day, according to energy regulator Ofgem, meaning one Powerwall should comfortably be able to power most homes on a full charge.

However, more than one Powerwall can be fitted for homes with very high electricity needs.

Part of the background: The Powerwall can be fitted to the exterior of most properties

How much does it cost?

The typical cost is £6,300 for one Powerwall 3.

This is made up of £5,500 for one Powerwall and another £800 for the Tesla Gateway, which allows energy metering and management and the ability for the Powerwall to kick in during a powercut.

But the overall cost will vary, and customers can get more accurate quotes on the Tesla website.

Crucially, the prices above do not include installation costs or VAT, meaning the price to fit one Powerwall is likely to be in the £7,000 to £8,000 region.

How much can it save me on my energy bills?

Tesla claims the Powerwall 3 can save the average home £1,450 a year on their energy bills.

That is a significant saving, as the typical home currently pays £1,690 a year for energy, falling to £1,568 a year from 1 July.

That means a home with a Powerwall could spend just £118 on energy bills a year from 1 July.

However, to achieve the £1,450 saving a home would need to have solar panels installed.

Customers also need to factor the installation costs of the Powerwall.

A £7,000 bill to fit the Powerwall would mean a cost of £700 per year for the typical home, which reduces Tesla’s claimed savings to around £750 a year at current energy prices.