Tesla now powering homes

Tesla Motors has announced what could be the holy grail when it comes to sustainable, self-sufficient energy for both your car and house – and it could be available to Australians next year.

Powering your electric car for free with renewable energy has long been an automotive utopia for many, who insist that electric cars merely shift the CO2 footprint from exhaust outlets to coal-fired power stations, especially in countries like Australia.

The theory goes that if everybody drove an EV powered by the sun or the wind – at least as their primary car for the daily commute – they could travel for free without ever emitting the planet-warming CO2 generated by non-renewable fossil fuels.

But because solar panels only generate power while the sun shines and when the wind blows, the hurdle for both domestic and automotive power self-sufficiency is the storage of energy for later use, which requires expensive batteries that currently cost tens of thousands of dollars.

Now Tesla, the Californian start-up car-maker that rewrote the rulebooks for electric cars, says it has the answer with its Powerwall Home Battery, an affordable energy storage unit that can power your house with renewable energy and potentially allow households to go off-grid and avoid power blackouts.

And the best news is that Tesla says it will be available in the US by August, and in the Asia Pacific region (including Australia) as early as next year – before Europe.

The Tesla Powerwall comprises a rechargeable lithium-ion battery, liquid thermal control system and software that receives dispatch commands from a solar inverter. It mounts seamlessly on internal or external walls and is integrated with the local grid to harness excess power and give customers the flexibility to draw energy from their own reserve.

Tesla says the Powerwall's ability to store energy at a residential level brings a number of different benefits to the customer, including load shifting, in which it provides financial savings to its owner by charging during low rate periods when demand for electricity is lower and discharging during more expensive rate periods when electricity demand is higher.

It will also increase self-consumption of solar power generation because the battery can store surplus solar energy not used at the time it is generated and use that energy later when the sun is not shining, and can act as a back-up power source, assuring power in the event of an outage.

Tesla says the Powerwall is compatible with a growing list of inverters, offers 2kW of continuous power and peak power of 3kW, delivers 'round trip efficiency' of more than 92 per cent, has an operating range of -20C to 43C, measures 1300mm wide, 860mm deep and 180mm high, and comes with a 10- or 20-year warranty.

The best news is price. Tesla says it will sell the Powerwall to installers for $US3500 ($A4435) for the 10kWh version, which it says is optimised for back-up applications, or $US3000 ($A3800) for the 7kWh version.

"The 10kWh Powerwall is optimised to provide back-up when the grid goes down, providing power for your home when you need it most. When paired with solar power, the 7kWh Powerwall can be used in daily cycling to extend the environmental and cost benefits of solar into the night when sunlight is unavailable.

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

To help retail the system, Tesla has partnered with US sustainable home improvement store TreeHouse, whose co-founder and president Jason Ballard said: “For the first time, running your home on a battery will be affordable and easy.

“I think in the near future, having a battery in your home will be as normal as having a water heater or a dishwasher. This just takes us one step closer to being able to power homes completely without the use of fossil fuels.”