Physics & Engineering

Elon Musk unveils battery to take your home off-grid

Elon Musk's Powerwall battery, to the left. Photo credit:
Elon Musk’s Powerwall battery, to the left. Photo credit:

After much anticipation, South African-born entrepreneur Elon Musk has finally unveiled a battery designed to help homes go off-grid and run using solar power. Adam Oxford from has the story.

Musk’s Tesla Motors firm announced Powerwall this morning, a lithium-ion battery which is built to be charged from solar panels. It’s gird-tied, which means its output can be augmented with mains electricity if your demand peaks and comes in two flavours.

The first is a 10kWh box, which our back of the envelope calculations reckon would keen a home going through a full cycle of loadshedding, and the second has 7kWh capacity. You can order them – if you live in the US – and they cost $3 500 (R41 600) and $3 000 (R35 700) respectively.

Our initial thoughts are that that’s not much cheaper than current tech in terms of rand per kWh of storage (most commercially available batteries are rated for amp hours rather than kilowatt hours), but when you factor in the control systems is good value for money. Plus, Tesla says it’s made the system as easy to install and use as possible. Plug and play, if you’ll pardon the pun.

Like all good devices in the internet of things, it connects to your home network for monitoring and data collection.

According to Musk, Powerwall has been in testing for over a year. The image below gives you a better idea of its size than the pic above.

One of the most remarkable things about Powerwall is that, like Tesla’s intellectual property for electric vehicles, Musk says that the patents for Powerwall will be open to allow others to innovate around the tech. That could have interesting implications for South Africans involved in similar areas, like Pretoria’s Netsheild SA.

How quickly can someone use Powerwall tech to build a loadshedding-busting box here? We’ll be catching up with local experts as soon as possible.

Thanks to our friends at for this story.

EXTRA: Watch what Musk had to say about it at the launch function.

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