Microsoft has revealed a 20ft wide by 8ft tall installation that shows if you have enough apples and potatoes you can charge the company's new Lumia 930 smartphone.

On show outside Westfield in Sheperd's Bush, the work, created by Caleb Charland, a science enthusiast and artist, shows that you can charge anything given enough fruit and veg.

Of course Microsoft isn't suggesting you head to the market every time you need more juice [geddit - Ed], but instead opt to charge the new phone either by plugging it into a more traditional power source or via the company's new wireless charging dock, which just so happens to be free at the moment at Carphone warehouse until the end of July.

Caleb’s hand-built circuit of metal, apples and potatoes triggers an electrical current equating to an average of 20mA and 6 volts to power the smartphone.

"Following the success of our lightning experiment that took place in 2013, we were keen to explore another way that we could harness natural energy and charge the brand new Lumia 930 device. We have an obligation to ensure we are always looking for new energy-efficient ways to improve the performance of our products and we’re proud to have done that with wireless charging on the Lumia 930 and some of our other Lumia products," explains Thomas Messett, Head of Digital Marketing and Advocacy for Europe Microsoft Devices on why Microsoft is involved in the installation.

The Lumia 930 was recently reviewed on Pocket-lint. Mike Lowe, our reviews editor had this to say:

"The Lumia 930 is big, bold and has touches of brilliance. As much as it wows, though, there's still work to be done to truly set it apart from the competition. This is one that will divide the crowd, but is a device that can't be ignored for its positives and its aspirations. Whether it can be so highly praised in two months' time from now is another matter, but right now this is the best Windows Phone device that money can buy."

Read our full Lumia 930 review.