When Min-kyu Choi saw an advert for Apple's swish laptop the MacBook Air, famously marketed as being so thin that it can fit inside an envelope, he realised something was amiss.

The 29-year-old design student from South Korea knew the device would look a lot less sleek after the inclusion of a chunky British three-pin plug. He decided to find a solution, and his resulting invention promises to change the future of consumer electronics.

Mr Choi's design for a folding plug, which at just 1cm thick is less than a quarter of the size of the clunky original, is shortlisted for this year's James Dyson Award, which recognises the world's smartest new inventions. A YouTube video demonstrating how it works has already been viewed hundreds of thousands of times.

"I was on my way to college once and put my laptop in my bag, but when I took it out again there was a huge scratch across the surface which had been made by my plug," said Mr Choi, who moved to the UK eight years ago.

"It was really annoying. A few months later I saw the advert for the MacBook Air, and thought: this is wrong, because people always need to carry the plug too. That's when I had the idea of a really slim one, and started to design it."

Watch the folding plug in action

The gadget formed a key part of his design degree at the Royal College of Art, from which he graduated this summer. He has patented the product and is building a working prototype, which he will seek to manufacture worldwide once it is judged to be safe by the BSI, the UK's safety standards body. But that is unlikely to happen before February next year.

The plug could become the standard power source for laptops and countless other portable electronic devices.

Mr Choi has even created an adaptor allowing three of the plugs to fit into a single three-pin socket.

Essentially a rewired version of a standard plug, in the folding version the live and neutral pins are fixed to a twisting body, allowing them to be rotated from a horizontal to a vertical position when not in use. The earth pin does not move.

A spokesman for the James Dyson Foundation said: "Min's design is a thoughtful, functional and elegant solution to a problem. It goes to show that even the humble three pin plug can be improved upon through creative engineering."

The design of the standard British three-pin plug, known as the BS 1363, has not changed since its introduction in 1947, shortly after the Second World War. It is one of the largest plugs in the world, but is also regarded as one of the safest.

It is still used in many former British colonies around the world, including Cyprus, Malta, Malaysia and Singapore.

Mr Choi is working on several other projects, including a design for a folding suitcase which can collapse for easy storage when not in use.