These Hong Kong teenagers are on a power trip!

4 schoolboys invent a device to generate electricity from opening and closing doors

HONG KONG: Generating power can be an open-and-shut case: four Hong Kong teenagers have demonstrated this with a prize-winning design for a device that converts mechanical energy from opening and shutting doors into electricity!

The four young men - Ho Wai-tat, Man Chun-wai, Lau Sui-lun and Yiu Kwun-cheun - have invented Electdoor, a handy, gear-driven device that, when affixed to a door, can store the energy channelled from every swing of a door into electricity that can power up home gadgets like doorbells. 

"We reckon that, on an average, everyone in Hong Kong opens or closes a door some 20 times a day," Man told DNA. If all that mechanical energy expended by Hong Kong's 7 million population could be tapped by Electdoor, it would save the power equivalent of some 3,65,000 batteries a year, he reckons. 

Electdoor can be hooked up to the many doors of any home or office, and can help save power. The teens' invention, which was motivated by a desire to create a new form of renewable energy, won them the first prize at a School Science Exhibition in Hong Kong. "We're now looking to make some modifications to improve it; we will then explore the idea of mass-producing the device for the market," Man added. 

But before they do that, the young inventors have to overcome a healthy dose of scepticism from the general public. "Some of the visitors to the exhibition wonder if our idea is practicable - even though we've demonstrated that it is," says Man. "Others say the device is a little clumsy. We'll use their feedback to make improvements in the design, and we'll begin looking for entrepreneurs who can help take our idea to the market."

Hong Kong's Environment Secretary Edward Yau Tang-wah said he would have government engineers examine the practicability of installing Electdoor in government departments. Perhaps reflecting a heightened sensitivity to energy efficiency among today's younger generation, another young team - from the Chinese University's Computer Science Department have devised a "green bicycle".

A sensor attached to the bicycle determines the gradient of the ground; if the rider is riding uphill, the sensor activates a motor that makes it easier to pedal; on a downhill ride, the sensor switches the motor into the charging mode, which ensures that no external source of power is required.