Smart grid unlocks renewable power

New technology jointly developed in Hong Kong set to unleash potential of sustainable energy

PUBLISHED : Thursday, 10 January, 2013, 12:00am
UPDATED : Thursday, 10 January, 2013, 4:34am

The use of renewable energy sources could be more substantial after a breakthrough invention was found to stabilise the voltage of power systems with a renewable power supply.

The invention - Electric Springs - is a new smart grid device which applies the compression and extension principles of springs to counter the fluctuating voltages of renewable power.

In other words, when the voltage decreases, the Electric Springs will perform a boosting function and vice versa to maintain the voltage stability of a given power grid.

Power supplies of renewable energy sources - such as solar and wind - are highly intermittent due to natural weather conditions.

The principles of mechanical springs were first introduced by a British scientist Sir Robert Hooke in 1660 but were never applied to the electrical field.

"It is amazing how a 300-year-old law has laid down the foundation for smart power grids in the 21st century," said Ron Hui Shu-yuen, chair of power electronics at the Department of Electrical and Electronic Engineering at the University of Hong Kong.

While some European countries have set a target of having up to 20 per cent of their overall power supply created by renewable energy, the aim has been restricted by the intermittent nature of this resource.

With the invention of Electric Springs, which are to be embedded in electric appliances within the household, the intermittent problem can be overcome without risking damage to some appliances which are susceptible to voltage fluctuation.

"We believe it is possible that this invention will impact the whole world," said Hui, who leads the joint research team of the University of Hong Kong and Imperial College London.

The proportion of renewable power supplied to an existing national grid could rise to as much as 40 per cent in the future.

After being initially granted HK$5 million in funding by the Research Grant Council, the team is expected to apply for further funds to build infrastructure to test the invention in the South China Sea, Hui said.