研究故事

A new technology that uses electric springs to store and transmit energy overcomes a key barrier to the widespread use of renewable energy.

The promise of renewable energies, be they wind, solar or other sources, has excited governments around the world. Some have set targets to have up to 40 per cent of electricity provided by renewables (Hong Kong’s is one to two per cent). But these ambitions ignore a major obstacle: it is still very difficult to integrate unstable renewable energy into the power grid.

The ‘smart grid’ is meant to solve the problem of instability by using modern technology to manage the different inputs to the grid. But it is not yet a reality and scientists from around the world, including HKU, have been trying to figure out how to make it work.

“The challenge,” says Professor Ron Hui, Philip KH Wong Wilson KL Wong Professor in Electrical Engineering, “is that in the existing system, power companies can fully control power generation and flow. They can control the voltage according to how much electricity power a city requires, and transmit that power in a centralised, reliable manner.”

“In the future the system will change drastically. With renewable energy, you and I can put up solar panels, a farmer could set up a wind farm, and the power company won’t know how much power is being generated. Having all these sources with dynamically changing natures means power companies lose control. When the supply and demand can’t match up, you have instability.”

"What we want to do is to utilise something that we drink every day that would be good for your health and oral hygiene."

Dr Ricky Wong

Professor Ron Hui (left) and Dr Lee Chi-kwan (right) working together on the Smart Energy Lab at Imperial College London

The full version of this article was originally published in Bulletin. Please click here to view this HKU publication.