Two important energy savings initiatives based on research undertaken at City University have been put into commercial use over the past 12 months.
Energy saving light dimming technology emerged from a challenge made to Professor Henry Chung Shu-hung, from the University's Department of Electronic Engineering, by the Mayor of Heshan, China. He wanted dimming technology that could be applied to large scale public lighting.
"I had already undertaken work on energy saving lamps. But in Heshan, the Mayor asked me about developing a system for large networks of public lighting, enabling his city to reduce power consumption by 20 per cent across the network," Professor Chung recalls.
He assembled a team that included colleagues and students at CityU. Their goal: to research efficient dimming technology for a range of high intensity discharge (HID) lamps with magnetic ballasts. HID lamps are used in public lighting systems. Although electronic ballasts had been developed for individual lamps, magnetic ballasts were regarded as more reliable, robust and cost effective for street lighting
Twelve months later the group produced the preliminary technology outline. A grant from the RGC resulted in the development of a prototype that produced energy savings of 20 per cent. Further developments led to a system that provided 40 per cent energy savings.
The technology has been transferred to e.Energy Technology Limited, an associated company of CityU Enterprises Limited, and has won product awards in Hong Kong and Australia. It is operating in Hong Kong and China with potential sales this year to Singapore and Australia.
In a separate development, Professor Chung and two students designed an energy efficient burn-in system for switching mode power supplies. This system is based on an energy recovery concept that uses a highly efficient DC/DC converter and grid connected inverter to feed power output