Green energy system could power home and car

A wireless green energy system being designed by University of Auckland engineering research fellow Duleepa Thrimawithana would harness and integrate renewable energies, such as solar and wind, to power a house and an electric vehicle. The first working model of the concept is being built in the Faculty of Engineering over the next three years.

“Household renewable energy systems need a very large battery to store power, which usually cost tens of thousands of dollars, on top of the cost of installing solar panels or wind turbines,” says Thrimawithana, from the Department of Electrical and Computer Engineering. “The concept here is to use an electric vehicle, which already has a powerful battery, to store some of the power for the system. This would make its installation much more financially viable.”

While such systems may be many years off, the project aims to demonstrate that they can work in practice. The system would make use of emerging technologies in wireless power transfer and intelligent power management. In comparison to existing systems, it would be more cost effective, safer and versatile. Thrimawithana intends to develop new technologies in bidirectional power transfer and new circuitry techniques to improve the efficiency of the system.

Thrimawithana’s project recently won a Foundation for Research, Science and Technology Postdoctoral Fellowship, awarded to New Zealand’s brightest young scientists, funding it for three years.

Thrimawithana says the system could be retrofitted to an existing home or become a feature of new developments. It would draw on renewable energy generated for a single home or a cluster of houses. The system would make use of intelligent technologies, meaning it would automatically schedule charging of the electric vehicle, transfer power back and forth from the grid at optimal pricing and adjust power usage to minimise waste and its carbon footprint. The entire system would be controlled from a central user interface or remotely through the web.

Another distinct feature of the system is the use of wireless or inductive power transfer (IPT) technology, pioneered at The University of Auckland. University researchers have developed several commercial IPT systems and have started looking at applying IPT technology to electric vehicles. The electric vehicle would simply be parked over an IPT charging pad in the garage to transfer energy back and forth.

“IPT is an extremely easy and efficient way to power an electric vehicle and to safely transfer power around a home and back to the national grid, if there is any excess in supply,” Duleepa says. “We know we can’t rely on fossil fuels forever, but current renewable energy technologies cannot meet our energy demands. We have to look for ways to make green energy production viable.”

The concept of a green energy system or ‘ecosystem’, to power both home and transport, was originally proposed by Dr Udaya Madawala from the University’s Faculty of Engineering. A team of students is currently working on various aspects of this system under Dr Madawala and Thrimawithana. Thrimawithana’s aim is to build the first working model of this concept at the university and it is hoped that it will lead to the establishment of the first green energy centre for energy-related research.

Thrimawithana says the concept could open up export opportunities for New Zealand and he has already received significant interest from the industrial and academic communities.