Sun in Canberra? Enough to make heat AND power!

The world's largest combined solar hot water and electricity system is coming to the Australian National University in Canberra.

The solar concentrator system, designed and built by the Centre for Sustainable Energy Systems (CSES), will provide both solar electricity and solar hot water for residents of the University's soon-to-be-built extension of Bruce Hall.

Sun-tracking parabolic glass mirrors concentrate sunlight by about 30 times onto the receivers mounted about 700 mm above the mirrors. On the undersurface of the receivers are mounted efficient solar cells that convert about 20% of the reflected sunlight into electricity.

The remaining 80% of the light is converted to heat, which is collected by water flowing in a channel behind the solar cells.

This Combined Heat and Power Solar (CHAPS) System represents a technological breakthrough in solar energy production. While photovoltaic solar power systems and solar power hot water systems have each been around for decades, until now the two have not been combined in the one unit due to differences in technologies.

A CHAPS-style concentrator system has three significant advantages over a conventional flat-plate solar system. The area of the roof space needed for the solar collector is substantially reduced; most of the high-cost solar cells are substituted with cheaper mirror material; and the system tracks the sun, giving better utilisation of morning and evening sunshine.

Item provided courtesy of The Austalian National University