A CHATSWOOD car park will be the site of the biggest council-owned solar farm in Australia. Willoughby Council has commissioned Solgen Energy to install 140 solar panels across the roof of its six-storey Albert Avenue car park, leased to Westfield.

The project is the first part of a three-year plan to build a 300-kilowatt energy system that will provide power directly to three council-owned buildings.

The council's director of sustainability projects, Sally Hamilton, said the $4 million project would pay for itself in energy savings over the 25-year life of the solar panels. Energy generated by the rooftop system will be diverted into the main council office, a childcare centre and a community centre.

The Solgen founder, Joe Coco, said the rooftop solar farm was the first of its kind in Sydney. ''It's an ideal use of space, and a model that's being used in America, where there are lots of large car park rooftops next to huge malls … it could take off here as well.''

In response to a complaint by residents about the potential for glare, the NSW government architect's office conducted a reflection analysis which found residents in surrounding high-rise apartment blocks would be exposed to ''very minimal'' reflected glare twice a day, for up to 15 minutes each time.

Solgen said it had opted to use a new glazing technology that would reflect less sunlight.

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