Simply solar: Around the Blocks

Canberra Times
Thursday 23/11/2006 Page: 6

SOLAR efficient houses were not only comfortable to live in, they presented huge benefits for the environment as they ran on sustainable energy, an Australian National University academic said yesterday.

Dr Keith Lovegrove, of the Centre for Sustainable Energy Systems, said one common application of solar energy for a home was the solar hot water system. It used a black metal plate and a standard hot water tank. Water flowed in and out of the tank and was heated for free ensuring big savings, particularly in an all-electric home, as one of the biggest uses of electricity was the hot water system, he said.

If designed properly, a home won't need any other sources of energy at all," Lovegrove said.

A solar passive llonie would need a lot of insulation and plenty of north-facing windows. He cited about three quarters of a north-facing wall to be ideally made of glass, however this could become too hot, so a lot of thermal mass, such as concrete, must be included.

For the summer, there must be shading on all windows, with appropriate eaves. There was the need for ventilation at night and with the existing thermal mass, there should be no need for cooling in the sunnier, Lovegrove said. Another benefit would be that a solar passive home would be more comfortable than electric heating or cooling in a badly insulated home, he said.

The construction of such a home need not be any more difficult than the construction of a conventional house. Lovegrove said there would need to be a rise in demand so enough builders would be compelled to supply such homes.

People who would like to retrofit their houses for more solar efficiency could add insulation to their walls, ceilings and floors. The windows and curtains could also be improved. Double glazed windows were an option and a solar hot water system could be installed and would attract a rebate.

Lovegrove suggested green electricity for people who would like to make their homes even more eco-friendly. It costs more than conventional electricity, but it would cone from green sources, such as wind farms.

If all Australians adopted this technology for their homes, it would remove the need for at least two coal-powered stations, he estimated. For every kilowatt of electricity, a kilogram of carbon dioxide is released into the atmosphere. Every kilogram saved is a kilogram less in the atmosphere," lie said.

"There is proven technology today that means we could have a 100 per cent renewable energy-powered economy. It is technically possible. This includes transport, street electricity and home electricity.

Renewable energy is the world's fastest growing industry, mainly to do with large wind turbines." Examples of solar efficient homes in Canberra included 11 and 13 Ronia Mitchell Crescent, Majura Rise Estate, North Watson.

Together with local businesses, ACTEW Corporation, Actew AGL and Canberra Investment Corporation created the homes.

Number 13 was made of concrete and had a good thermal mass. It also had solar chimneys, full-height doors, solar panels, solar hot water and a water-recycling system from Canberra company Perpetual Water. The gardens were landscaped and drought sensitive.