Storing solar energy in graphite

February 10, 2008

Canberra Times: Once a supply depot and airstrip for the mighty Snowy Mountains Hydro-electricity Scheme, Polo Flat, east of Cooma, is now headquarters for a new energy enterprise for rural Australia. When the scheme was completed, some of its engineers formed the Snowy Mountains Engineering Corporation, now known as SMEC, a worldwide engineering and development consultancy.

About seven years ago, a group within SMEC began developing Australian scientist Bob Lloyd’s invention for storing thermal energy in purified graphite. It was decided the best way to test and commercialise the technology was to form a separate company with an agreement that SMEC would provide all the engineering services. A group of investors formed Lloyd Energy Systems, which now has a laboratory, workshop, heat-storage blocks and a graphite-cleaning pilot plant at Polo Flat. Now an accredited research agency, the site also has demonstration storage plants, a wind-to-heat demonstration and a small-scale commercial plant incorporating water treatment, storage and steam turbine generation.

Lloyd Energy’s chief executive, Steve Hollis, said the past six years had been spent testing the storage of solar energy at very high temperatures and preparing the technology for market. The research has generated strong interest, culminating last year in a $5million Federal Government grant for an advanced energy storage program in the western NSW town of Lake Cargelligo. Country Energy will take the power for its grid network in a project worth $10million.

Lloyd Energy also has an agreement with Ergon Energy in Queensland to build a $30million plant, three times larger than Lake Cargelligo’s, and has a $7million contribution from the Queensland Government. Mr Hollis said large amounts of coal-fired energy were lost during long transmission to remote areas.

As power loads built up over time, mainly because of demand for air-conditioners, the grid could no longer cope in peak periods. Towns at the end of the line suffered the most from power shortages. “We’re putting environmentally friendly generation out at the end of the branches of the tree if you like, so it can pump energy back in when the branches are in trouble,” he said.

“It actually serves three purposes. Firstly, it is a renewable energy replacement for coal. Secondly, it avoids the country energy authorities having to upgrade their transmission lines so they can get more power out in the peak.” The third benefit was having an energy source at the end of the line that could return power into the grid.

“This is a modular system,” Mr Hollis said. “We have made it modular so it can be redeployed in remote rural locations in rural Australia and overseas, without involving monstrous towers….