The Guardian reported that Australian solar companies are working on a large scale thermal projects believe that they are close to achieving the dream of building energy plants that are big enough to replace coal-fired energy in the country.
Experts speaking at the Australian Solar Energy Exhibition and Conference in Melbourne have stated that the technology was already proven in other countries and projects in Australia were viable. Although the projects are promising, getting major investors to gamble on something new is still a big challenge. According to James Fisher, chief technology officer of Vast Solar, solar thermal energy, had been considered the “poor cousin” of the photovoltaic solar panels for some years, but it may be finally changing.
The concept behind large-scale solar thermal is quite simple, although building it is not. Curved mirrors called “heliostats” are positioned in a field, then reflects the sun’s energy onto a tower with a receiver on top. A liquid material, usually molten salt is pumped through the receiver and heated, it is then pumped back down to be stored in a tank. The hot liquid is used to heat water, creating steam to power turbines producing electricity when needed.
Vast Solar has a solar thermal plan in Jemalong, near Forbes, 320 km west of Sydney and will complete a 6MW pilot plant within the next few months. The project then will move forward with 30MW plant on the site which would be a commercial-scale plant which will also be a proving ground for vast Solar’s technology. Vast Solar’s project uses 27-meter towers and each tower have a receiver in front of hundreds of heliostats. The solar pumps liquid sodium into its receivers where it is heated to about 600C before it is pumped back down where the heat is transferred to molten salt for storage. The company has already raised $25M for the project so far and is enough to go on with the 30MW power station.
(Image credit: Braxton Walls)