Solar power tower: way of the future or expensive gimmick?

‘Concentrated solar power’ (CSP) – better known as solar towers – are solar panels’ seemingly unsuccessful cousin. The tall towers had immense promise, but in most cases were plagued with technical problems or expenses.

But a new generation of researchers are trying to get CSP to work. This is because CSP does have one advantage over solar panels: a huge built-in battery.

CSPs have several different designs, but all of them start with large numbers of mirrors all shining sunlight up to a tower or receiver. Sunlight heats mineral salts in the tower to 560 degrees Celsius, and then the heat is funnelled into a ‘heat exchange’ which boils water. At this point the steam drives a turbine, while a storage tank holds the heat for later use.

In the latest issue of Cosmos Magazine, science journalist Rachel Williamson looks at the numerous CSP projects throughout Australia, and travels to northern Victoria to visit a solar and energy storage pilot called RayGen. The system is the newest generation of CSPs, with solutions to earlier problems and a promise to be cheaper, more efficient, and with less leaking molten mineral salts.

RayGen’s bringing a new generation of hopes, but Australia’s CSP history is littered with failed attempts.

Cosmos Magazine #97 is available now at all good newsagents or subscribe at comosmagazine.com and save up to $35.