Wave energy for Perth southern desalination plant?

Australian wave-energy developer Carnegie Wave Energy Ltd (CWE) announced on 5 July 2012 that it had been advised by West Australia’s Water Corporation that it wished to move forward on discussions for up to 2MW of renewable energy supply for the Southern Seawater Desalination Plant on an exclusive basis.

The arrangement could be long‑term or short‑term depending on a satisfactory commercial deal for Water Corporation.

The seawater reverse‑osmosis plant is already committed to purchasing renewable energy from the Greenough River solar farm and the Mumbida wind farm. A provision in these agreements accommodates supply by CWE.

Carnegie has previously announced alternative power offtake options for its Perth Wave Energy Project including the Australian Department of Defence. A decision on the final power supply arrangements for that project is expected shortly.

The CETO system has an array of fully submerged buoys tethered to seabed pump units. The buoys move in harmony with the motion of the passing waves, driving the pumps which in turn pressurise water that is delivered ashore via a pipeline.

On shore, high‑pressure water is used to drive hydroelectric turbines, generating zero‑emission electricity. The high‑pressure water can also be used to supply a reverse‑osmosis desalination plant, replacing electrically driven pumps.