But instead of relying on those electric pumps, Carnegie is using the latest iteration of its CETO technology — CETO 5 — to supply that pressure with wave energy instead. Underwater buoys eleven meters in diameter are installed offshore, and as ocean waves catch them, the movement supplies hydraulic power to pump seawater up underground pipes to shore. At that point, the water runs into the desalination plant, where it directly supplies the pressure for the reverse osmosis. Some of that hydraulic energy is also converted into electric power as needed.
The two megawatt demonstration project will be situated on Garden Island, near the coastal city of Perth in Western Australia, and will ultimately supply roughly 55 billion litres of drinking water per year. A previous desalination plant set up by Water Corporation in Kwinana, south of Perth, already supplies 45 billion litres. The final total of 100 billion litres a year is half the city’s drinking water needs.
Southwestern Australia has been especially hard hit by droughts, and unaffected by the reprieve from the dry period the rest of the continent has enjoyed. And climate change models project that the traditional freshwater supplies for Perth will dry up even further by 2030. Meanwhile, Australia as a whole has been suffering the ravages of climate change, what with record-setting heat waves, floods, and other extreme weather. So anything that could provide the country freshwater without adding anymore to the globe’s carbon emissions is a welcome development.