Australasian Science: Australia's authority on science since 1938

Wave Energy on the Horizon

By Stephen Luntz

Wave power is wind’s neglected sibling, but a CSIRO Wealth from Oceans Flagship report makes clear its capacity to drive Australia’s southern cities.

“Given the potential of ocean energy and the fact that it’s a very new technology, CSIRO wanted to understand what is the sustainable level at which this resource could be used for energy supply and whether it could be competitive with other energy technologies,” says Mr Ian Cresswell, the Flagship’s acting director.

Obstacles to the adoption of wave power are economic and technical rather than physical. The report notes that wave-catching devices along 150 km of Australia’s south coast could meet 10% of its projected 2050 electricity demand.

Intermittency is less of a problem for wave power than solar or wind. The report notes that at Tasmania’s Cape Sorell, low wind conditions exist 42% of the time, but the wave equivalent is just 13%.

Waves are also more predictable. Australia’s southern swells are primarily generated by storms 500–1000 km offshore, making accurate forecasts possible 36 hours in advance, compared with 12 hours for wind. This gives plenty of opportunity for back-up sources to be brought online. Dr Susan Wijffels of CSIRO says that a grid capable of bringing electricity generated at various points along our coastline to markets would also help smooth out variations in supply.

Wijffels says the major obstacle to wave power’s success is finding ways to make energy collection devices last in the punishing marine conditions. Research has lagged on this front, at least until recently.

“Australia is a standout in terms of having huge waves. South Africa and Chile have similar exposure to the Southern Ocean, and some of the countries of northern Europe would have big resources, but the opportunity is not so widespread,” Wijffels says.

Consequently, if Australians want the technology we are probably going to have to invent it ourselves. “Government investment and a premium price for renewables is required for it to get off the ground,” Wijffels says.

Despite these issues, the report concludes that an achievable goal is to generate 10% of Australia’s electricity from waves by 2050. Tidal power only has potential at a few sites, and ocean currents are judged an unlikely medium-term source of power.