Wave energy, less commonly referred to as tidal, marine or ocean energy, is an emerging technology that uses the limitless power of the ocean to produce zero-emission electricity. As an island nation, Australia is one of the world leaders in the development of wave power. Australia’s south and west coastlines are already home to several wave energy projects as the coasts’ large swells and high ocean winds make it them ideal locations for testing this technology.
Wave Energy is at an exciting stage of its development; It has been endorsed by ARENA and CSIRO as a potential game changer in Australia’s energy industry and some forecasts predict wave energy could contribute 11 percent of Australia’s energy generation by 2050 – enough to power the city of Melbourne.
How does wave energy work?
Wave energy captures the movement of the ocean and converts this into usable electricity. Point Absorber Buoys are the most common wave power generator, however there are numerous other methods currently being experimented with, including oscillating water columns and overtopping devices.
Point Absorber Buoy
These are buoy-like devices which float on or near the water surface and are attached to the seabed by cables. As the waves roll in, the buoy will rise and fall, driving a hydraulic pump to generate electricity. There is a similar device called the Surface Attenuator, which is essentially a row of connected buoys. The rolling waves cause the attenuator to flex, driving the hydraulic pump and generating electricity.
Oscillating Water Column
This device uses an air chamber and turbine to generate electricity. It sits below the ocean surface, and as the waves swell, the pressure will compress the air through the turbine, generating electricity.
An overtopping device is a water reservoir that sits at ocean level. As waves crash into it, the reservoir will fill, suspending water at an elevated level. Once it is adequately filled, the water is released through a series a turbines which generate electricity as it spins.
Carnergie Clean Energy is an ASX listed solar energy, battery storage and wave energy project developer. Carnegie is the 100% owner and developer of the CETO Wave Energy Technology intellectual property (pictured) – a revolutionary point absorber buoy that doesn’t just produce zero-emission electricity, it desalinates water in the process! Carnegie is currently undertaking the largest wave energy project in Australia. In Partnership with ARENA, Carnegie is operating CETO 6 generators, capable of 3 MW of peak generation, off the coast of Garden Island, Western Australia. This electricity is being sold to HMAS Stirling, Australia’s largest naval base.
The future of wave energy
Developing a new energy source is expensive work and we’ve unfortunately seen many promising wave energy companies fail over recent years. Wave Energy may have had a rocky start, but today there are 11 projects and over 200 wave generators along Australia’s coastline. The private sector and government research bodies share a common excitement about wave energy technology, so all signs point toward a bright future for wave energy.