NPQ proposes to use wave power technology to desalinate seawater and generate electricity for residential and commercial use. In conjunction with wind and solar energy technology, NPQ hopes to harness these renewable energy sources to make reliance on fossil fuel energy unnecessary.
Wave energy is a renewable energy and is a zero emission source of power. As water is about 800 times denser than air, the energy density of waves exceeds that of wind many times over. This dramatically increases the amount of energy available for harvesting. Waves are predictable days in advance, making it easy to match supply and demand.
The world has been waiting for the first commercial-scale wave or tidal plant to function successfully. Several companies now believe they have cracked the problem in using the vast energy that is generated by the movement of the seas and oceans.
One patented technology now available, named after the Greek ocean goddess Ceto, uses a fully submerged pumping technology with the power generated onshore using standard hydro-electric turbines to generate the electricity. The technology was devised in the 1970s by Carnegie Corporation's chairman Alan Burns. It was only in 1998, however, that serious work began on developing the technology.
The system has no visual impact because it is moored underwater. The units operate in deep water, away from breaking waves. The waves regenerate once they pass the units, meaning there is no impact on popular surfing or swimming beaches.
The units are designed to operate in harmony with the waves rather than attempting to resist them. This means there is no need for massive steel and concrete structures to be built.
Ceto wave energy technology produces fresh water directly from seawater by magnifying the pressure variations in ocean waves. Any combination of power and water can be achieved from 100% power to 100% water. The system uses no oils, lubricants or offshore electrical components - it is built from components with a known sub-sea life of over 30 years. The units also act like artificial reefs in the way they attract marine life.
Submerged buoys are moved up and down by the ocean swell, driving pumps which pressurise seawater that is delivered onshore via a pipeline. Onshore, the high-pressure seawater is used to drive hydro turbines, generating zero emission electricity. The high-pressure seawater is also used to supply a reverse osmosis desalination plant, also creating zero emission freshwater.
Currently seawater desalination plants are large emitters of greenhouse gases due to the amount of energy required to drive grid-connected pumps that deliver the high pressure seawater to reverse osmosis membranes which remove the salt from the seawater.
The Ceto scheme has one big advantage, it can provide baseload power, unlike wind - when the air is calm, or solar - when it is night. Even on a day when the sea looks flat, there are 30-60cm swells. This means that wave potential along the Western Australian coast from Geraldton, and then along the southern coast of Australia and up the eastern coast as far as the Gold Coast, is particularly good.
A full demonstration plant would today cost around $500 million, but the equipment will eventually become cheaper when it is mass produced. Another Australian company, Oceanlinx, will be one of the participants in the $A60 million Wave Hub project off Cornwall in England. The Sydney-based company will install its oscillating water column (OWC) plant, which has been tested at Port Kembla, and which has water rising and falling inside a chamber past a turbine.
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