images: Dartmouth Wave Energy
Here’s a wave power technology which you may not have heard of: It’s called the Searaser and (though only in prototype stages, I’ve got some reservations about how well it may scale up, as well as the name which somehow I always see as 'Sea Eraser') it may be worth watching.
The principle is fairly simple and proven in a different context: Use the Searaser to pump quantities of sea water up a hill where it can be stored in ponds until needed and then released downhill to drive hydroelectric turbines to create power. This is how the Searaser works:Searaser Pumps Water As It Rises & Falls on Waves
The device is attached to the sea floor by a flexible tether which allows the Searaser to move up and down with the motion of the ocean. By using a double piston action, the Searaser can pump water both as it rises and falls on waves.
The prototype has successfully pumped water up a 160 foot hill though a pipe, but a full sized Searaser could potentially pump water up 650 feet. According to an article in the TimesOnline each of the full-sized units could generate about 0.25 MW of power and would obviously have to be used in massed quantity to generate sizable amounts of power.
Could Also Be Used Without a Nearby Hill
Even if you don’t have a convenient hill to create a storage pond, the product’s creator, Alvin Smith, explains that the Searaser still could generate power:
If high ground is not available or unsuitable for storing the water for the impulse turbines, the pressurised water pumped via an accumulator direct from the waves will be of sufficient pressure to drive the turbine generators near sea level. These are based on land or offshore rigs, or indeed afloat. The disadvantage of no high head storage is no guarantee of on-demand energy!
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