Britain: Wave Powered Pistons Will Pump Sea Water Into Reservoirs for On-Demand Electricity Generation
January 27th, 2012My guess is that pigs will fly before this is built out on any meaningful scale, but it looks like an interesting idea.
Via: BBC:
A Devon inventor’s electricity from seawater generator could be sited at 200 points around the UK coastline.
Energy firm Ecotricity wants to develop a commercial Searaser for testing off Falmouth in Cornwall and put hundreds around the coast in five years.
Dale Vince of Ecotricity said the potential was “enormous”.
The Searaser machine works by using wave energy to pump water up to container tanks and the water is then released to a hydro-electric turbine.
Searaser is the brainchild of British engineer Alvin Smith from Dartmouth.
He came up with the idea about 10 years ago while he was playing with an inflatable ball in a swimming pool.
Searaser pumps seawater using a vertical piston between two buoys – one on the surface of the water, the other suspended underwater and tethered to a weight on the seabed.
As the ocean swell moves the buoys up and down, the piston works like a bicycle pump to send seawater through a pipe to an onshore turbine to produce electricity or to a coastal storage reservoir.
It can then be released through a generator as required.
Mr Smith: “There are over 150 reservoirs on our cliff tops already around the south west.
“A lot of these are becoming available.
“The tanks can be large or the size of a family swimming pool.”
He said that a full size machine would be about 1m wide and 12m deep and cost up to £250,000.
The ideal site for machines would be in water about 25m deep near a cliff face.
He is hoping the test machine will be installed off Falmouth in Cornwall by the end of the year.
Related: Pumped-Storage Hydroelectricity
Not quite ecologically benign (salting the earth, so to speak), but a very interesting low(er) tech idea.
They aren’t “salting the earth” when they do this. See: Okinawa Yanbaru Seawater Pumped Storage Power Station:
“The entire inner surface of the reservoir is covered with an impermeable liner to prevent seawater from leaking and damaging the surrounding vegetation.”
After the water passes down through the turbine, it is released back into the ocean.
I changed the headline in case it was causing confusion.
anyone remember the variable water density electric generator while back? i cant seem to find it in the archives, had a huge silo w/ compresed gas or something that just floated up and down, semi-free energy. thought this was that at first, just scaled up, but no, its not.
@pessimistic , I’m not sure if we’re remembering the same thing, but I remember several news stories about wave buoys.
http://peswiki.com/index.php/Directory:Wave_buoys#Permanent_Magnet_Linear_Generator_Buoys
As I recall, several locations were considering them. Some were vetoed by local environmentalists, citing dangers to whales and other marine life. That same concern would be present in every anchored water device (navigation buoys, oil rigs, and even boat anchors).
You have to wonder who drives some of these groups. Probably the same folks who encouraged the demise of large scale wind farms based on the hundreds of birds per year that could be killed.
Hmmm.. Coal/oil powered plant emissions, nuclear accidents, versus very small scale “potential” risks.
I see the definite risk of pumping large scale sea water inland for existing style hydroelectric plants. We don’t need to make giant salt lakes, no matter how they are protected. It’s unnecessary wasted energy through more conversions. Every time you convert energy from one state to another, you always have losses.
This way, you have:
kinetic/wave -> liner pumped water -> potential lake water -> hydroelectric generator
The wave generators, you have:
kinetic/wave -> electrical
Logically, we should have large scale wave generator farms along the coasts. I doubt it will happen in our lifetimes. Sometimes I wonder how long our “lifetime” will be. I’m surprised the doomsday clock isn’t seconds away from midnight. Well, we are at 4 minutes now. The only way we can beat that is to nuke someone.
http://www.guardian.co.uk/news/datablog/2012/jan/11/nuclear-atomic-scientists-doomsday-clock
Very interesting. Since this concept includes built-in storage of energy, it could be used to cover the gaps in wind and solar power, for fully renewable energy generation without any need for further advances in battery/hydrogen cell technology.