Wave power could supply 16 percent of the world's energy needs

[txlibdem]

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x297161

http://www.oceanpowertechnologies.com/products.htm - shows a buoy that generates electricity from the waves
--- the company has a 150kW model and are working on a 500kW version.

Wave power can't be harnessed everywhere. Wave-power rich areas of the world include the western coasts of Scotland, northern Canada, southern Africa, Australia, and the northeastern and northwestern coasts of the United States. In the Pacific Northwest alone, it's feasible that wave energy could produce 40–70 kilowatts (kW) per meter (3.3 feet) of western coastline. The West Coast of the United States is more than a 1,000 miles long.

http://www.energysavers.gov/renewable_energy/ocean/index.cfm/mytopic=50009

[mdmc]

1. thanks OP

[txlibdem]

3. Thank you

This to your avatar: But NOT thank you for failing to Rapture me the other day. I was pissed off for hours! J/K

[muriel_volestrangler]

2. Interesting mismatch in the numbers

OPT says the 150kW model has a capacity factor of 30 to 50%. So call it 40%, and that's 60kW on average from it. It's 36 feet wide - about 11m. So that's 60kW/11m - about 5kW/m, given there will be at least a small amount of interference with the waves just outside the direct 'shadow' of the device. Very different from 40-70kW/m - which would seem to be a theoretical maximum, rather than anything any existing design is claimed to make.

Sustainable Energy - Without the Hot Air (written by a Cambridge professor who is Chief Scientific Advisor to the British Department of Energy and Climate Change) says 40kW/m is the total amount of Atlantic wave energy. The Pelamis machine is estimated, by its manufacturers, to be able to get 6kW/m.

[txlibdem]

4. Darn, that's a tiny discrepancy, eh? ;-)

Sheesh! Maybe their employees used to be used car salesmen??? Just kidding.

But, to be fair to the wave energy folks, the linked article did say that the pacific coast is 1000 miles so that's still a lot of potential energy.

Hypothetically, if we covered 10% of the pacific coast and got 5kW/m... (100 miles is 166 kilometers, 166,000 meters) times 5kW = 830,000 kW, 830 MegaWatts. It would take a little over 15,000 of those "150kW" units...

PS, different ocean regions have different wave energy potential. The Pacific Northwest varies from 40-70kW/m potential, I think your source is correct about European shores having 40kW/m. Some other areas have 20kW/m energy potential. I guess it's just like every other renewable energy source, some places are better than others.

[OnlinePoker]

5. The company's park in Oregon

I don't know how far along they've progressed, but here is a planned park they are doing in Oregon.

http://www.oceanpowertechnologies.com/reedsport.htm

It's a 1.5 MW development that the company says will produce 4140 MWH/year. I did some quick calculations... 1.5MW*24*365 = 13140 MWH capacity for the year. The 4140 MWH/year forecast is a capacity factor of 31.5% if it actually produces that much.

[txlibdem]

6. Their Coos Bay, OR site shows much seasonal variation in energy potential

From 10kW/m in July to 40kW/m in January and December. I guess we better have some extra solar power thrown into the mix to make up for it!
...http://www.oceanpowertechnologies.com/coos.htm

Which I'm just fine with, by the way. Solar alone can supply 100% of all our energy needs given enough excess capacity and enough energy storage. Wave power is just icing on the cake. The more renewable energy, the better!

Who knows, maybe people will go back to electric heaters in the winter (when the highest energy output from the waves are).

[OnlinePoker]

7. Here is another company working hard on wave energy

http://www.pelamiswave.com/

[txlibdem]

8. Pelamis P2

Rated power: 750kW
Structure: 180m long, 4m diameter, 1300te displacement (mostly ballast)
Water depth: >50m
Mooring type: Compliant, slack moored
Conversion efficiency: ~70%

I'd definitely like to see more actual test results.