December 17, 2007 9:00 PM PST

Wave power to go commercial in California

Sea power may finally be on the horizon.

Pacific Gas & Electric, the large Northern California utility, has signed a power purchase agreement with Finavera Renewables for 2 megawatts of electricity that will come from a wave farm, which Finavera will build 2.5 miles off the coast near California's Humboldt County.

Ideally, the wave farm will start producing power in 2012. It will offset 245 tons of carbon dioxide annually, and if it succeeds, Finavera will expand the wave farm to 100 megawatts.

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"With PG&E behind us, we will be able to go to a bank, if we can show there is no technology risk, to get financing," said Jason Bak, Finavera's CEO, in an interview. The exact location of the wave farm will be determined by the location of onshore power lines and electrical stations.

Finavera makes a device called the Aquabuoy, a buoy connected to a long underwater piston. As the buoy bobs up and down on the waves, it pushes the piston, which pressurizes a chamber filled with seawater. The pressure cranks a turbine and electricity is made.

A full-scale buoy from Finavera will be capable of generating 250 kilowatts, enough for 80 homes. The 2-megawatt field will consist of eight devices. A 100-megawatt array of them could be squeezed into a few square miles on the sea.

Several companies and university laboratories are experimenting with ways to harness tides and waves to produce power. Some small-wave and tidal-power devices exist, but mostly it's an industry in the experimental phase. Unlike wind or sunlight, waves and tides are fairly predictable, a major plus for utilities looking for stable green sources of power.

Sea water is also more than 800 times denser than air at sea level, which means wave farms or tidal turbines can produce quite a bit of power with only a little equipment and real estate.

Ten years from now, the U.S. could produce 10 gigawatts of wave power and 3 gigawatts of tidal power, said Roger Bedard, ocean energy program leader for the Electric Power Research Institute and an admitted optimist on the subject. That's enough for 4.3 million homes (assuming 3 kilowatts a home).

Challenges and costs
Bedard further estimated that there is a potential 2,100 terawatt-hours worth of wave energy off the shores of the U.S. and 250 terawatt-hours of it could be harvested economically. That's about 6 percent of U.S. electrical demand.

The catch? Neptune doesn't play ball. A prototype Finavera put in the ocean off the coast of Oregon sank at the conclusion of a recent test. The company was trying to pull the buoy out of the sea when it began taking on water and sank. Finavera will try to recover it in January and determine what went wrong. A valve may have accidentally opened, said Bak.

"The main thing we learned is 'make sure you have a lot of air bags handy,'" he said. "With more air bags, the boat could have towed it to shore."

Verdant Power, which put six tidal turbines in New York's East River earlier this year, found that the strong currents have been shearing the tips of the rotor blades and bending some of the bolts that hold on the blades.

On the bright side, these are likely conquerable problems. The Aquabuoy actually performed well on tests prior to the mishap, Bak said.

Building this equipment, inserting it into place, and then connecting wave and tidal systems to the grid with underwater cables also costs quite a bit. Finavera's long-term goal is to have the Aquabuoys produce power at 5 to 8 cents per kilowatt hour. That's more expensive than coal (3 cents) or natural gas (4 to 5 cents) but less than offshore wind turbines (15 cents) or solar (18 or more cents, depending on the circumstances.)

"We want to be cheaper than offshore wind," he said.

Environmental concerns are also a major issue. Most wave technology can't be seen from shore, but it can get hooked into boat engines and, possibly, disturb marine life. Over the next three years, Finavera will be in contact with groups and organizations that have an interest in the coastline, including crabbers, surfers, and residents, Bak said.

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18 comments

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Someone will Block it!
Good things don't happen in California because we have too many "Do Gooders" looking out for our Happiness oh yes and Inviroment. The Turbin blades will probably kikk a fish or slow down tidal action and a lawsuit will be filed to save the ocean Inviroment and a Judge will say NoNo Bad idea using the Sea to Produce electricity.We can make plans for a better tomorrow we just cn't implement those plans . we are a victim of our Inviromentalist!
Posted by sterling3 (4 comments )
Reply Link Flag
It's a Great idea and about time we tried it!
The buoys are much more stable and take up less space than the long tubular attempts at harvesting wave power. Most environmentalists, supporrt wave energy and by the way designed these prototypes.
Posted by triciamays (4 comments )
Link Flag
Someone will Block it!
Good things don't happen in California because we have too many "Do Gooders" looking out for our Happiness oh yes and Inviroment. The Turbin blades will probably kikk a fish or slow down tidal action and a lawsuit will be filed to save the ocean Inviroment and a Judge will say NoNo Bad idea using the Sea to Produce electricity.We can make plans for a better tomorrow we just cn't implement those plans . we are a victim of our Inviromentalist!
Posted by sterling3 (4 comments )
Reply Link Flag
It's a Great idea and about time we tried it!
The buoys are much more stable and take up less space than the long tubular attempts at harvesting wave power. Most environmentalists, supporrt wave energy and by the way designed these prototypes.
Posted by triciamays (4 comments )
Link Flag
Someone will Block it!
Good things don't happen in California because we have too many "Do Gooders" looking out for our Happiness oh yes and Environment. The Turbine blades will probably kill a fish or slow down tidal action and a lawsuit will be filed to save the ocean Environment and a Judge will say No! No !Bad idea using the Sea to Produce electricity.We can make plans for a better tomorrow we just can't implement those plans . we are a victim of our Enviromentalist!
Posted by sterling3 (4 comments )
Reply Link Flag
I agree - Environmentalists will kill it
I couldn't agree more with sterling3. The whole time I was reading the article I was waiting for the negative 'environmentalist' angle to appear and lo and behold - there it was near the end. Good luck with that.
Posted by chambcm (19 comments )
Link Flag
Someone will Block it!
Good things don't happen in California because we have too many "Do Gooders" looking out for our Happiness oh yes and Environment. The Turbine blades will probably kill a fish or slow down tidal action and a lawsuit will be filed to save the ocean Environment and a Judge will say No! No !Bad idea using the Sea to Produce electricity.We can make plans for a better tomorrow we just can't implement those plans . we are a victim of our Enviromentalist!
Posted by sterling3 (4 comments )
Reply Link Flag
I agree - Environmentalists will kill it
I couldn't agree more with sterling3. The whole time I was reading the article I was waiting for the negative 'environmentalist' angle to appear and lo and behold - there it was near the end. Good luck with that.
Posted by chambcm (19 comments )
Link Flag
Two companies have demonstrated success
I am wondering why the company whose buoy sank is getting the "green" light, when two other companies have demonstrated successful long-term power generation from the waves. Scotland's Wavegen (now a division of Voith-Siemens) has been feeding the UK national grid for years with its at-shore wave energy converter, Limpet. Ocean Power Technologies of New Jersey has demonstrated its own, offshore PowerBuoy for years, including a successful demonstration project for the US military. OPT is moving ahead with plans to put a wave power farm in Oregon near Reedsport, and I have long wondered why they haven't pursued (or been invited to participate in) any California-based projects. I guess we'll see which gets up and running first: PowerBuoy or AquaBuoy?
Posted by James Anderson Merritt (251 comments )
Reply Link Flag
and a third...
"CETO" by REH and Carnegie Corp is also undergoing testing and looks promising.
Posted by zaphod1 (2 comments )
Link Flag
Two companies have demonstrated success
I am wondering why the company whose buoy sank is getting the "green" light, when two other companies have demonstrated successful long-term power generation from the waves. Scotland's Wavegen (now a division of Voith-Siemens) has been feeding the UK national grid for years with its at-shore wave energy converter, Limpet. Ocean Power Technologies of New Jersey has demonstrated its own, offshore PowerBuoy for years, including a successful demonstration project for the US military. OPT is moving ahead with plans to put a wave power farm in Oregon near Reedsport, and I have long wondered why they haven't pursued (or been invited to participate in) any California-based projects. I guess we'll see which gets up and running first: PowerBuoy or AquaBuoy?
Posted by James Anderson Merritt (251 comments )
Reply Link Flag
and a third...
"CETO" by REH and Carnegie Corp is also undergoing testing and looks promising.
Posted by zaphod1 (2 comments )
Link Flag
Yeah...sounds great, but...
Wait until the first sea lion gets caught up in it...

Cynical? You bet.
Posted by RacerX7 (24 comments )
Reply Link Flag
Yeah...sounds great, but...
Wait until the first sea lion gets caught up in it...

Cynical? You bet.
Posted by RacerX7 (24 comments )
Reply Link Flag
This is such old news.
Way back when in 2000 Wavegen installed a limpet on the Isle of Islay, off the Scottish coast. The limpet uses an oscillating water column to pressurize air in a tunnel. The air moves the fins of a turbine. The turbine produces electricity.

<a class="jive-link-external" href="http://www.wavegen.co.uk/what_we_offer_limpet_islay.htm" target="_newWindow">http://www.wavegen.co.uk/what_we_offer_limpet_islay.htm</a>

This one device, which has minimal impact on the local environment, has been optimized to produce between 15 - 25 kWh/m. Not sure if that "m" means Month or Minute though.

Still, I'm glad to see someone taking a stab at helping the US break their dependency on foreign oil. To bad Congress won't let us drill for our own oil.
Posted by magicman73 (190 comments )
Reply Link Flag
This is such old news.
Way back when in 2000 Wavegen installed a limpet on the Isle of Islay, off the Scottish coast. The limpet uses an oscillating water column to pressurize air in a tunnel. The air moves the fins of a turbine. The turbine produces electricity.

<a class="jive-link-external" href="http://www.wavegen.co.uk/what_we_offer_limpet_islay.htm" target="_newWindow">http://www.wavegen.co.uk/what_we_offer_limpet_islay.htm</a>

This one device, which has minimal impact on the local environment, has been optimized to produce between 15 - 25 kWh/m. Not sure if that "m" means Month or Minute though.

Still, I'm glad to see someone taking a stab at helping the US break their dependency on foreign oil. To bad Congress won't let us drill for our own oil.
Posted by magicman73 (190 comments )
Reply Link Flag
Expensive toys
These sound great but does little to decrease fossil fuel power generation. It's all non-firm, as available power that utilities cannot count as base load generation. Only reason why utilities pay for such expensive nonsense at this point (I'm not saying it won't make sense at some future point) is that the total installed capacity counts toward them meeting the renewable standards. Much like wind power, total installed capacity doesn't come close to what will actually be produced. Since we all end up paying for these expensive power anyway, a better approach would be to encourage conservation by mandating a tiered electricity rates for consumers based on use. Heavy residential users of electricity would pay higher prices for excessive use.
Posted by oxtail01 (308 comments )
Reply Link Flag
Expensive toys
These sound great but does little to decrease fossil fuel power generation. It's all non-firm, as available power that utilities cannot count as base load generation. Only reason why utilities pay for such expensive nonsense at this point (I'm not saying it won't make sense at some future point) is that the total installed capacity counts toward them meeting the renewable standards. Much like wind power, total installed capacity doesn't come close to what will actually be produced. Since we all end up paying for these expensive power anyway, a better approach would be to encourage conservation by mandating a tiered electricity rates for consumers based on use. Heavy residential users of electricity would pay higher prices for excessive use.
Posted by oxtail01 (308 comments )
Reply Link Flag
 

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