Wave-powered desalination pump permitted in Gulf  

CNet has an article on a wave powered desalination device in the Gulf Of Mexico (hopefully it will work even when covered in a coating of BP provided oil) - Wave-powered desalination pump permitted in Gulf.

The waters of the Gulf of Mexico will see a novel offshore platform later this year, one that will use wave power to desalinate water.

Independent Natural Resources, which makes the Seadog water pump, on Wednesday said that it has received a permit for a wave power generation facility off the coast of Freeport, Texas. The company says it's the first to receive a "section 10 permit" from the U.S. Army Corps of Engineers to operate a wave generator in the U.S.

The facility, which the company hopes to put in the water by the end of the year, will be a platform with 18 wave pumps underneath it. Each pump, which is about seven feet in diameter, will send water up through three water wheels connected to a generator. The electricity from the generator will be used to power a standard reverse osmosis desalination machine.

The wave energy generator is larger than Independent Natural Resource's prototype machines which it installed in 2007 but this new facility is sized to operate at commercial scale in Gulf waters. Rather than sell electricity or water, though, operators will be taking data to measure impact on sea life, the generator's performance, and the cost of operation, said Douglas Sandberg, the vice president of the privately funded company.

The platform will be about 150 feet by 75 feet in area and be 1 mile offshore to take advantage of swells. The pumps themselves will work 25 feet below the surface of the water and be able to generate about 60 kilowatts.

The efficiency of the system in converting wave energy to electrical energy is about 22 percent but can get over 50 percent, Sandberg said. Rather than only convert the energy of an incoming wave, the pump also captures some of the potential energy of air movement in the pump, he explained. The electricity generated on board will be used to power the facility and desalinate 3,000 gallons of water a day for testing, although it's capable of doing 20 times that, according to the company.