Wave power has been one of those in-another-five-years kind of energy sources that never quite seems to make it off the drawing board. With any luck, though, Britain is set to launch the world's first commercial wave farm, and the most powerful device of its kind, to be located in northern Ireland (google map).

Next Saturday, a barge carrying the tidal contraption will set off from the dock that manufactured the Titanic - no word on if there'll be a band on board. Called SeaGen, the installation will generate 1.2 megawatts, producing enough power for 1000 homes. Installation of the single-turbine system will be done via crane barge,  will take 14 days to complete, and is scheduled to be operational later this year.

Marine Current Turbines Ltd, developer of the technology, already has an experimental 300kW tide-based generator in Devon, UK. Unlike its prototype predecessor, theSeaGen turbine can generate electricity with both incoming and outgoing tides.

Tidal stream turbines work in much the same way as wind turbines. However, because water is 800 times denser than air, similarly rated tidal turbines need only half the wingspan of their air-powered cousins. TheSeaGen system will have dual rotors that spin in opposite directions. This setup is often preferred because one rotor setups can become unstable, whereas dual rotors offset oneanother's torque. The rotors can be raised above water level for maintenance.

Marine Current Turbines has other tidal projects in the works, including a 3.6 megawatt project off the coast of Vancouver, British Columbia and an ambitious 10.5 megawatt farm in Wales planned for 2011-2012.