Simplifying Tidal Power to Drop Costs
Offshore power generation is usually thought to mean windpower (despite the fact that there is still none in the United States). But other means of extracting energy from near shore regions are being explored, as well. And a new variety of tidal power generation is one of the latest systems to be explored.
Developed by scientists at NASA's Jet Propulsion Laboratory, the new hydrokinetic system uses tidal turbines to create a high pressure fluid, rather than making electricity with each turbine. The high pressure fluid is driven to shore where the generating turbine is located.
One difficulty for engineers is that electrical cables are needed to go several miles (or more) from the generator to the shore where the power will be used. Undersea cables need to be more than just a couple of wires and have to be safe, even after rough treatment and exposure to ocean conditions. Seawater is very corrosive and that only adds to the need to protect the cabling and the other electrical components. Locating the generating facility on land helps reduce the complexity of the system, and keeps seawater and electricity segregated from each other.
Potentially, the system costs could be lower by using simpler pumping turbines rather than generating turbines in this configuration. Maintenance costs might well be lower, too, since there are no electrical systems that need to be maintained out in the water.




