[thedoc]

paul  asked the Naked Scientists:
   
Hi Dr Chris Smith.

I am looking for a fan to drive a generator to produce electricity. Using a one metre diameter pipe mounted 90 degrees in seawater using the air produced to rotate the fan turning in the same direction. Will the air flow back and forth over the blades?

Regards

Paul scholtz

What do you think?

[Mazurka]

That sounnds a little bit like this...
http://www.darvill.clara.net/altenerg/wave.htm

(which as you scroll down has a little bit about other wave power generation schemes.)

The biggest problem with using air to move a fan/ turbine is that as compared to water it has a relatively low energy density - which is why (in the simplest terms wind turbine blades are several times longer (for a given energy output)  than those of a water turbine.