"Pete C." wrote in message
...
Ed Huntress wrote:
snip

Unless you're talking about wave generation, my impression of tidal is
that
it's hellishly intrusive on the coastal environment. You have to dam
something up to make it work.

Am I wrong about this?

The tidal generation I'm referring to involves no dams and no waves, it
is based on solidly anchored buoys. When the tidal level lowers the buoy
anchor cable retracts into the buoy to remain tight to the ocean floor.
When the tide comes in the buoyancy of the buoy produces tremendous
tension on the anchor cable which is used to spin the generator as the
buoy slowly rises (and the anchor cable extends) until the tide maxes
out. There were some recent innovations in this design that simplified
it and improved efficiency.

At any rate, a low profile buoy bobbing up and down with the tide has
extremely low environmental impact and there is a massive amount of
available energy at high densities waiting to be captured.

That certainly sounds interesting, and it sounds extremely simple. Why don't
we have them now?

--
Ed Huntress