[extropy-chat] RE: Re: Anti-hurricane engineering RE: Re: Anti-hurricane engineering RE: Re: Anti-hurricane engineering

[Ody777 at comcast.net]

Adrian Tymes wrote:

<<OTECs essentially work by conducting heat from the
top of the ocean to the bottom, right?  (No energy
needed - indeed, they produce electricity.)  Would
this not effectively result in a (relatively) cold
spot up top, especially if some OTECs were designed to
emphasize conduction over electricity generation?>>

I’m no engineer, but as I understand it, the Ocean Thermal process requires HEATING UP the cold water.  There are three steps: 

(a)  “heat transferred from the warm surface sea water causes a working fluid... to turn to vapor.”

(b)  “The expanding vapor drives a turbine attached to a generator which produces electricity.”  

(c) “Cold sea water passing through a condenser containing the vaporized working fluid turns the vapor back into a liquid which is then recycled through the system.”

(From http://www.hawaii.gov/dbedt/ert/otec_hi.html#anchor356606 .)

The third step must heat up the cold water.  If there were any relatively cooler water left over from this process, I assume you’d just want to use it for the same purpose, to generate more electricity, until it was the same temperature as the surface water.  So there wouldn’t be any “cold spot” produced.

Somebody who knows thermodynamics could probably explain it better.


Rob Masters