2008 11 21 OTEC update (Ocean Thermal Energy Conversion)

[mespilus]

http://www.newscientist.com/article/mg20026836.000

[NickW]

http://www.newscientist.com/article/mg20026836.000

Interesting stuff

There was one proposal to put a load of oftec type devices in the Atlantic (West of the Windward Isles) where hurricanes start to form. The idea was that by bringing cool water to the surface this would cool it reducing the intensity / frequency of hurricanes (Hurricanes need sea water temperatures at 25 c plus to form).

I also wonder if by bring up water - possibly nutrient rich this might stimulate the proliferation of sea life and uptake of CO2.

Very interventionist technology and would not be liked by your deep ecologists.

[Amy]

And it might disrupt the Atlantic thermal conveyor current and speed up global warming by reducing the polar ice sheet

[NickW]

And it might disrupt the Atlantic thermal conveyor current and speed up global warming by reducing the polar ice sheet

I maybe wrong but I thought the effect of pulling up cold water from the deeps in the tropics in that area would actually enhance the North Atlantic Conveyor.  The main disruption to the NAC is from large quantities of melting ice reducing the salinity of water in the northern Atlantic.

[dhaslam]

Cooling the surface water of the oceans would be more likely to slow global warming and in any case the ocean would restore its balance naturally.  The problem with this technology is that it has been tried in the past without success and the only change now is more electronics and perhaps better refrigerants.   

[AlanM]

there has also been increased rainfall( 30% ) in the north russian area and those rivers that drain into the arctic basin are also contributing to the decrease in salinity. The salinity levels have been decreasing for decades and the changes will probably keep occurring.
There may be a requirement for more huskies and ice breakers, up here anyway, should the NAC decide to have a rest.

[Amy]

but maybe if you cool tropical water and slow its northern migration, the arctic water becomes more stagnant and less saline

[NickW]

but maybe if you cool tropical water and slow its northern migration, the arctic water becomes more stagnant and less saline

Who knows

Im more concerned at the imminent return of the road warrior

[Ivan]

Interesting, but sad that it hasn't appeared to develop at all since the 1970s.

Having done a quick search, they seem to quote 27C hot side and 5C cold side (probably because all the data comes from Hawaii rather than because these are essential requirements). Makes me wonder how successful it would be to make a (very) small scale unit to generate power based on ground water/air temperature differences. At the moment, the Navitron site ground water is at 13C, and at this time of year, you could regularly expect air temperatures of freezing. Maybe this could be utilised?