Actually, with the introduction of the higher powered and more efficient
Danfoss 50 and 80 compressors Nigel has seen the light and come over to the
DC evaporator side. He wrote a good article in Ocean Navigator a few months
back explaining the trade offs between constant cycling evaporators and
engine driven holding plate systems.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Bruce in Bangkok" wrote in message
...
On Sat, 22 Mar 2008 09:19:58 -0400, "Roger Long"
wrote:

With a small engine like mine and modest electric loads otherwise,
wouldn't
it me more efficient to put the largest compressor that a toothed belt
pully
and engine PTO limitations would permit on the front end of the engine?
Then have a large cold plate in the box and draw it down as quickly as
possible keeping the engine under maximum load. It wouldn't give you the
fine temperature control of a constantly running 12 V. fridge system but
would be as good as ice. Drawing down the cold plate would be like
buying
ice (and probably nearly as expensive at next year's fuel costs).

The conversion from fuel to electricity to charging and back to motive
force
has got to use up more fuel than just running the compressor directly.

Most of the boats I see here use exactly that system. The more
up-market ones have a duel system with both engine driven and A.C.
powered compressors for use at sea and in the marina.

If you really want to get into it find a copy of Nigel Calder's book
on refrigeration systems (he is a fellow Mainiac. It is down to earth
and really teaches you how to build a system.


Bruce-in-Bangkok
(correct email address for reply)