Our cavernous ice chest and antique cold plate system was clearly not going to work with our energy conservation plans so we lined the interior of the stainless steel ice chest with a minimum of 2" of new insulation and built a new fiberglass liner using pre-formed panels. We the installed a Seafrost 12V system with a freezer bin and ETT controller.
We had limited expectations based on all the refrigeration stories we had read but the result has been absolutely first class. The stuff in the freezer bin stays frozen, the stuff not in it does not freeze and we can make as much ice as we need. What more could you ask?
It is an air/water system and we generally run it on water cooling as the lazarette gets pretty hot. The water pump is a little obtrusive under the galley floor but I plan to move it into the engine compartment at some point.

Seafrost