We just returned from a 75 day cruise to Maine. Our ice box, like most, is not insulated, except for the reflectex we put in about 10 years ago. It helps, but is no solution. We have a refrigeration unit that takes about 4.5 amps when it runs. When at anchor for several days, we would have to run the engine to cool down the icebox when the ice was getting thin.
This year I decided to install a solar panel. 85 watt Kyocera that mounts similarly to Larry DeMers' installation. During the entire trip we never had to run the engine at anchor, and that includes the 5 days we sat at Atlantic City waiting for non-Northerly winds. There were times we had no ice left for days and the solar panel (or engine, when we were moving) kept the bottles of water cold or frozen, and the rest of the icebox ~39-45 degrees. We could get away with running the refrigeration at a duty cycle of about 50% when at anchor because we didn't always get the full amperage from the panel due to swinging, clouds, etc. That meant that we were pretty much breaking even during cloudy days as far as amp hours used. When the sun was out, we had a surplus.
For the days that we had the panel sucking up photons (about 65 days) we generated 965 ah, about 15ah/day. It rained a lot in Maine.
Bob
Ice box p-trap
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