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Glenn Ashmore
 
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That is so far off that I just have to reply. I am not doing this as a
rebuttal to your asinine comments but for the benefit of those lurkers who
might be interested in the thought process.

The TOTAL cost of my refrigeration system is a little under $4K including
the vacuum insulation, separate keel cooled compressors for the freezer and
refrigerator, custom made double sealed lids with solid surface tops and the
materials for the cabinet work. Under the worst case load it will consume
about 90 amp hours. My alternator produces 270 amps and the battery bank is
a little over 800 amp hours so the average charge time required for
refrigeration will be about 20 minutes assuming no output from the solar
panels.

If you want to consider ALL the cost of the batteries, alternators, 3 stage
regulator and solar panels as exclusively used for refrigeration add another
$3K. But that is not really fair because refrigeration is only 1/3 of my
energy budget. A fair figure for the total cost of my refrigeration system
is about $5K.

If I were really considering this project on a cost accounting basis I would
not own a boat in the first place but money in excess of that required to
survive comfortably is useless unless you can have some fun with it. But
lets give a little cost accounting a try and see what happens. To estimate
the real cost of the system we need to make some assumptions. First we
amortize the capital costs. Let's assume over an economic life of 10 years
at the end of which an additional $3,000 will be required to refit the
mechanical parts and vacuum panels. Assuming an average use of 120 days a
year that works out to about $4.40/day including opportunity cost of the
capital at 6%.

Now let's consider the operating costs. Two unshaded 150 watt solar panels
in the tropics should be expected to optimally produce about 160 amp hours
of charge. But things are never optimal so to be conservative we will
assume only 25% or 40 amp hours (that is average. Not every day.) so the
engine must provide the remaining 50 amp hours or about 12 minutes of run
time. From a separate calculation of engine expenses that includes capital
costs, overhauls, oil, general maintenance and fuel at $4/gallon over the
service live, that is about $1.20 ignoring the 5 gallons of water that will
be produced at the same time and the value of any forward progress the boat
makes.. For good measure, lets throw in another $360/year reserve for
repairs. So the total cost of the system can be conservatively estimated at
about $6.60/day. Obviously not as good as the $.60 to $1.00 a day that a
home refrigerator cost but about the middle of the cost range for marine
refrigeration.

For comparison, a simple $300 foam insulated ice box of similar capacity
will require about 3,600 BTUs a day or 25 pounds of ice. The current price
of a 10 lb. bag of ice in the Bahamas and Virgin Islands is $2.50 and
considerably higher in Martinique, St. Martin and other Caribbean islands.
That works out to about $6.25 a day with no freezer and not including the
value of lost personal time constantly having to get more ice.

--
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

"JAXAshby" wrote in message
...
Jax, you still don't have a clue.


Really, Glenn? But I am not the one with $18,000 dollars stuck into a

reefer
system that requires me to run the engine for three hours a day.