As I want to do more sailing in the low latitudes but do not like to
sleep in sweat, I have been looking into ways to cool my boat with
semi-passive means. One thing most boats have is lots of sunlight and
a lot of water for cooling. So, we have a source of heat and a way to
get rid of heat, you should be able to use that to cool air. Turns
out there is a way to do this, adsorption cooling.
Such a system uses a material like Zeolite that quickly adsorbs water
from a reservoir thus reducing pressure and cooling. This can be used
to cool air. The zeolite must then be regenerated to remove the water
and this is done by heating it and then allowing it to cool.
So, we use a solar concentrator to regenerate the zeolite and a 12 V
pump and a 12 V fan. The Zeolite is cooled by pumping seawater thru
coils imbedded in it. Not driving a compressor makes this easy to do
with 12V and very efficient.
Thus one could operate an AC unit from a solar panel and a solar
concentrator. No, it would not reach meat locker temps but compared
to 100 degrees and 100% humidity, 80 degrees and 80% humidity is
paradise. Thoughts?

On 3/2/11 2:43 PM, Frogwatch wrote:
As I want to do more sailing in the low latitudes but do not like to
sleep in sweat, I have been looking into ways to cool my boat with
semi-passive means. One thing most boats have is lots of sunlight and
a lot of water for cooling. So, we have a source of heat and a way to
get rid of heat, you should be able to use that to cool air. Turns
out there is a way to do this, adsorption cooling.
Such a system uses a material like Zeolite that quickly adsorbs water
from a reservoir thus reducing pressure and cooling. This can be used
to cool air. The zeolite must then be regenerated to remove the water
and this is done by heating it and then allowing it to cool.
So, we use a solar concentrator to regenerate the zeolite and a 12 V
pump and a 12 V fan. The Zeolite is cooled by pumping seawater thru
coils imbedded in it. Not driving a compressor makes this easy to do
with 12V and very efficient.
Thus one could operate an AC unit from a solar panel and a solar
concentrator. No, it would not reach meat locker temps but compared
to 100 degrees and 100% humidity, 80 degrees and 80% humidity is
paradise. Thoughts?

Yeah, buy a boat more suitable for your needs, one with a diesel
generator that can power an A/C system.

In article fce2f2ae-ac61-410b-8d98-1f91d8dfe8a4
@u24g2000prn.googlegroups.com, says...

As I want to do more sailing in the low latitudes but do not like to
sleep in sweat, I have been looking into ways to cool my boat with
semi-passive means. One thing most boats have is lots of sunlight and
a lot of water for cooling. So, we have a source of heat and a way to
get rid of heat, you should be able to use that to cool air. Turns
out there is a way to do this, adsorption cooling.
Such a system uses a material like Zeolite that quickly adsorbs water
from a reservoir thus reducing pressure and cooling. This can be used
to cool air. The zeolite must then be regenerated to remove the water
and this is done by heating it and then allowing it to cool.
So, we use a solar concentrator to regenerate the zeolite and a 12 V
pump and a 12 V fan. The Zeolite is cooled by pumping seawater thru
coils imbedded in it. Not driving a compressor makes this easy to do
with 12V and very efficient.
Thus one could operate an AC unit from a solar panel and a solar
concentrator. No, it would not reach meat locker temps but compared
to 100 degrees and 100% humidity, 80 degrees and 80% humidity is
paradise. Thoughts?

I would take two hoses and hang them 10 feet or more into cooler water
and pump fresh sea water through a radiator like in an AC. Then set up a
fan to direct cabin air through the radiator (like an AC) which would
suck heat from the cabin air and pump it back into the ocean (this would
be an open system, fresh water in, heated water out... and probably
expel cooler air back into the cabin. The amount of cooling would depend
on the water temps at the level you are taking it from. Theoretically is
shouldn't make a lot of difference how deep you go in relation to the
pump, to a reasonable extent, either... Right??

On Wed, 2 Mar 2011 11:43:56 -0800 (PST), Frogwatch
wrote:

Thus one could operate an AC unit from a solar panel and a solar
concentrator. No, it would not reach meat locker temps but compared
to 100 degrees and 100% humidity, 80 degrees and 80% humidity is
paradise. Thoughts?

Sounds to me like you need a windscoop.

http://www.defender.com/product.jsp?path=-1|6880|301241&id=48974

On Wed, 02 Mar 2011 15:53:48 -0500, wrote:

A good shade will do
more than what you are talking about. I am not sure how that affects
the "sailing" part tho.

You're on the right track with the shade, and keeping cool is mostly
an issue when anchored or docked. The combination of good, full
length awnings/shades, a wind scoop or two, and some 12 volt fans down
below will usually get the job done in the Bahamas. The only time we
run the air conditioning at night is when docked. Anchored out, we'll
run the generator for an hour at bedtime to charge the batteries, ice
down the fridges, and cool off the boat before turning in.

On Mar 2, 6:55*pm, Wayne.B wrote:
On Wed, 02 Mar 2011 15:53:48 -0500, wrote:
A good shade will do
more than what you are talking about. I am not sure how that affects
the "sailing" part tho.

You're on the right track with the shade, and keeping cool is mostly
an issue when anchored or docked. * The combination of good, full
length awnings/shades, a wind scoop or two, and some 12 volt fans down
below will usually get the job done in the Bahamas. *The only time we
run the air conditioning at night is when docked. *Anchored out, we'll
run the generator for an hour at bedtime to charge the batteries, ice
down the fridges, and cool off the boat before turning in.

Maybe I think this is a problem because I spend so much time here in
NW FL where there is no wind in the summer. If there is wind, the
windscoop works very well.