On Mon, 12 Jan 2004 16:28:35 -0800, "Rod McInnis"
wrote:


"Larry W4CSC" wrote in message
...


I've never figured out why boats in cold climates waste all this
energy going out the exhaust. It's SO easy to make a cast iron heat
exchanger in a dry stack, right next to...or even right IN the exhaust
manifold that will just roast your ears with free heat.

the old Volkswagon Beetles used a heat exchanger off the exhaust manifolds
to heat the car! It was actually pretty nice on cold mornings, as the
heater worked almost instantly after starting the car.

Yes, and it heated near instantly as you started the cold engine.
Didn't take long to heat the heat exchanger directly in the flames!

My VW 411 station wagon with the Porche 914 pancake engine in it did
it even better.....It had a gasoline furnace you could turn on BEFORE
starting the car by turning on a timer on the dash that limited how
long it would run without starting the car. It was like heating with
a jet engine....and sounded like one!


We retrieve some of it with the hot water heater hooked to the water
jacket. Too bad so much heat is simply wasted.


There is a lot of free heat to be had from the engine. The only drawback is
that the engine has to be running! Not what you want when you are swinging
on the hook!

Agreed, but I suppose it would depend on how cold your feet are...(c;

For those times, perhaps what is needed is a black plastic water
heater you could haul up the mainmast to heat some medium for the
night. There's more to solar energy than battery chargers that are 2%
efficient. I know someone who has homemade panels hanging from the
sunny side window sills to the ground below. When the sun shines on
them, it superheats the air on the front of the panel. This air rises
and enters the room through the window sill opening. The hot air
rising sucks house air from the bottom side of the sill into the heat
exchanger to replace that already heated.

When he first built them, he made one for every window. His living
room has 3 that sun hits. Fed up with sweating at 90F, he reinvented
thermostatic dampers to control how MUCH of the hot air was allowed
into the house. At first it was like a furnace out of control! A
boat model could simply be a vertical panel hung over the hatch with a
simple 12V muffin fan to force the air up into the panel which can't
be self-flushing like his home system is. With all the boat stink
problems everyone has, maybe a solar panel could have an opening
outside, heat the air then let the fan suck it into the boat to
displace stinky, wet air out through another hatch.....the leaky one
into the cockpit on a sailboat. Wouldn't hot fresh air be nice all
day in winter?

"Larry W4CSC" wrote in message
...
efficient. I know someone who has homemade panels hanging from the
sunny side window sills to the ground below. When the sun shines on
them, it superheats the air on the front of the panel. This air rises
and enters the room through the window sill opening. The hot air
rising sucks house air from the bottom side of the sill into the heat
exchanger to replace that already heated.

Before they went to flush toilets, the campground we used in Maine as a kid
had 'solar holers' and solar showers. The solar holers were "restroom"
outhouses - like a multiple stall restroom but no water - with south facing
black-inside/clear-top vertical risers with the intake at the bottom and the
exhaust well above the roof of the outhouse, which pulled fresh air through
the outhouses and out the top. No stinky outhouse. Likewise, the hot water
in the showers was a solar black-pipe covering on the bath house roof,
faciing south. Summer in Maine has a *lot* of sunshine hours, so they never
ran out of hot water unless it was raining...

Marvelous thing, the sun....

L8R

Skip

--
"And then again, when you sit at the helm of your little ship on a clear
night, and gaze at the countless stars overhead, and realize that you are
quite alone on a great, wide sea, it is apt to occur to you that in the
general scheme of things you are merely an insignificant speck on the
surface of the ocean; and are not nearly so important or as self-sufficient
as you thought you were. Which is an exceedingly wholesome thought, and one
that may effect a permanent change in your deportment that will be greatly
appreciated by your friends."- James S. Pitkin

"Larry W4CSC" wrote in message
...


For those times, perhaps what is needed is a black plastic water
heater you could haul up the mainmast to heat some medium for the
night.

What you would need is thermal mass. The key word here is "mass". It will
take a lot of it, if you intend to pull heat out of it all night long. And
it will be heavy. How much weight would you feel comfortable hauling up the
mast?


I know someone who has homemade panels hanging from the
sunny side window sills to the ground below.

This works great IF you have a sunny exposure BELOW the area where you use
or store the energy. I have known people who live on a steep hill with a
southern exposure (northern hemisphere, which means that the slope gets a
lot of sun). It is somewhat common to construct a solar heater out of black
ABS pipe that runs down the hill a ways. Heating swimming pools is common,
but I know one person who had copper pipes embedded in the concrete slab of
his home and ciculated the warm water to heat the slab.

The key is that warm air/water will rise, so if the source of heat is lower
you can create a natural flow of water. If the source of heat is above,
then you will need to pump the water, and you may end up using more energy
pumping than you would have heating.

Rod

On Wed, 14 Jan 2004 12:36:42 -0800, "Rod McInnis"
wrote:


"Larry W4CSC" wrote in message
...


For those times, perhaps what is needed is a black plastic water
heater you could haul up the mainmast to heat some medium for the
night.

What you would need is thermal mass. The key word here is "mass". It will
take a lot of it, if you intend to pull heat out of it all night long. And
it will be heavy. How much weight would you feel comfortable hauling up the
mast?

How about we transfer the heat into the thousands of pounds of lead in
the KEEL? Is that mass enough??...(c;

I was referring to a way we could heat the cabin in the DAYTIME, to
reduce the cost of load of heating it, not eliminate it. If you
pumped air from the cabin up into a black plastic bag, of sorts,
exposed to the sun, the air coming back out into the cabin would be
more than enough to heat the boat in the daytime....for free.

I know someone who has homemade panels hanging from the
sunny side window sills to the ground below.

This works great IF you have a sunny exposure BELOW the area where you use
or store the energy. I have known people who live on a steep hill with a
southern exposure (northern hemisphere, which means that the slope gets a
lot of sun). It is somewhat common to construct a solar heater out of black
ABS pipe that runs down the hill a ways. Heating swimming pools is common,
but I know one person who had copper pipes embedded in the concrete slab of
his home and ciculated the warm water to heat the slab.

Agreed, hence the FAN to overcome the problem, forcing air to
circulate against its will into and out of the bag.

The key is that warm air/water will rise, so if the source of heat is lower
you can create a natural flow of water. If the source of heat is above,
then you will need to pump the water, and you may end up using more energy
pumping than you would have heating.

Rod

Pumping air into the thing is easy. 12V muffin fans draw almost no
power and move a LOT of air.