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12 volt car heater direct to solar panels yes/no?

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Survival Bill

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Sep 28, 2003, 8:10:03 PM9/28/03
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I would like to use a spare solar panel to run a 12 volt car heater would a
4 amp panel be enough and just a fuse in between or will running something
like this directly off a panel damage the panel? I was thinking of using
this to heat the trailer during the day to keep things from freezing during
the day when I am out....

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Solar Guppy

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Sep 28, 2003, 8:29:34 PM9/28/03
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What is the current draw of the heater ?

Regardless , you can directly connect the panel without worries but I
wouldn't get your hopes up about getting the trailer warm off a 50 watt peak
panel


"Survival Bill" <bill...@shaw.ca> wrote in message
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DeJaMooooo

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Sep 28, 2003, 11:30:57 PM9/28/03
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I have a car heater... they draw a lot of power and keep my one hand warm.
Not a good device, maybe you have a better one than I do.

Was informed once by a painter that they put a lightbulb in their paint storage
container and it kept their paint from freezing night and day. The container
was well insulated.

Let us know what works...

Ramble'n Randy
(I have a 65 AMC Rambler Wagon with no working heater fyi)

Doug Dotson

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Sep 28, 2003, 11:38:39 PM9/28/03
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A 4 amp panel is probably around 65 watts. Do you think a 60 watt
light bulb would provide enough heat for your purpose? It might
depending upon how well insulated the trailer is.

Doug

"Survival Bill" <bill...@shaw.ca> wrote in message
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Joe Fischer

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Sep 29, 2003, 1:07:23 AM9/29/03
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"Survival Bill" <bill...@shaw.ca> wrote:

>I would like to use a spare solar panel to run a 12 volt car heater would a
>4 amp panel be enough and just a fuse in between or will running something
>like this directly off a panel damage the panel?

Is it a heater, or a heater fan you are talking about?
I don't think I have ever seen a 12 volt heater on a car,
some cars have heater fans or squirrel cage blowers that
draw 4 to 10 amps.

A resistance heater would have to draw a lot
more than 4 amps to put out useful heat. Most small
110 volt heaters with fans are 700 watts or more, and
at 12 volts 700 watts would be more than 60 amps.

Joe Fischer

John Phillips

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Sep 29, 2003, 6:36:56 PM9/29/03
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On Mon, 29 Sep 2003 00:10:03 GMT, "Survival Bill" <bill...@shaw.ca>
wrote:

>I would like to use a spare solar panel to run a 12 volt car heater would a
>4 amp panel be enough and just a fuse in between or will running something
>like this directly off a panel damage the panel? I was thinking of using
>this to heat the trailer during the day to keep things from freezing during
>the day when I am out....

Survival Bill,

I have looked at your photo that shows that the solar panel(s) is
located on the roof of your trailer. I am sure you realize that the
solar panel will also absorb energy that would otherwise also heat the
trailer. Depending on the relative insulation level of the trailer and
a lot of other factors, it might be prudent to do nothing unless you
move the solar panel so it does not shade the trailer.

Regards,

John Phillips

Roland Mösl

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Oct 1, 2003, 3:47:01 AM10/1/03
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> I would like to use a spare solar panel to run a 12 volt car heater would
a
> 4 amp panel be enough and just a fuse in between or will running something
> like this directly off a panel damage the panel? I was thinking of using
> this to heat the trailer during the day to keep things from freezing
during
> the day when I am out....

Do You start Your car in the 4th gear?

A 12 V Buffer battery is used to take energy from a solar panel
near the maximum power point.

Without buffer battery, it can happen that the
solar panel is delivering 4.5 Ampere at 8 V,
instead of 4 Ampere at 12 V reducing much the
efficiency of the system.

At a small cloud, maybe
1 A at 2 V instead of 0.9 A at 12 V.


--
Roland Mösl
http://www.pege.org Clear targets for a confused civilization
http://web-design-suite.com Web Design starts at the search engine

Lynn Coffelt

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Oct 1, 2003, 6:38:04 PM10/1/03
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"Roland Mösl" <fou...@pege.org> wrote in message
news:3f7a868a$0$21264$91ce...@newsreader01.highway.telekom.at...

> > I would like to use a spare solar panel to run a 12 volt car heater
would
> a
> > 4 amp panel be enough and just a fuse in between or will running
something
> > like this directly off a panel damage the panel? I was thinking of using
> > this to heat the trailer during the day to keep things from freezing
> during
> > the day when I am out....
>
> Do You start Your car in the 4th gear?
>
> A 12 V Buffer battery is used to take energy from a solar panel
> near the maximum power point.
>
> Without buffer battery, it can happen that the
> solar panel is delivering 4.5 Ampere at 8 V,
> instead of 4 Ampere at 12 V reducing much the
> efficiency of the system.
>
> At a small cloud, maybe
> 1 A at 2 V instead of 0.9 A at 12 V.
>
>
> --
> Roland Mösl

Many conventional DC motors that are "stalled" because of insufficient
voltge/current will overheat since there is no "reverse voltage/current"
generated by the motor itself. This "reverse" generation prevents a normally
operating conventional DC motor from drawing excessive current. (Yes, I
realize the current drops when panel illumination decreases, but what
current is available will be generating heat, not work)
Lynn


JAG

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Oct 9, 2003, 11:30:12 PM10/9/03
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If you have sun you have heat. Build a large heat exchanger to circulate
liquid from the hot sun heated roof (glass enclosed sections of copper tubes
on black surface) then move "pump" the heated liquid to a coil inside the
living space, very effecient energy exchange. Use solar electricity to run
the pump and fan to push the heat out from the inside the living space coil.
If there is not enough sun to run the pump and fan then there is likely not
enough heat/solar energy anyway.

This way if you have sun you have heat. Sounds like a cool project, all pun
intended!

Hope this helps,

mike


"Survival Bill" <bill...@shaw.ca> wrote in message
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