Propane powered AC?

If you have a steady water supply available... coolerado.

My next door neighbor growing up had a NG-powered home AC unit. It worked, but was more expensive to run than electricity powered units (which is saying something, given NG was much less expensive at the time).

I wonder how long a 20 lb propane bottle would last if used to run a trailer AC unit. :)

With all the problems I read about gas fridges, I would rather see a move to electric, rather than from it. For low power draw, I'd like to see Truma's VeGA propane fuel cell hit the US market. With that quietly charging the batteries and compensating for a compressor fridge's amp draw, there is no need to bother with an absorption fridge.

Of course, if more than that amount of wattage is needed, there is always a LP gas generator.

wa8yxm wrote:
Ok, a small house fridge draws say 100 watts... A small Window Air conditioner perhaps a thousand.. Think about this

I have seen freezers chilled by Absorption cooling units but they are very large, and very very very well insulated, the Absorption cooling takes up to 24 hours to cool your RV Fridge.. how long do you think it would take to cool your RV which has far less insulation... A cooling unit big enough to do a decent job would be as big as the RV if not bigger.

OP - research how absorption refrigerators work, LOL.

And.... ever wonder why there isn't a propane (or natural gas) connection at the campground pedestals??..:S

...

Many years ago, *home* AC units were offered powered by natural gas instead of electricity.
No doubt a (less than) bright idea by the gas company.
(Propane would obviously be an alternate to the nat gas)

Had a friend who "bought in" to that one!..:R
A choice right up there with left-handed monkey wrenches for right-handed monkeys.
Probably some kind of incentive (by/from the gas co) involved.

MAJOR "PITA"!! - MAJOR mistake!

NEVER did what it was supposed to do - as in "cooling" properly.

I never saw the unit, never checked on how it operated - but heard all the *MANY* tales of woe!..:(

He went back to AC powered A/C - and chalked it off to a really, really bad decision (and $$ loss)..:S

.

holstein13 wrote:
Just get a solar powered Air Conditioner: http://www.lennox.com/products/solar-ready/

Wouldn't work in a camper but, it looks like it would be good in a home.

Just get a solar powered Air Conditioner: http://www.lennox.com/products/solar-ready/

For comparison, an RV frig is about 4000BTUH. So think how large a Gas/absorption unit would be for an 15,000BTUH A/C unit....plus HEAVY.

Years ago, Bryant offered a home gas/absorption A/C unit, and it was rather large.

As for absorption A/C units in commercial applications, there are still making them as water chillers and are also used in industrial applications that have waste heat to drive them.

Battery banks with an inverter to run one or two 15,000BTUH A/C units would be heavy as well as expensive. Just look at how many batteries you have to have to run a 600 Watt refrigerator.

Next issue is the solar cells to keep batteries charge for long term use.

One roof top unit will need about 1800 Watts. On 12 VDC, they will need 150 amps , not allowing for starting and efficiency loss in the inverter.

You best bet is a generator to power the standard roof tops.

Ken

I was mainly thinking about boondocking and Class B's and Truck Campers where space is limited and the Onan gens are so noisy. If the AC was on propane(like the fridge); just seems like it would be ideal.

Using currently available roof units; anyone take a guess as to how much battery would need to be onboard and how many potential hours of run time could be had from the roof mount AC? Looks like they pull 15 amps:

http://www.coastdistribution.com/PDF/Coleman%20Product%20Page.pdf

In the 70's, there was a combination roof-air/generator available which was propane fueled.

DrewE wrote:
I suppose one practical approach (more practical than a whole-RV absorption air conditioner, at least) might be to modify a truck reefer unit by replacing the little diesel engine with a propane-fueled engine. It wouldn't have much if any advantage over a propane fueled generator and traditional electric air conditioner except possibly being a bit more efficient overall (due to avoiding the conversion from mechanical to electrical energy and back again).

Most interesting! I don't know how efficient generators are but I would guess no more than 80%, so this approach using a propane engine to directly power the AC should be significantly more efficient than using a generator. The engine in either case is only about 25% efficient.

The downside is that you wouldn't have an electric AC to use at powered campsites, and would have a lot of noise on the roof.