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if ammonia is unsafe just use LIBR

i think solar absorbers are the way to go

i often wonder why they do not do it in automoboles where you have the free generator/engine????????????

I am going to build a solar powered A/C system eventually

That is what I set out to do: build a solar powered absorption chiller. But in working towards that goal I realized that I could more cost effectively spend time by first reducing my need for cooling.

I have some hydronic solar collector panels installed (120 square feet) and have two more (80 square feet) waiting for my pipefitter attentions.

But before I get to that I am replacing my roof with very high SRI standing seam metal roofing - in Solar White. I chose the aluminum substrate which lasts pretty much forever and the coating reflects 83% of the sun's heat back out and away from the house. Out in the bright sun it is cool to the touch.

Plus, I replaced all the siding with styrofoam-filled vinyl over 1" foil faced foam board. And I am adding extensive insulation to the attic spaces.

At present I have six tons of A/C running here and I'd like to get to needing only two tons. At that point I think the solar heat powered absorption system can be done cost effectively.

Well; unless I count my own nearly priceless time. <g>

PHM
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Originally Posted by few2many

Has there been any work on a solar powered amonia absorbtion hvac system?
I know they are used for rv refrgerators and small scale stuff. Also, I realize that for a home sized hvac, it would be pretty large. It takes a little heat from a propane flame to remove heat from the evap. This could probably be supplimented with solar heat.

Originally Posted by few2many

just put it outside in some far corner of the yard and run glycol lines.

It will likely take up your entire yard, unless you have multiple acres. Take a look at how big a unit that can only make a few ice cubes is. There are some plans for that around the internet. Multiply by 10 then figure in the added cost of the pump, glycol etc. energy to pump the glycol etc. What are you saving? Better to put the effort into a really efficient DX or a evaporative water cooled condenser.

Unsafe? but... would it really be much worse than an ammonia leak confined inside of a house, as in a gas fired freezer? if I had to pick, I think I would take my chances with the outside heat pump leaking. I dunno.

just put it outside in some far corner of the yard and run glycol lines.

Originally Posted by bob_scheel

There is another reason it is not done. Cost. A solar ammonia system big enough to cool a typical house would be so expensive that if you put the 5-7% interest it would cost to finance it against the utility bill from a standard DX package you would be losing money. Ditto if you paid cash. You could make enough in interest by investing the money to more than pay your electric bill. Your investment would never pay for itself. Plus how many people like looking at a big industrial scale mess of mirrors and pipes in there backyard. OR in their neighbors back yard. Add in the possibility of having to evacuate the neighborhood if there is a leak and your insurance company would have kittens.

You are correct. Though quite safe, it's still possibility of leaking. Safety, i think, is the most common factor when someone thinks about ammonia system.

Here is article in Ashrae Journal - "Ammonia Future", it talks a lot about Ammonia as a trend in using refrigerant.

Solar Powered Absorption

There is solar absorbers out there. One of the companies I consult for is Yazaki Energy. They make water fired, gas fired and solar powered absorbers. We use water as the refrigerant mixed with a lithium bromide solution.

I agree Bob, that interest on the initial cost is greater than the energy bill of a dx aircon. But would that still be true if the cost of the energy doubled? Well, er, yes, since by the time the energy cost doubles, the cost of the materials would probably double also. Cry'ing shame too, cause we need a solution. We just can not afford to continue this expensive cooling habit. Especially in the far South.

I wonder if passive thermal techniques using materials that are dirt cheap are cost effective. Earth as a thermal barrier does more than insulate; it delays and attenuates thermal gradients. But this is too far off topic. Somebody else on this forum already pointed out that you can save more money in the envelope design stage than you can in the hvac equipment selection phase, although both are important.

Originally Posted by few2many

Has there been any work on a solar powered amonia absorbtion hvac system?
I know they are used for rv refrgerators and small scale stuff. Also, I realize that for a home sized hvac, it would be pretty large. It takes a little heat from a propane flame to remove heat from the evap. This could probably be supplimented with solar heat.

There is another reason it is not done. Cost. A solar ammonia system big enough to cool a typical house would be so expensive that if you put the 5-7% interest it would cost to finance it against the utility bill from a standard DX package you would be losing money. Ditto if you paid cash. You could make enough in interest by investing the money to more than pay your electric bill. Your investment would never pay for itself. Plus how many people like looking at a big industrial scale mess of mirrors and pipes in there backyard. OR in their neighbors back yard. Add in the possibility of having to evacuate the neighborhood if there is a leak and your insurance company would have kittens.

check this company out

http://www.robur.com/

Originally Posted by INTECHBILL

Understanding chemistry and make up of refrigerant gases and the bi-products that are associated and produced from their usage will always be difficult for many to understand . One day there will be another common basic refrigerant type such as R-22 that will be LP base and until then we will have many new ones R-410A, R-407c, R-422 .... & ammonia equipment will no longer be applicable due to its dangerous bi-products created by it's separation when used within a system.

INTECHBILL, I'm not trying to be difficult, I'm just trying learn. I don't understand your comments. I've seen a few of your recent posts and I'm not sure when you are being serious or funny.
A. "will always be difficult for many to understand". What do you mean by that? Can you explain refrigerant chemistry, bi-products, and how they relate to ammonia?
B. "due to it's dangerous bi-products created when used within a system". I thought you said "dangerous to the environment".

I've only serviced 50 or so ammonia industrial systems, so I'm definitely not an expert. I'm always wiling to learn.

Originally Posted by INTECHBILL

0.0 = TAX CREDIT
0.0 = GOVERNMENT RESEARCH
0.0 = KNOWLEDGE FOR NEW TECHS
100 % = DEADLY VAPORS FOR THE PUBLIC

Hydrogen cant be bad, its the fuel of the future!!!!Or at least its being sold as such.
And amonia? Is'nt in alot of cleaning poroducts? or has it been regulated out?
What about the water in the system, what happens to that?
I see the ponit of danger, but look at our cars, either petroleum, hydrogen, acids if electric and highly explosive if lipo4.
I actually hadnt realized absorbtion chillers was a mass produced/ manufactured product.
Kinda like the first cars were electric, the first diesels were peanut oil(veg oils) and the stirling engine was invented in the 1800's. All these things are being successfully revisted with modern technology, why not absorbtion?

0.0 = TAX CREDIT
0.0 = GOVERNMENT RESEARCH
0.0 = KNOWLEDGE FOR NEW TECHS
100 % = DEADLY VAPORS FOR THE PUBLIC

Yeah, I considered the amonia inhalation issue, though about using glycol to seperate the living space with the cooler.

0.00 GWP and 0.00 ODP
http://www.ashrae.org/docLib/200622793710_347.pdf

Understanding chemistry and make up of refrigerant gases and the bi-products that are associated and produced from their usage will always be difficult for many to understand . One day there will be another common basic refrigerant type such as R-22 that will be LP base and until then we will have many new ones R-410A, R-407c, R-422 .... & ammonia equipment will no longer be applicable due to its dangerous bi-products created by it's separation when used within a system.

Originally Posted by INTECHBILL

Your writing an area that is old news , out-dated , epa banned and government regulated.. This has been already explored and it was already used for residential a/c , many are still in operation in old resident's in our state. These systems can be deadly and are also bad for the environment, soon they will be replaced in the rv industry with LP systems.

A. EPA banned ?? Please show a link. Ammonia has been the choice for industrial refrigeration for years. Safety hazards....Sure, but banned by EPA?
B. Government regulated....Sure, but all refrigerants are regulated.
C. Bad for the environment? Ammonia has a zero ODP. Please show us a link that ammonia is bad for the environment.

Below is a link for a solar refrigeration system:
http://rds.yahoo.com/_ylt=A0oGki5_Ol...nology.thermal

SCUSOLAR.org has one system that uses solar heating with lithium bromide, an absorption refrigeration cycle. There are others and I'm guessing that there may be more. Solar tax credits, higher oil prices, depleting oil reserves, etc. will only help promote solar refrigeration research.

Your writing an area that is old news , out-dated , epa banned and government regulated.. This has been already explored and it was already used for residential a/c , many are still in operation in old resident's in our state. These systems can be deadly and are also bad for the environment, soon they will be replaced in the rv industry with LP systems.

Amonia absorbtion chillers

Has there been any work on a solar powered amonia absorbtion hvac system?
I know they are used for rv refrgerators and small scale stuff. Also, I realize that for a home sized hvac, it would be pretty large. It takes a little heat from a propane flame to remove heat from the evap. This could probably be supplimented with solar heat.