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| willbanks 2006-09-21, 5:25 pm |
| I need a little help. I have for years thought about building a solar
thermal AC unit (ammonia-water system) but I lived farther north so the
trouble of building it to only use it a month or two wasn't worth it. Now
that I've moved to southern costal GA I think it would. Now that I'm
getting serious about it I can't find any 'hard' plans nor even much info.
The first unit I'd like to build would be in the 3 ton/36,000BTU range.
With a 5+ ton unit to be built for a larger home in the future. The
instructor from the local community college has offered to give me a hand
but all of his studies has been in conventional AC.
Can anyone give me some input or at least point me toward some good info?
thanx
| |
| Joe Fischer 2006-09-21, 5:25 pm |
| On Thu, "willbanks" <richwillbanks@tds.net> wrote:
>I need a little help. I have for years thought about building a solar
>thermal AC unit (ammonia-water system) but I lived farther north so the
>trouble of building it to only use it a month or two wasn't worth it. Now
>that I've moved to southern costal GA I think it would. Now that I'm
>getting serious about it I can't find any 'hard' plans nor even much info.
You need to study the safety issues and dangers
carefully before undertaking this project.
There are two types, much the same, and both
use dangerous and/or toxic chemicals.
One is;
http://en.wikipedia.org/wiki/Gas-ab...on_refrigerator
and the other is the Einstein;
http://en.wikipedia.org/wiki/Einstein_refrigerator
>The first unit I'd like to build would be in the 3 ton/36,000BTU range.
>With a 5+ ton unit to be built for a larger home in the future. The
>instructor from the local community college has offered to give me a hand
>but all of his studies has been in conventional AC.
I remember something about a lot of these being
removed from commercial buildings some time ago,
and there may be some used ones available, but with
the recent high price of copper, the ones not in use
may have been scrapped.
I think concentrating mirrors and trackers would
be needed to heat oil, it would seem that 400 F would
be hot enough to make a unit work.
If it were me, I would want to have all radiator/
heat exchanger coils in the house to each be a continuous
tube in one piece with no connections in the house.
I had a Servel gas refrigerator in the 1950s, but
I don't know which process it used.
There may be other thermal units that don't
use such doubly dangerous gases, it might pay to
check.
In freon A/Cs the hard part is evacuating
the system to a deep enough vacuum to boil any
water off and remove it, but in these two processes,
water is used.
It might be better to try to buy one.
Joe Fischer
| |
| willbanks 2006-09-21, 8:26 pm |
| >>I need a little help. I have for years thought about building a solar
>
> You need to study the safety issues and dangers
> carefully before undertaking this project.
>
> There are two types, much the same, and both
> use dangerous and/or toxic chemicals.
Been there done that ammonia is bad but not that bad in the open where the
unit would be located. On the up side its REAL easy to tell if you have a
leak 
>
> I remember something about a lot of these being
> removed from commercial buildings some time ago,
my guesses would be: 1) it was cheaper to replace them with new high
efficiency compressor units. 2) the legal libility, someone a mile away
gets a slight smell of NH3 and they claim damage and sue.
> and there may be some used ones available, but with
> the recent high price of copper, the ones not in use
> may have been scrapped.
Humm. . .copper and ammonia don't really get along do they. All the info I
have seen calls for steel, perferably stainless.
> I think concentrating mirrors and trackers would
> be needed to heat oil, it would seem that 400 F would
> be hot enough to make a unit work.
No oil involved. NH3 and water is all. You can build a 'one way' unit to
make ice with common pluming parts and a parabolic trough mirror. I have
plans for a unit like that that will make either 10 lbs or 10 kg of ice per
day.
I even have diagrams showing an old "Icy Ball" which was sold years ago
which was basically two balls on a pipe. You heated one to drive the
ammonia into the other then set it so that ball was inside a insolated box.
Was said to keep the box cool for 24 hrs on a charge.
> If it were me, I would want to have all radiator/
> heat exchanger coils in the house to each be a continuous
> tube in one piece with no connections in the house.
I haven't made up my mind about getting the coldness into the house. I'm
leaning towards a heat exchanger to cool water and using a large radiator
and fan to do the house cooling. That would mean that any leaks would
either be outside or contained in the closed loop of the cooling system's
water.
> I had a Servel gas refrigerator in the 1950s, but
> I don't know which process it used.
> There may be other thermal units that don't
> use such doubly dangerous gases, it might pay to
> check.
Most likely NH3.
> In freon A/Cs the hard part is evacuating
> the system to a deep enough vacuum to boil any
> water off and remove it, but in these two processes,
> water is used.
I'm thinking the hardest part of this is going to be getting the anhydrous
ammonia. I'll only need small amount and that's just what the meth makers
use.
> It might be better to try to buy one.
That's no fun. May as well tell people to buy a solar oven 90% of the fun
is making it
| |
| Morris Dovey 2006-09-21, 8:26 pm |
| willbanks (in huFQg.1094$5i7.781@newsreading01.news.tds.net) said:
| I'm thinking the hardest part of this is going to be getting the
| anhydrous ammonia. I'll only need small amount and that's just
| what the meth makers use.
Hint: It's also what a lot of farmers use. If you're prepared to show
that you have a legitimate alternative-energy project, I'd guess that
you'd win a lot of cooperation from farmers, at a farm co-op, and
(perhaps) even at the USDA extension office in your county...
--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto
| |
| Joe Fischer 2006-09-21, 8:26 pm |
| On Thu, "willbanks" <richwillbanks@tds.net> wrote:
>..........
>I even have diagrams showing an old "Icy Ball" which was sold years ago
>which was basically two balls on a pipe. You heated one to drive the
>ammonia into the other then set it so that ball was inside a insolated box.
>Was said to keep the box cool for 24 hrs on a charge.
I thought maybe the inventors names, etc. would
help find more detailed plans on the net.
The drawing at the top of the Einstein page can
be enlarged, then a download of a hires image is offered,
but I don't know if that will help, it is just a schematic
drawing and probably doesn't even resemble the real
plumbing.
The servel was heavy, and big, but had a very
small flame, more like a bunsen burner.
I know it was heavy, I took the unit out in
one piece and carried the thing to a 3rd floor attic
apartment, and back down 4 months later, and
used it for 5 years.
Sorry I don't know of any real plans or
any kits being sold.
Joe Fischer
| |
| willbanks 2006-09-22, 3:25 am |
| > | I'm thinking the hardest part of this is going to be getting the
> | anhydrous ammonia. I'll only need small amount and that's just
> | what the meth makers use.
>
> Hint: It's also what a lot of farmers use. If you're prepared to show
> that you have a legitimate alternative-energy project, I'd guess that
> you'd win a lot of cooperation from farmers, at a farm co-op, and
> (perhaps) even at the USDA extension office in your county...
Not a lot of farming down here. I haven't gotten to the point of trying to
find a supply much less seeing how many hoops I might have to jump through
to be able to buy it.
| |
| willbanks 2006-09-22, 3:25 am |
| >>I even have diagrams showing an old "Icy Ball" which was sold years ago
>
> I thought maybe the inventors names, etc. would
> help find more detailed plans on the net.
I'll check into it.
> The drawing at the top of the Einstein page can
> be enlarged, then a download of a hires image is offered,
> but I don't know if that will help, it is just a schematic
> drawing and probably doesn't even resemble the real
> plumbing.
>
> The servel was heavy, and big, but had a very
> small flame, more like a bunsen burner.
> I know it was heavy, I took the unit out in
> one piece and carried the thing to a 3rd floor attic
> apartment, and back down 4 months later, and
> used it for 5 years.
A simple 'charge-use-charge' system isn't that much of a problem. Almost
any one who can weld can make one of those. The trick comes into keeping
the stuff flowing. I have seen rough drawings of systems which seem to use
nothing more than heat and gravity to run the run. But this isn't really
the type of project I want to start w/o more than rough drawings. The parts
could get real expensive in a hurry if its going to involved a lot of
stainless steel welding.
| |
| RamRod Sword of Baal 2006-09-22, 1:25 pm |
|
"willbanks" <richwillbanks@tds.net> wrote in message
news:NbJQg.1131$5i7.872@newsreading01.news.tds.net...
>
>
> I'll check into it.
>
>
> A simple 'charge-use-charge' system isn't that much of a problem. Almost
> any one who can weld can make one of those. The trick comes into keeping
> the stuff flowing. I have seen rough drawings of systems which seem to
> use nothing more than heat and gravity to run the run. But this isn't
> really the type of project I want to start w/o more than rough drawings.
> The parts could get real expensive in a hurry if its going to involved a
> lot of stainless steel welding.
Ammonia is very efficient when used in a compressor type system, but not
when used in an absorption type system.
Ammonia is a wonderful refrigerant, but not used in air conditioning
systems, because it is poisonous, it burns and it explodes. The idea of
waking up in a room full of ammonia vapour is something that would terrify
anyone who has worked with ammonia.
When ammonia get in contact with moisture, such as the eyes or lungs, it
turns into a very caustic type substance, causing a great deal of damage.
Absorption air conditioning systems use water as the refrigerant, and
lithium bromide as the absorber. They can be quite temperamental
systems.They require the system to work under a fairly deep vacuum.
Absorption refrigeration is not very efficient compared to compressor type
of refrigeration.
FYI
http://www.fredonia.edu/facilitiesm...frigChiller.htm
| |
| no spam 2006-09-22, 5:25 pm |
| > Ammonia is very efficient when used in a compressor type system, but not
> when used in an absorption type system.
I'm not worried too much about the efficiency because I'd be using 'free'
energy, i.e. solar.
> Ammonia is a wonderful refrigerant, but not used in air conditioning
> systems, because it is poisonous, it burns and it explodes. The idea of
> waking up in a room full of ammonia vapour is something that would terrify
> anyone who has worked with ammonia.
>
> When ammonia get in contact with moisture, such as the eyes or lungs, it
> turns into a very caustic type substance, causing a great deal of damage.
Which is why I'm leaning towards a water heat exchanger. All the ammonia
would be well away from the house and no way for a major leak to reach the
inside. You'd have to have the ammonia leak into the cooling water than the
contaminated water to leak into the house. By that time you'd have a very
diluted ammonia.
I have worked with some 'nasty' chemicals before, things that cause death in
seconds w/ a drop the size of a pin head on the skin, so I have a very
healthy respect for those little warning lables ;)
> Absorption air conditioning systems use water as the refrigerant, and
> lithium bromide as the absorber. They can be quite temperamental
> systems.They require the system to work under a fairly deep vacuum.
Which puts it well outside the home builder range. NH3 on the other hand is
1940's tech so any fairly well equipped modern shop should be able to handle
it.
>
> Absorption refrigeration is not very efficient compared to compressor type
> of refrigeration.
Again not on my list of problems because even if it is only 50% efficient
I'm still saving money because I'm using free solar power and not high
priced electric to run it.
| |
|
| It is my understanding that most single stage units like Yazaki use lithium bromide
and have a COP of around 0.5, but only require maybe 180F to operate. The dual stage
units can use ammonia and have a COP closer to 1.0, but require higher temperatures
to operate.
"no spam" <no@spam.net> wrote in message news:%jWQg.1189$5i7.241@newsreading01.news.tds.net...
> Ammonia is very efficient when used in a compressor type system, but not
> when used in an absorption type system.
I'm not worried too much about the efficiency because I'd be using 'free'
energy, i.e. solar.
> Ammonia is a wonderful refrigerant, but not used in air conditioning
> systems, because it is poisonous, it burns and it explodes. The idea of
> waking up in a room full of ammonia vapour is something that would terrify
> anyone who has worked with ammonia.
>
> When ammonia get in contact with moisture, such as the eyes or lungs, it
> turns into a very caustic type substance, causing a great deal of damage.
Which is why I'm leaning towards a water heat exchanger. All the ammonia
would be well away from the house and no way for a major leak to reach the
inside. You'd have to have the ammonia leak into the cooling water than the
contaminated water to leak into the house. By that time you'd have a very
diluted ammonia.
I have worked with some 'nasty' chemicals before, things that cause death in
seconds w/ a drop the size of a pin head on the skin, so I have a very
healthy respect for those little warning lables ;)
> Absorption air conditioning systems use water as the refrigerant, and
> lithium bromide as the absorber. They can be quite temperamental
> systems.They require the system to work under a fairly deep vacuum.
Which puts it well outside the home builder range. NH3 on the other hand is
1940's tech so any fairly well equipped modern shop should be able to handle
it.
>
> Absorption refrigeration is not very efficient compared to compressor type
> of refrigeration.
Again not on my list of problems because even if it is only 50% efficient
I'm still saving money because I'm using free solar power and not high
priced electric to run it.
| |
|
| Any refrigeration supply house will sell you a cylinder. They may
have to order it if it's a small outfit.
On Thu, 21 Sep 2006 23:45:17 GMT, "willbanks" <richwillbanks@tds.net>
wrote:
>
>Been there done that ammonia is bad but not that bad in the open where the
>unit would be located. On the up side its REAL easy to tell if you have a
>leak
>
>
>
>my guesses would be: 1) it was cheaper to replace them with new high
>efficiency compressor units. 2) the legal libility, someone a mile away
>gets a slight smell of NH3 and they claim damage and sue.
>
>
>
>Humm. . .copper and ammonia don't really get along do they. All the info I
>have seen calls for steel, perferably stainless.
>
>
>
>No oil involved. NH3 and water is all. You can build a 'one way' unit to
>make ice with common pluming parts and a parabolic trough mirror. I have
>plans for a unit like that that will make either 10 lbs or 10 kg of ice per
>day.
>
>I even have diagrams showing an old "Icy Ball" which was sold years ago
>which was basically two balls on a pipe. You heated one to drive the
>ammonia into the other then set it so that ball was inside a insolated box.
>Was said to keep the box cool for 24 hrs on a charge.
>
>
>
>I haven't made up my mind about getting the coldness into the house. I'm
>leaning towards a heat exchanger to cool water and using a large radiator
>and fan to do the house cooling. That would mean that any leaks would
>either be outside or contained in the closed loop of the cooling system's
>water.
>
>
>Most likely NH3.
>
>
>
>I'm thinking the hardest part of this is going to be getting the anhydrous
>ammonia. I'll only need small amount and that's just what the meth makers
>use.
>
>
>
>That's no fun. May as well tell people to buy a solar oven 90% of the fun
>is making it
>
| |
|
| willbanks wrote:
> I need a little help. I have for years thought about building a solar
> thermal AC unit (ammonia-water system) but I lived farther north so the
> trouble of building it to only use it a month or two wasn't worth it. Now
> that I've moved to southern costal GA I think it would. Now that I'm
> getting serious about it I can't find any 'hard' plans nor even much info.
>
> The first unit I'd like to build would be in the 3 ton/36,000BTU range.
> With a 5+ ton unit to be built for a larger home in the future. The
> instructor from the local community college has offered to give me a hand
> but all of his studies has been in conventional AC.
>
> Can anyone give me some input or at least point me toward some good info?
>
> thanx
I say you're on the right track Will, solar cooling is the ultimate
challenge. When I was in college I studied the Servel ammonia
refrigerator system with the intent of driving it off of a solar
concentrator system. I got as far as understanding the basic principle
and here's what I remember:
The key to the system is the boiling point of your working liquid. In
the Servel, the ammonia was heated in a reservoir vessel. There was a
small (say =BC" ) tube that allowed the warm ammonia gas (boils at a
low temperature) to travel up to the top of the unit. The gaseous
ammonia then spirals down a cooling coil (say =BD"). As the ammonia
cools some of it turns back into a liquid. The liquid trickles down
into the mid section of the unit into the absorber coil (say =BC" ).
Since liquid ammonia boils at -28F any heat energy inside the fridge
will cause a small portion of the liquid to turn back into a gas.
It's this State change of a substance (ammonia in this case) that
requires an input in energy to transition from a liquid to a gas
that's responsible for the cooling action.
I have to admit, I built a working steel model of this system that cost
about $300 in 1982, got a gallon of ammonia but never had the guts to
fire it up. The ammonia was pretty scary stuff. What we need is a safer
working fluid with the right properties.
Good luck on your project,
Doug Sherman
US Davis, Physics 1983
| |
| John Ladasky 2006-09-25, 8:25 pm |
|
willbanks wrote:
> I need a little help. I have for years thought about building a solar
> thermal AC unit (ammonia-water system) but I lived farther north so the
> trouble of building it to only use it a month or two wasn't worth it. Now
> that I've moved to southern costal GA I think it would. Now that I'm
> getting serious about it I can't find any 'hard' plans nor even much info.
>
> The first unit I'd like to build would be in the 3 ton/36,000BTU range.
> With a 5+ ton unit to be built for a larger home in the future. The
> instructor from the local community college has offered to give me a hand
> but all of his studies has been in conventional AC.
>
> Can anyone give me some input or at least point me toward some good info?
>
> thanx
Why would you want to work with ammonia, which is volatile, and toxic?
A geothermal exchange system can provide you with air conditioning,
without any hazardous working fluid.
http://geoexchange.com/
The only moving parts in a geoexchange system are two fans. Because
you use the soil as a heat sink, you also have a lot of leverage. It's
not uncommon to obtain the same cooling effect with a 1,000 W
geoechange system as you would with 2,500 W of active cooling. So,
could probably even run a geoexchange system with solar PV, and achieve
efficiencies in the same range as your ammonia-based solar thermal
cooler.
A quick look at this site...
http://www.griffin.uga.edu/aemn/
..=2E.suggests that deep soil temperatures, which are about the same as
average year-round air termperatures, are around 68=BAF in your area.
That's quite workable for air conditioning.
+-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=
=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-+
| Ladasky Home Solar, Inc.: blowing sunshine up your |
| power grid since March 24, 2005. Fiat lux! |
+-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=
=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-+
| Uptime Downtime kWh generated kWh consumed |
| 549 days 6.5 hours 10445 10343 |
+-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=
=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-+
| |
| John Ladasky 2006-09-25, 8:25 pm |
| willbanks wrote:
> I need a little help. I have for years thought about building a solar
> thermal AC unit (ammonia-water system) but I lived farther north so the
> trouble of building it to only use it a month or two wasn't worth it. Now
> that I've moved to southern costal GA I think it would. Now that I'm
> getting serious about it I can't find any 'hard' plans nor even much info.
> The first unit I'd like to build would be in the 3 ton/36,000BTU range.
> With a 5+ ton unit to be built for a larger home in the future. The
> instructor from the local community college has offered to give me a hand
> but all of his studies has been in conventional AC.
> Can anyone give me some input or at least point me toward some good info?
> thanx
Why would you want to work with ammonia, which is volatile, and toxic?
A geothermal exchange system can provide you with air conditioning,
without any hazardous working fluid.
http://geoexchange.com/
The only moving parts in a geoexchange system are two fans. Because
you use the soil as a heat sink, you also have a lot of leverage. It's
not uncommon to obtain the same cooling effect with a 1,000 W
geoexchange system as you would with 2,500 W of active cooling. So,
you could probably even run a geoexchange system with solar PV, and
still achieve efficiencies in the same range as your ammonia-based
solar thermal cooler.
Having the ability to operate on electricity would also allow you the
option to continue to cool the house after dark. This is not so
important where I live in California, because the humidity is always
low here, when the weather is hot. But I lived in Baltimore, Maryland
for a while. The heat and humidity can continue well into the night
there. I can only imagine that it's worse in Georgia.
A quick look at this site...
http://www.griffin.uga.edu/aemn/
..=2E.suggests that deep soil temperatures, which are about the same as
average year-round air temperatures, are around 68=BAF in your area.
That's quite workable for air conditioning.
+-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=
=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-+
| Ladasky Home Solar, Inc.: blowing sunshine up your |
| power grid since March 24, 2005. Fiat lux! |
+-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=
=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-+
| Uptime Downtime kWh generated kWh consumed |
| 549 days 6.5 hours 10445 10343 |
+-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=
=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-+
| |
|
| willbanks wrote:
Just to give you another direction.
Look into the desicant driers, it's relatively easy to to dry the
desicant with solar heat and then you add moisture for evaporative
cooling. A lot less trouble than an absorption cooler.
Jeff
> I need a little help. I have for years thought about building a solar
> thermal AC unit (ammonia-water system) but I lived farther north so the
> trouble of building it to only use it a month or two wasn't worth it. Now
> that I've moved to southern costal GA I think it would. Now that I'm
> getting serious about it I can't find any 'hard' plans nor even much info.
>
> The first unit I'd like to build would be in the 3 ton/36,000BTU range.
> With a 5+ ton unit to be built for a larger home in the future. The
> instructor from the local community college has offered to give me a hand
> but all of his studies has been in conventional AC.
>
> Can anyone give me some input or at least point me toward some good info?
>
> thanx
>
>
| |
| no spam 2006-09-26, 1:25 pm |
|
"John Ladasky" <ladasky@my-deja.com> wrote in message
news:1159224350.868221.321260@i42g2000cwa.googlegroups.com...
>
>Why would you want to work with ammonia, which is volatile, and toxic?
Because its a proven technoligy, fairly cheap and isn't all that dangerous.
>A geothermal exchange system can provide you with air conditioning,
>without any hazardous working fluid.
I have also thought of 'geo' by using an open loop ground water (i.e. water
from a well) or closed loop. But they require pumps which requires fair
amounts of power. They also require a lot of work and money. Drilling a
well or burying the water line loops.
>The only moving parts in a geoexchange system are two fans. Because
How do you do that? I don't see a thermal syphen working on a home cooling
scale.
>ould probably even run a geoexchange system with solar PV, and achieve
>efficiencies in the same range as your ammonia-based solar thermal
Maybe, which I would doubt, but you are looking at a much larger money out
put.
| |
| no spam 2006-09-26, 1:25 pm |
| > Just to give you another direction.
>
> Look into the desicant driers, it's relatively easy to to dry the
> desicant with solar heat and then you add moisture for evaporative
> cooling. A lot less trouble than an absorption cooler.
Hum. . .hadn't thought about that. Any numbers on how well it would work.
Also with just a quick brain storm I can see several problems to over come.
The desicant would have to be moved from a drying chamber to an evaporation
chamber. Then you get into what liquid to use. Water pops to mind but how
much cooling could you get with water? Using any other liquid would require
you to recover the liquid.
But it does give me something to think about.
| |
| Joe Fischer 2006-09-26, 1:25 pm |
| On Tue, "no spam" <no@spam.net> wrote:
>Also with just a quick brain storm I can see several problems to over come.
>The desicant would have to be moved from a drying chamber to an evaporation
>chamber. Then you get into what liquid to use. Water pops to mind but how
>much cooling could you get with water? Using any other liquid would require
>you to recover the liquid.
Evaporating water on the outside of a heat exchanger
to cool the water inside should work well.
Just fasten a burlap cloth on the sides of the heat
exchanger, and it will be cooled to about 55 or 60 degrees,
even in the high temperatures there.
While you are at it, maybe build some freon engines
using direct sun on the boiler and the condenser with the
burlap and evaporating water for the cool side.
I don't know how much stirling engines run, or
if they are easy to build, but free energy while the sun
shines would be nice.
Joe Fischer
| |
|
| no spam wrote:
>
>
> Hum. . .hadn't thought about that. Any numbers on how well it would work.
Google came up with this and others, I can't find what I was reading before:
<URL:
http://www.cibse.org/pdfs/desiccant...nt%20cooling%22 />
Apparently a COP of > 1. Note that that PDF gives a lot of equations and
details. I think is pretty good because the more cooling you need, the
more solar energy you have to drive the cycle. Very high humidity
locations will require a second dehumidify cycle and will have lower COPs.
>
> Also with just a quick brain storm I can see several problems to over come.
> The desicant would have to be moved from a drying chamber to an evaporation
> chamber.
Dehumidifiers can work several ways but it seems to me the easiest for
solar would be to have a rotating disc of desicant, part of the disc is
in the "drier" and part is in the inlet to the cooler. The disc slowly
turns...
Then you get into what liquid to use. Water pops to mind but how
> much cooling could you get with water?
Water. What a wonderfull thermal material it is!
Using any other liquid would require
> you to recover the liquid.
>
> But it does give me something to think about.
I'm out of cooling season here (mostly) but I'll want to do this later.
Let me know if you go this route, I really can't see another for a home
builder.
Jeff
| |
| FukUSpamer@fukspamer.com 2006-09-26, 8:25 pm |
| The ammonia was pretty scary stuff. What we need is a safer
working fluid with the right properties.
Good luck on your project,
Doug Sherman
US Davis, Physics 1983
Could you elaborate more why it is scary stuff ? and any precautions ?
Sorry I admit I am an XXX in Chemistry ..... :-)
| |
| Anthony Matonak 2006-09-27, 3:25 am |
| FukUSpamer@fukspamer.com wrote:
> The ammonia was pretty scary stuff. What we need is a safer
> working fluid with the right properties.
>
> Could you elaborate more why it is scary stuff ? and any precautions ?
> Sorry I admit I am an XXX in Chemistry ..... :-)
Ammonia is toxic at fairly low levels. Even if it doesn't kill you
outright, it can burn your lungs, eyes, skin and so forth. The whole
"it can kill or maim you for life" is the scary part.
Anthony
| |
|
|
"Anthony Matonak" <anthonym40@nothing.like.comcast.net> wrote in message news:AdadnTwSROUleYTYnZ2dnUVZ_sqdnZ2d@comcast.com...
> FukUSpamer@fukspamer.com wrote:
>
> Ammonia is toxic at fairly low levels. Even if it doesn't kill you
> outright, it can burn your lungs, eyes, skin and so forth. The whole
> "it can kill or maim you for life" is the scary part.
>
> Anthony
Considering you can use a dessicant system or other less harmful
absorbants for cooling, I would take the safer route.
| |
|
| In article <AdadnTwSROUleYTYnZ2dnUVZ_sqdnZ2d@comcast.com>,
Anthony Matonak <anthonym40@nothing.like.comcast.net> wrote:
> FukUSpamer@fukspamer.com wrote:
>
> Ammonia is toxic at fairly low levels. Even if it doesn't kill you
> outright, it can burn your lungs, eyes, skin and so forth. The whole
> "it can kill or maim you for life" is the scary part.
>
> Anthony
Ammonia is only scary, if you don't know how to deal with it.
We have TONS of it around here in our Cold Storage, and it
isn't scary here. Yes, it can get out, just like the Magic
Smoke, can get out of wires, but the idea is to design a system
that keeps the "Scary Stuff" where it belongs, inside the pipes.
If your a Greenie EnviorWhaco, CFC's are a lot more scary than
ammonia. CFC's are causing the Earth to END, and SOON.... if your
a "Greenie EnviorWhaco"......... and if not, well CFC's were
eliminated, so DuPont could charge 500% more for Refrigerant.....
| |
| no spam 2006-09-27, 1:25 pm |
| >> The ammonia was pretty scary stuff. What we need is a safer
>
> Ammonia is toxic at fairly low levels. Even if it doesn't kill you
> outright, it can burn your lungs, eyes, skin and so forth. The whole
> "it can kill or maim you for life" is the scary part.
So can a lot of things like riding in a car. In both cases you just have to
use a little common sense and a few readily available, inexpensive
protection apparatus. Working with NH3 outdoors and a way to flood the area
with water spray, such as a sprinkler, adds to your safety level.
| |
| no spam 2006-09-27, 1:25 pm |
| >>> The ammonia was pretty scary stuff. What we need is a safer
>
> Considering you can use a dessicant system or other less harmful
> absorbants for cooling, I would take the safer route.
You have any data showing that a dessicant system works? Ammonia systems
have decades of working systems.
| |
| no spam 2006-09-27, 5:25 pm |
| >> > Could you elaborate more why it is scary stuff ? and any precautions ?
>
> Ammonia is only scary, if you don't know how to deal with it.
Finally someone else who has common sense!
| |
|
| no spam wrote:
>
>
> Finally someone else who has common sense!
>
>
>
>
We have different ideas about common sense!
Common sense, in this case, is in designing something that can actually
be built. You want to sketch out a water ammonia solar cooling system
that the OP can build?
Jeff
| |
| Joe Fischer 2006-09-27, 5:25 pm |
| On Wed, 27 Sep 2006 18:38:20 GMT, "no spam" <no@spam.net> wrote:
>
>Finally someone else who has common sense!
>
>
It does have a distinctive smell, so if you smell it,
hold your breath and run like hell.
It might even pay to practice to see how long
breathe can be held and how far one can run in that time. :-)
Joe Fischer
| |
| daestrom 2006-09-27, 5:25 pm |
|
"You" <You@shadow.orgs> wrote in message
news:You-A0F7AD.09202927092006@netnews.att.net...
> In article <AdadnTwSROUleYTYnZ2dnUVZ_sqdnZ2d@comcast.com>,
> Anthony Matonak <anthonym40@nothing.like.comcast.net> wrote:
>
>
> Ammonia is only scary, if you don't know how to deal with it.
> We have TONS of it around here in our Cold Storage, and it
> isn't scary here.
Since you work with a lot of it, I suspect you've had some safety training
on the subject. Maybe have an eye-wash or emergency shower station nearby
in case you get some on you. And the folks that service it are competent
about fittings/connections/etc... and proper leak testing. The local water
treatment folks here have 'tons' of the stuff sitting outside the treatment
plant. A FEMA drill a couple years back centered around an 'accident' with
one of the casks. Many fire departments also 'drill' for such accidents
with railroad cars of the stuff in various forms. Perparation and training
means the hazard can be contained and handled correctly.
It's 'scary' for those that don't know what their doing (or only *think*
they know what they're doing). Kind of like 'rocket science' or 'nuclear
power'. Scary in the wrong hands, relatively safe in the right hands.
daestrom
| |
|
| There is a university in Austria that has designed a system that works
very well at lower high-side temps. On their web site they have the
whole diagrams, and almost a construction plan, not quite. It uses
regular steel tubing, and the idea was to cool third world countries
using solar heat. With their system you don't need concentrators, it
works fairly efficiently at regular solar temperatures. If I
remember, they added another recirculating loop in the system and it
greatly increased efficiency at say 160 degrees F. I think they had
construction plans you could get off their site. Sorry, I don't
remember the name but it may have been a Technical University.
As I worked on a ship I asked the engineers about it and they said it
was a system anyone with familiarity with tools and welding could
build easily.
I think I got the info in this newsgroup several years ago.
I think it was an improvement on the Servel system with two gasses,
but they added an additional Hydrogen loop that greatly increased
efficiency at lower temps... Maybe someone else here will remember...
On 25 Sep 2006 14:33:40 -0700, "doug" <dougs@nmtv.com> wrote:
>willbanks wrote:
>
>I say you're on the right track Will, solar cooling is the ultimate
>challenge. When I was in college I studied the Servel ammonia
>refrigerator system with the intent of driving it off of a solar
>concentrator system. I got as far as understanding the basic principle
>and here's what I remember:
>
>The key to the system is the boiling point of your working liquid. In
>the Servel, the ammonia was heated in a reservoir vessel. There was a
>small (say ¼" ) tube that allowed the warm ammonia gas (boils at a
>low temperature) to travel up to the top of the unit. The gaseous
>ammonia then spirals down a cooling coil (say ½"). As the ammonia
>cools some of it turns back into a liquid. The liquid trickles down
>into the mid section of the unit into the absorber coil (say ¼" ).
>Since liquid ammonia boils at -28F any heat energy inside the fridge
>will cause a small portion of the liquid to turn back into a gas.
>It's this State change of a substance (ammonia in this case) that
>requires an input in energy to transition from a liquid to a gas
>that's responsible for the cooling action.
>
>I have to admit, I built a working steel model of this system that cost
>about $300 in 1982, got a gallon of ammonia but never had the guts to
>fire it up. The ammonia was pretty scary stuff. What we need is a safer
>working fluid with the right properties.
>
>Good luck on your project,
>
>Doug Sherman
>US Davis, Physics 1983
| |
|
| Turn a hose with nozzle in a fan spray and it will suck up the
ammonia like a sponge, that's how they clean a space with a leak.
On Wed, 27 Sep 2006 15:39:52 -0400, Joe Fischer
<joe@bigscreencomputers.com> wrote:
>On Wed, 27 Sep 2006 18:38:20 GMT, "no spam" <no@spam.net> wrote:
>
>
> It does have a distinctive smell, so if you smell it,
>hold your breath and run like hell.
>
> It might even pay to practice to see how long
>breathe can be held and how far one can run in that time. :-)
>
>Joe Fischer
| |
| Merlin-7 KI4ILB 2006-09-27, 8:25 pm |
| Well back to the subject and the question asked.
Why not run a pipe down the center of some kind of tube with a concave
reflector at the bottom focased on your pipe containing the ammonia and a
clear top. If possible you could put a vacume in the tube for added
insulation.
That should give you a good boiler for your refrigerant.
If you work it right, you could use gravity and the fact that heat rises to
do away with anykind of pump.
You would have to play with the size of the solar tubes to get the results
needed but I see no reason why it would not work.
It would work the same way many refrigerators in campers work.You would
just replace the heat source, instead of a flame you would use solar on a
bigger scale...
Joe
| |
| Anthony Matonak 2006-09-27, 8:25 pm |
| daestrom wrote:
> "You" <You@shadow.orgs> wrote in message
....
....[color=darkred]
> It's 'scary' for those that don't know what their doing (or only *think*
> they know what they're doing). Kind of like 'rocket science' or
> 'nuclear power'. Scary in the wrong hands, relatively safe in the right
> hands.
You will note that few homes have either rocket or nuclear
fuel on the property. Nor would they be permitted by whatever
authorities regulate these things.
Anthony
| |
| daestrom 2006-09-27, 8:25 pm |
|
"Anthony Matonak" <anthonym40@nothing.like.comcast.net> wrote in message
news:SdKdnXEIQ_5NhYbYnZ2dnUVZ_s2dnZ2d@comcast.com...
> daestrom wrote:
> ...
> ...
>
> You will note that few homes have either rocket or nuclear
> fuel on the property. Nor would they be permitted by whatever
> authorities regulate these things.
>
That is to say, 'John Q. Public' is the 'wrong hands'. I would say the same
thing about ammonia. John Q Public is not knowledgable enough about it to
be tinkering around with it.
daestrom
| |
|
|
|
|
| no spam 2006-09-28, 9:25 am |
| >>>>>Could you elaborate more why it is scary stuff ? and any precautions ?
> We have different ideas about common sense!
>
> Common sense, in this case, is in designing something that can actually be
> built. You want to sketch out a water ammonia solar cooling system that
> the OP can build?
>
Seeing as how ammonia coolers were being built in the mid 1900's building
them today in any modern home shop would be no problem. At the bottom of
this msg are a couple of websites showing how to make 'intermittent cycle'
coolers to make ice. The second requires nothing more than welding. Which
you could have done in almost any town in the US for a few bucks.
One problem I'm having is finding a plan with enough details on a continuous
cycle cooler's set up. Mainly how to regulate the flow of the liquid NH3
into the evaporator and how to make sure the flow in one way.
http://www.thesustainablevillage.co...rise/display/14
www.homepower.com/files/solarice.pdf
| |
| no spam 2006-09-28, 9:25 am |
| >> It's 'scary' for those that don't know what their doing (or only *think*
>
> You will note that few homes have either rocket or nuclear
> fuel on the property. Nor would they be permitted by whatever
> authorities regulate these things.
They may not have nuke fuel laying around but most homes have everything
needed to make rocket fuel. And if they don't have it on hand a trip to
Wally World would take care of it. All you need is a little know how and a
little work.
Heck the first 'rocket fuel' was nothing more than black power. I made that
in the shop at home when I was a kid many years ago
| |
| no spam 2006-09-28, 9:25 am |
| >>> It's 'scary' for those that don't know what their doing (or only *think*
>
> That is to say, 'John Q. Public' is the 'wrong hands'. I would say the
> same thing about ammonia. John Q Public is not knowledgable enough about
> it to be tinkering around with it.
And the stories of burning lungs, blindness and death keeps them from doing
so. You have to remember that every spring hundreds if not thousands of
tanks of ammonia are on the roads and in the farm fields across the US. Now
when was the last time you heard so a NH3 death in the US?
| |
|
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| Anthony Matonak 2006-09-28, 9:25 am |
| no spam wrote:
>
> Been there, done that and no useful info on the actual construction. The
> basic concept is simple as the solar ice link you list shows. The problem
> is getting the info to make a continuous cycle system.
Do you need a continuous cycle system?
Imagine, if you will, that you have an extremely well insulated garden
shed, R100 or something, and inside it you have tanks of water built so
they don't crack if the water turns to ice. Somewhere in this shed,
either wrapped around the tanks or using an air radiator, are loops of
water pipe filled with brine or water and antifreeze. This is the brine
that gets cooled by the solar ice maker and the "cold" gets stored as
ice inside the shed. Another loop of pipe with brine (or perhaps the
same one) is used to provide cooling to your home by melting the ice.
Two advantages of this are that you can still get cooling when the sun
goes down, assuming you've got enough ice, and you've got temperatures
low enough to keep a fridge cool.
Anthony
| |
| no spam 2006-09-28, 1:25 pm |
| >>>>Can anyone give me some input or at least point me toward some good
>
> Do you need a continuous cycle system?
>
> Imagine, if you will, that you have an extremely well insulated garden
> shed, R100 or something, and inside it you have tanks of water built so
> they don't crack if the water turns to ice. Somewhere in this shed,
> either wrapped around the tanks or using an air radiator, are loops of
> water pipe filled with brine or water and antifreeze. This is the brine
> that gets cooled by the solar ice maker and the "cold" gets stored as
> ice inside the shed. Another loop of pipe with brine (or perhaps the
> same one) is used to provide cooling to your home by melting the ice.
>
> Two advantages of this are that you can still get cooling when the sun
> goes down, assuming you've got enough ice, and you've got temperatures
> low enough to keep a fridge cool.
Might work but I'd think it take a much larger unit. After all I'd have to
have enough BTU not only to replace the ice I use for cooling but to make
more ice. Also more money; shed, ice container and such.
>
> Anthony
| |
| Anthony Matonak 2006-09-28, 1:25 pm |
| no spam wrote:
>
> Might work but I'd think it take a much larger unit. After all I'd have to
> have enough BTU not only to replace the ice I use for cooling but to make
> more ice. Also more money; shed, ice container and such.
Air conditioning takes a lot of energy. No matter what process you use,
continuous or intermittent, you'll still need that large amount of
energy. This will require large collectors and other such parts. The
only way to avoid that is to use every trick in the book to keep your
air conditioning needs small.
Anthony
| |
| Joe Fischer 2006-09-29, 3:25 am |
| On Thu, "no spam" <no@spam.net> wrote:
[color=darkred]
>Might work but I'd think it take a much larger unit. After all I'd have to
>have enough BTU not only to replace the ice I use for cooling but to make
>more ice. Also more money; shed, ice container and such.
Those might equal about a one ton unit if a radiator
and fan were use for A/C.
I listed a back issue of Solar Engineering Magazine
on ebay that shows what was being done almost 30 years ago.
http://cgi.ebay.com/May-1978-Issue-...1QQcmdZViewItem
Joe Fischer
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