Air Conditioned Shop?

[eclipsme]

lol! That's a fact.

Harvey

[Steve]

Mac;

Thanks for the details - yes it does help to understand the context.

We're in the middle of moving into this house, and I'm working on getting the workshop set up - it's great to be able to start from scratch and design the layout and set up a real dust collection system this time. I've also ordered an air filtration system (the $189 Grizzly) to hang in there

The house is three years old, and seems to be very well insulated - even the attached garage, in which I'm using one of the three bays as my principal workshop area. The garage ceiling is 11 ft, and the whole garage is dry-walled on the inside, with stucco on the exterior walls and concrete tile on the roof.

We've had some pretty hot weather already, but this garage seems to be slow to get hot inside - the only day it was unbearably hot in there was when the outside temp hit 108 F earlier this week. On cooler days (in the 90's) last weekend I was able to work on setting up the shop with a large oscillating fan to keep me from getting overheated.

But once I get back into some serious guitar-building, I'm gonna need to air-condition this space, and a mini-split system seems to be the way to go. I tried a 12000-BTU window-type in the old garage, and it was just not up to the job - it could do no better than to maintain the temp in the low-to-mid 80's.

--Steve

[Max]

I have an evaporative cooler that works fairly well. (dry climate, El Paso) I like the exhaust effect; it blows the dust out the slightly opened o'head door.

Max

[mac davis]

Cool... I was afraid that I was boring you to death... lol

Something else that I should have mentioned... I'll be adding an exhaust fan high on one wall, since I can't vent through a concrete roof...

If you can get the warm air out of the ceiling space before you turn on the AC, it's much more efficient..

Right now I'm using a small desk-size fan, in an 11" wide board that a window closes on... I had the fan on a shelf at the bottom of the window but the air blowing out was too cool, so I moved it to the top of the window and the exhaust is warmer... Still, the top of the window is about 3 1/2 feet from the ceiling, so I'll bore a hole in the block wall and mount a fan there with pretty louvers and all.. *g*

Enjoy the shop, Steve.... This is my 5th or 6th shop, and the first one that wasn't in a garage, shared by water heater, washer & dryer, family junque, etc... What a luxury!

mac

Please remove splinters before emailing

[mac davis]

Good to know... We brought down a very nice ceiling fan with lights, remote, etc.... Being the wrong color/style, the wife wouldn't allow it in the house and is in a box someplace... I think I'll try it!

My recliner was the wrong color, too.. a major blow to an ol' fart like me... Finally found a large striped blanket at a local vendor that she liked, so I got to keep my "newly decorated" recliner... lol

mac

Please remove splinters before emailing

[Steve]

Sounds like a great idea - I'm going to look into that too.

I DO have to share space with the water heater, a refreigerator & freezer, and some household storage. And a car, since my wife will be parking her car in there once we get everything organized. And the city has this ordinance that requires that space for vehicles be maintained when operating a home business, so I can't permanently expand and take over the entire garage.

Thanks again for the info & advice!

--Steve

[John B]

G'day Steve, I'd agree with Mac's thinking on an exhaust fan up high. I have a corrugated iron shed, about 40 x 24 with 9' walls and a pitch height of

12'. Putting a whirly bird "wind powered exhaust fan" at the very top of the roof helped heaps. The walls are now insulated and the roof about half way and I have an evaporative air con in the wall. Humidity is not a problem in Kalgoorlie. however temperatures range from

-4 to 48c.

all the best John

[J T]

Sun, Jul 8, 2007, 11:24am (EDT-1) [e-mail] (Morris=A0Dovey) doth sayeth: Going as fast as I can on a completely solar-powered air conditioner - perhaps by next summer or the summer after...

Did a google. Seems like it could be done already. I didn't check the sites, but a lot of them gave that impressio.

Some years back found an article on a solar boiler, with parabolic mirrors. Ran down to a steam engine. One thing about a steam engine, ten don't need to e too huge o put ut a lot of power (torque). Solar boiler, steam engine, truck refrigeration uit, or air conditioner. Should work. Or plant a batch of trees so your shop is shaded.

JOAT I do things I don't know how to do, so that I might learn how to do them. - Picasso

[Morris Dovey]

J T wrote: | Sun, Jul 8, 2007, 11:24am (EDT-1) [e-mail] (Morris Dovey) | doth sayeth: | Going as fast as I can on a completely solar-powered air | conditioner - perhaps by next summer or the summer after... | | Did a google. Seems like it could be done already. I didn't | check the sites, but a lot of them gave that impressio. | | Some years back found an article on a solar boiler, with | parabolic mirrors. Ran down to a steam engine. One thing about a | steam engine, ten don't need to e too huge o put ut a lot of power | (torque). Solar boiler, steam engine, truck refrigeration uit, or | air conditioner. Should work. Or plant a batch of trees so your | shop is shaded.

Shade works well. So does designing a building to be cool.

My personal preference runs toward simplicity and a minimum of moving parts.

I'm planning to drive a fluidyne (a Stirling engine using water pistons) with heated air from a passive flat panel collector, then use the kinetic energy from that engine to drive a second fluidyne which (I'm hoping) will develop a hot side and a cold side. The cold side will be used to chill water to be circulated by third fluidyne pump. Total moving parts: 5 (the first three of which are water, and the last two are the "flappers" in a pair of check valves. None of it will be as warm as the boiling point of water.

It does seem as though someone should already have done exactly this, but I haven't been able to find a trace.

There has been a fair amount of development with high temperature mechanical systems, but such systems are inherently expensive. The solution I'm after doesn't add up to anything more than heated air causing columns of water to oscillate in tubing.

Only the thermally-driven engine (two out of the three fluidynes) is working at this point. We've scaled it up to use 4" schedule 40 PVC pipe - and are only getting about a two-inch "stroke" (should be between 15" and 18"), but that's a lot better than the initial 1/8" stroke it started with. Cooling power will depend on solar collector area, and the general rule of thumb there is about a kW per square meter of panel.

It probably won't be wonderfully efficient, but it should be considerably more efficient than a high temperature system. Also, by using flat panel collectors it should be able to operate in hazy and overcast weather. I'm not sure how the efficiency stacks up against a conventional air-conditioner - but since the sun is providing all the power needed, it shouldn't have /any/ operating cost.

Best of all, none of the parts can wear out.

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[Charley]

Morris and Joat,

Have you looked into using an "absorption refrigeration" system to make your solar powered air conditioner? A small heat source makes them work quite well. Do you remember the old Servel refrigerators that ran on propane ? (also some newer camping refrigerators that are multi-powered use this principle) No moving mechanical parts and great efficiency. In fact, many of the 60-80 year old Servels are still in use.

Charley

[Morris Dovey]

Charley wrote: | Morris and Joat, | | Have you looked into using an "absorption refrigeration" system to | make your solar powered air conditioner? A small heat source makes | them work quite well. Do you remember the old Servel refrigerators | that ran on propane ? (also some newer camping refrigerators that | are multi-powered use this principle) No moving mechanical parts | and great efficiency. In fact, many of the 60-80 year old Servels | are still in use.

I've seen some of the older units used in camping trailers and done a bit of researching on the Internet. They work well for small volumes, but look considerably more expensive to produce than what I'm working on. They also appear to require significantly higher temperatures, which for solar applications means a concentrating collector (a parabolic trough or dish) whose performance would be poor if the skies were hazy or overcast. I like 'em, but they don't appear to offer a good solution to the whole house or shop cooling problem.

I had an interesting discussion this morning about providing solar heat for stock tanks (if you're not a farm person, these are galvanized watering troughs for livestock - a small tank holds something like 75 gallons). I'd been looking for a way to circulate hot air _downward_ from a solar heating panel to a heat exchange tube near the bottom of a stock tank and had been pricing photovoltaic panels and small blowers - and had just about decided that a workable combination was just too expensive. This morning I asked my compadre if he thought the solar pump we've been working on to pump water could be used to pump air...

He opined that as long as we oriented the check valves so that gravity would make them "normally closed", we could pump air as easily as we can pump water. It's one of those cases where I'd knocked myself out looking for a solution that was right under my nose all along...

This stuff /does/ keep life interesting!

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[Morris Dovey]

| Only the thermally-driven engine (two out of the three fluidynes) is | working at this point. We've scaled it up to use 4" schedule 40 PVC | pipe - and are only getting about a two-inch "stroke" (should be | between 15" and 18"), but that's a lot better than the initial 1/8" | stroke it started with.

I just posted a photo of this kluge to ABPW. When I get time, I'll add it to the web page at the link below.

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[Jim Behning]

[Morris Dovey]

Jim Behning wrote: | Could they not uses a solar panel to heat water with a recirculating | pump powered by solar electric panel?

Yuppers. The problem is that this configuration is too expensive - a suitable DC motor for the blower and a photovoltaic panel capable of producing enough current is fairly spendy. My farming prospect nixed the use of anti-freeze; hence my decision to pump air.

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[Jim Behning]

I would agree with the farmer based on how destructive my horses can be around the water trough. Keep us posted on the project as it sounds interesting. I only suffer a few days where it does not get above freezing so your project is just interesting to me.

[The Happy Drunk]

Hmmmmm my shed has no A/C .... then again it has no heating either. During summer I open the doors , during winter I put a coat on.

Would love Airconditioning but it think some insulation wll be first on the list. That is, after I convince the MOFAW to allow some money out of the account ;-) __

Cheers The Happy Drunk

[Allen Roy]

Well next time your in town, stop and say Hi.