Change=opportunity: Solar hot water

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Captain Wheelgun
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Change=opportunity: Solar hot water

Post by Captain Wheelgun »

Background info:
Since 1999, my house, a single-wide manufactured home, has had a large tree on the south side. This has been great for providing shade over my house during the summer.

Change:
That tree began cracking a couple of years ago, with part of it threatening to drop on my roof. Because of this, it was removed a few days ago.

Opportunity:
Now that it is gone, my house has a very clear southern exposure. This has me thinking about ways to use this to my advantage by setting up a solar water heater om my roof. Since my house is all electric, I was thinking that anything that cuts down on electricity usage should help save money.

Have any of you set up or used a solar water heater? Any suggestions? Known pitfalls?
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PawPaw
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Re: Change=opportunity: Solar hot water

Post by PawPaw »

Google "black pipe solar water heater". Lots of things to look at.

We rented a house in Vegas in 2008 for a vacation. The owner had a black pipe solar water heater, basically just 1" black poly pipe coils on the roof that fed into his in-house hot water heater. We had 30 people in the house, with the attendant showering, cooking, washing, etc, and never ran out of hot water. It looked to be a good set-up, Black poly pipe is fairly inexpensive, the plumbing should be relatively simple, I don't really see a downside. With a good southern exposure, you might look into solar electrical panels. The installation is somewhat expensive, but the savings on the electrical bill is phenomenal.
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Weetabix
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Re: Change=opportunity: Solar hot water

Post by Weetabix »

Captain Wheelgun wrote:Any suggestions? Known pitfalls?
Depending on your climate, you might need to protect from freezing. Read up on that if it's an issue.

Make sure the pipe is good for potable water. I haven't worked with it, but I hear PEX is the bomb. HDPE is pretty freeze resistant, but you'd want to butt fuse weld it (long story behind that knowledge).
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Cobar
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Re: Change=opportunity: Solar hot water

Post by Cobar »

My grandfather used one as a pool heater back in the day. It worked well even in Pennsylvania. He just drained the system before the first freeze each year.

I am sure you can find someone online that has a figured out a decent setup to store the hot water for use when the sun is not actively warming it.
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PawPaw
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Re: Change=opportunity: Solar hot water

Post by PawPaw »

Make sure the pipe is good for potable water. I haven't worked with it, but I hear PEX is the bomb. HDPE is pretty freeze resistant, but you'd want to butt fuse weld it (long story behind that knowledge).
PEX is da bomb for lots of things, and I've used it. I even bought some specialty tools for it, BUT, I understand that it's not UV resistant. It's great for burying,it is freeze-resistant, it's wonderful for running through walls, as in conventional plumbing, but you don't want to leave it where the sun can get to it.
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MiddleAgedKen
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Re: Change=opportunity: Solar hot water

Post by MiddleAgedKen »

I've been reading the same about PEX (recently bought a PEX-plumbed house; the manifold is pretty cool).
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JustinR
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Re: Change=opportunity: Solar hot water

Post by JustinR »

The problem with piping water up to the roof...is piping water up to the roof, or so said a professional plumber friend of my father in law. He didn't want to have anything to do with them, because of the extra holes in the side walls of the house, all the extra connections up to the roof, and the damage potential should a connection fail.

With that being said, some of the highest efficiencies being achieved in solar systems are rows of photovoltaic panels with collectors angling the light down to each row, with water tubes immediately below to transfer the heat away for use in hot water systems for the house. I don't know if these are commercially available yet. Personally I'd stick with enough photovoltaic for normal day useage plus charging of a battery bank, but that's just me.
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Darrell
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Re: Change=opportunity: Solar hot water

Post by Darrell »

I have great southern exposure to put solar cells on my roof. Unfortunately, I planted a cottonwood tree in front of the house long ago for shade. It does help keep the front of the house cooler, but damn, it sheds like crazy and makes a mess of the gutters, yard, my car, etc. I'd like to cut it down and be rid of it, but the front of the house gets scorching hot without it. The altitude and climate result in very strong sunlight.

The Air Force Academy put in a huge solar array a few years ago. Looks very impressive from the road. I've heard that the payback time, like 39 years, is longer than the expected lifetime of the array. :roll:
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Weetabix
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Re: Change=opportunity: Solar hot water

Post by Weetabix »

If I recall correctly, it was Joe Vogler who called the cottonwood "an arboreal weed." I've never liked them either.
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Netpackrat
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Re: Change=opportunity: Solar hot water

Post by Netpackrat »

Weetabix wrote:If I recall correctly, it was Joe Vogler who called the cottonwood "an arboreal weed." I've never liked them either.
Joe was right about that and a lot of things. Cottonwood don't burn worth a shit either, so you can't even use them for firewood.
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