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TFOGGER
08-05-2015, 12:20
I'm looking for 2 or maybe 3 plastic barrels to fill with water to act as thermal mass in the new greenhouse I'm building (pics to follow in another thread), preferably in black. The basic idea is to store the heat generated during the day and allow the barrels to radiate heat at night in the winter to reduce the amount of heating required. We currently have 2x55 gallon steel barrels that are pretty much at the end of their service life (rusting through), and want to replace them with similar, only more rust resistant. These do not need to be food grade, but do need to be clean and non-hazardous. Does anyone have a good source?

RCCrawler
08-05-2015, 13:43
Could you fit a 235gallon schutz tote?

Irving
08-05-2015, 13:46
Could you full them with rocks instead of water so you don't have to fight 110 gallons of frozen water every morning when the house is warming up?

izzy
08-05-2015, 14:00
I've actually used stones before as well as water to do this. Darker the stone the better. I lined the pathways of my garden with the stones and used smaller amounts of water. I had good luck with partially buried 5 gallon buckets. There is also a thing called wall-o-water that you can put around individual plants.

TFOGGER
08-05-2015, 14:35
Could you fit a 235gallon schutz tote?

We could, but it would eat into the growing space, as the greenhouse is rather small (7'x8')


Could you full them with rocks instead of water so you don't have to fight 110 gallons of frozen water every morning when the house is warming up?

The water never gets that cold. Currently, the 55 gal drums we're using sit in the corners of the greenhouse and act as supports for one of the shelves for the plants. On a sunny day, they might get up to 80 degrees or so (keeping the greenhouse from overheating), and we never let the temperature in the greenhouse get below 48 degrees at night (the tropical houseplants and tomatoes don't like it). We've been using electric oil radiators for heat, and the barrels cut our peak winter electric bill significantly.

Great-Kazoo
08-05-2015, 15:28
http://www.homedepot.com/b/Building-Materials-Roofing-Gutters-Roofing-Roof-Panels/N-5yc1vZaq4r/Ntk-Extended/Ntt-corrugated+plastic+sheet?Ntx=mode+matchpartialmax&NCNI-5

We used the smoked tinted units. You make wall - frame around the structure at an angle /I . Have a few places to allow open & closing to adjust temp. It's utilizing sunlight to keep the area heated. If you consider small (5gal) water buckets against the structure with the smoked fiberglass panels built around those. You might stay freeze free in the winter. What's nice about the 5gal buckets. IF one freezes it's easy to replace AND thaw out vs a 55 gal unit.

Lurch
08-05-2015, 19:25
I can get you 30 gal plastic drums in white

Great-Kazoo
08-05-2015, 19:36
I can get you 30 gal plastic drums in white

Prepare to have a full PM inbox by 19:45- 20:00 tops.

















PM sent.

TFOGGER
08-05-2015, 21:26
http://www.homedepot.com/b/Building-Materials-Roofing-Gutters-Roofing-Roof-Panels/N-5yc1vZaq4r/Ntk-Extended/Ntt-corrugated+plastic+sheet?Ntx=mode+matchpartialmax&NCNI-5

We used the smoked tinted units. You make wall - frame around the structure at an angle /I . Have a few places to allow open & closing to adjust temp. It's utilizing sunlight to keep the area heated. If you consider small (5gal) water buckets against the structure with the smoked fiberglass panels built around those. You might stay freeze free in the winter. What's nice about the 5gal buckets. IF one freezes it's easy to replace AND thaw out vs a 55 gal unit.

The walls on the new one are going to be 8mm twin wall polycarbonate, the roof is 10mm triple wall. It should give us an average R rating of 1.9, a huge improvement. The old greenhouse was single wall polycarbonate (Lexan) about .75 mm.

Great-Kazoo
08-05-2015, 21:41
The walls on the new one are going to be 8mm twin wall polycarbonate, the roof is 10mm triple wall. It should give us an average R rating of 1.9, a huge improvement. The old greenhouse was single wall polycarbonate (Lexan) about .75 mm.

I'm talking about doing polycarbonate along the base , like a flower box. This provides more heat / solar.

spongejosh
08-05-2015, 22:29
I see the white and blue plastic ones on CL all the time for under $25. Just need some black krylon.

http://denver.craigslist.org/grq/5154560622.html

meatman
08-07-2015, 06:25
PM me. I can get you a few 55 gal blue, black, or white.

rbeau30
08-07-2015, 06:55
I have a blue plastic one. I haven't opened it in a while may need to be rinsed out You are welcome to it. I thought I wanted it, but I don't have room for it.

TFOGGER
08-07-2015, 07:27
Thanks guys, I'll be in touch!

Great-Kazoo
08-07-2015, 10:36
Thanks guys, I'll be in touch!

If it wasn't too cost prohibitive. Mixing windshield washer fluid, or non-toxic animal safe[er] anti-freeze with the water, might minimize the winter freezing issue.

meatman
08-07-2015, 10:44
If it wasn't too cost prohibitive. Mixing windshield washer fluid, or non-toxic animal safe[er] anti-freeze with the water, might minimize the winter freezing issue.

They're using supplemental heat so the plants and water barrels will never go below freezing.

We use some of the barrels for watering in the greenhouse (with a barrel pump) during the winter since the garden hose isn't hooked up out there.

izzy
08-07-2015, 10:52
I think anti freeze might actually make the area colder. Water can only get so hot and so cold. Once it's frozen you actually want to keep that temperature floor.

TFOGGER
08-07-2015, 10:55
They're using supplemental heat so the plants and water barrels will never go below freezing.

We use some of the barrels for watering in the greenhouse (with a barrel pump) during the winter since the garden hose isn't hooked up out there.

Yup. The barrels are simply there to store the "free" heat during the day and release it at night.