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Jamul

I feel like there may be some potential here in these tanks. I have a row of tanks with 15,000 gallons of water or 120k pounds. (Photo in my diary) Yesterday they got up to 70F and this morning they were 62f while outside temp was 41F, which is about 3F below average.We get about 10 light to moderate frost days per year. Starting to learn the math on what size and type of hoop house would most benefit from this storage? I would like to stay above 50-55F almost always. I am allowed up to 3,000 square feet without permits. Just learning the math, it be nice to hear any input from those knowledgeable. They have a pretty direct side aspect connection to the south. I am at latitude 32. The idea is to bring competitive products to farmers markets to supplement what grows outdoors here in the winter... and maybe do fish for the house.

Is there anyone who would be willing to discuss the variables on a thread?

1/28/2011 12:44:17 PM

Jamul

The photo is pending approval by BP.com.

1/28/2011 12:50:09 PM

I have spent a lot of time the last 2 years researching various methods of heating high tunnels. My area is much colder in winter.

I suggest you consider getting a "hydronic unit heater" for the green house,,,low volume pump hooked to a thermostat to circulate the water from the tanks through that heater you should be able to keep temps in the range you seek.

You also can get info from other gh growers in your area that have green houses set up. Also find heating contractors that can steer you in the right direction.

http://www.modine.com/v2portal/page/portal/hvac/hvacGreenhouseDefault/hvac_com/greenhouse/level_3_content2_039.htm#ggviewer-offsite-nav-9777216

1/29/2011 8:20:04 AM

Jamul

Unkadan,Your challenge is much bigger than mine for sure. My sister and her family live in Stoughton.

Unless I am out to lunch, these tanks I have release 1,200,000 Btu's going from 70F to 60F an another 1,200,000 from 60F-50F. I guess I need to verify that. I was hoping that this had enough potential in and of itself, given the good solar situation and mild winters. I was thinking or adding heat to the fish pool water if necessary and depending on the breed of fish. Gas heaters are not out of the question but would require permits and infrastructure. Since we are able to grow a lot of things outside in the winter, spending any money is tough to get back. I am starting to get to know some produce growers and a few have greenhouses so that is a good suggestion to talk with them.

1/29/2011 12:29:58 PM

Stoughton is balmy,,,lol

I'm sure with what you are wanting to do the thermal storage provided by those tanks is plenty,,,converting it to heat where you need it is the trick. I've talked to growers that use underground hydronic tubing run in zones. That would be overkill for your temps.

The heater I sent the link for uses just that preheated water you already have. I have found these here for under $200 used, with pump and items to hookup you could be up and running for less than $500, installed if you find the right heating man. (Assuming you already had electricity supplied to the gh.)

1/29/2011 4:32:58 PM

Jamul

I thought(am hoping) that by having the tanks inside the gh. and perhaps some fans that this would distribute the energy from the water tanks.It might also help them get warmer,storing more heat, in the day while keeping daytime air temps more manageable. Getting things used is a good idea. I'll remember that. I could convert those heaters to LP gas and put a tank & regulator if necessary. Electricity is doable.

There is also potential with building a "lean-to" type structure against the south and west sides of the tanks which are about 13 feet tall and insulating the north sides of the tanks and maybe the tops too, forcing the Btu's to mostly exit on one side. I am going to build something small and temporary, while it is still cold enough to experiment with. Maybe try to start and early melon plant with the tanks and an attached cold frame only, or with soil heater cables.

1/29/2011 8:55:50 PM

a few points:

1.That link is "just" a liquid to air heat exchanger,,think of a car radiator and fan,,only here you are blowing the heat from you tank water into the desired space

2.Those tanks will use alot of space in your gh, it's all about square footage production when growing in one.

3.Consider a separate structure for the tanks, then move the warmer air to the gh when needed. Simple fans and ducts could serve the purpose.

1/29/2011 9:17:51 PM

Jamul

Thanks for airing this out with me.

I see what you are saying now and have considered the space problem. The lean-to sort of addresses the space issue and is cheaper to build but wouldn't take advantage of the cooling effect when I wanted it.

Didn't dwell much on the separate structure idea but there is a lot of potential there too.Very good suggestion. Maybe get the water even hotter with a glass south wall and insulated north wall.I have been saving sliding glass doors and can get more free or cheap.

Back to the idea of having it inside a large gh, or as an insulated lean-to, white washing it in the summer could be worth something for cooling. The cool tanks plus shade cloth...HMMM.

Maybe there is some potential with creating north and south "zones" at different climates by an intermediate wall with the tanks as a divider.

1/29/2011 9:37:22 PM

Jamul

I hope I am not throwing to many curves or being too dense.
Realizing here that the glass solar collector and every thing could be overkill. Maybe heat 10 green houses or melt the tanks! Always good to know ones options :).

1/29/2011 10:31:22 PM