Building a GH in a Cold Weather Area

[SaraZ]

I'm in WI and would like to build a greenhouse, and not a little one, something of some size. They are like garages I hear, you can never go too big. My issue is, I am in WI and it gets pretty cold, like frigid freezing cold. We run a outside wood burner for the house and are thinking of pouring a concrete slab for the GH and heating the floor to heat it (like we do our garage), just a thought. What would be the most energy efficient way to go for a gh in my area? Are their any used GH in this area or who is a a good supplier?? I know there are a lot of ya in Michigan and other cold areas and I'm hopeing you can lend me some advice and pointers.

THANKS!

[jamesgang]

Sara --- I have been designing a active solar heat sink heating system for my GH project and there is a lot of iinfo on the web --study up on insulation so the cold earth doesn't suck up a lot of the heat energy - also look into PCM (phase change materials) have not found what I am looking for but my ag guys at Ok St U are gone on vacation and hope to have them tell me where to find them PCM products will store more heat than water --up to 10 times in fact....my concept is to get the GH heating system to run off the energy it creates --hot air ---the trick here is to store as much of it as I can for release at nite-- no idea of how big a system to how many square feet --I do feel I will have a gas heater no matter (hopefully on for back up from many cloudy days...ect) James

[dougd]

Low Tech and cheap PCM material include the use of paraffins, fats, and oils.

Lard for example will melt at temperature, retain the heat and solidify when cooled.

Just a hypothetical example. Use old plastic containers with a lid, paint them flat black, and fill with Crisco fat. During the day the suns heat will melt the fat and the heat will be release at night.
The greenhouse must be airtight though.

I have seen passive solar homes with paraffin towers near the windows; same concept.

[Ross]

Originally Posted by dougd

Low Tech and cheap PCM material include the use of paraffins, fats, and oils.

Lard for example will melt at temperature, retain the heat and solidify when cooled.

Just a hypothetical example. Use old plastic containers with a lid, paint them flat black, and fill with Crisco fat. During the day the suns heat will melt the fat and the heat will be release at night.
The greenhouse must be airtight though.

I have seen passive solar homes with paraffin towers near the windows; same concept.

Actually, 55-gallon drums painted black and filled with water will do same thing. Stack them up on north side of greenhouse along wall. Cut out bottoms so they form a column. Fill with water. Only problem in Wisconsin is sun isn't reliable in winter -- more so than Michigan, however not like, say Arizona.

[Ross]

How about this product? Common Wealth Solar Services Maybe costly to start but extremely effecient for heating greenhouses.

[jamesgang]

I agree gentlemen, that these ideas do store some energy--the issue (to me) is more to what will provide a major reduction in cost of operation to the GH--our electric company just raised our base monthly $20 and said they would have to pass on additional increases --making it clear they were not done with future increases-I am researching the idea of an active solar heat sink in the bottom of the GH--supposedly the PCM will store the max amount of heat James

[SaraZ]

Thanks guys, I will for sure look into these ideas. Want to make sure to do it right the first time.