Heating a Greenhouse in the cold, cold cold

The weather is very cold here in the upper Midwest today. The low for tonight is expected to be right around 0F. Boy, as badly as I want a greenhouse, I am sure glad I am not heating one today! I am curious, I am still holding out for a greenhouse and when I do get it I plan to heat it with natural gas. Do most of you use natural gas or another fuel? Do you feel it is efficient? I pay almost $300 a month in electric bills, which includes my home and my grow area in my basement. I have to believe heating a 15' x 30' greenhouse would be more than that.

I can't offer any help Don. Were you able to see Dorsetman's (Geoff) post yesterday in - Members Grow Area ? His greenhouse is below grade by 3 feet. You might want to take a look. It made a lot of sense. It might give you some ideas. Take Care, Rich

We heat our greenhouse with gas and supplement it with electric oil filled 'radiator' style heaters. The electric heaters help keep the gas bill down as it get quite expensive to heat when it gets really cold.

Cheers,
BD

I have thought of sinking it 4 or more feet. I even thought of making it a walkout of my basement with just a few feet above ground, along with a pitched roof. I really like what Geoff did - it makes total sense if it works out for the lot. I also really like the 9' ceiling that Geoff had. Dreaming for now...........but boy would that be something nice to retire to.

Don, I'm in E. Texas, and it is certainly cold here this yr. I do have a small ( 9ft. x15ft. ) which I heat with an electric heater. It is about 1500 watts. However, when it gets really cold, I put a oil burning lamp on the far end to make sure the temp. stays no lower than 55 degrees at night. ( last night it got down to 19 degrees...Brrrr! ) The greenhouse was fine this morning when I checked. Betty :-)

there is hope for me.................

Don; I also have a small northern exposure 8 x 15 greenhouse and with two to three portable electric heaters going at 750 watts each (low settings on all). I can easily keep the Temperature at 62 degrees or above and the electric bill averages about $230.00 to $260.00 a month for everything. I have had a back up propane 10,000 BTU vent less heater in case of power failure. I have not used it in over three years. Lows since December of 16 degrees F. to 30 degrees F. Here I think electric is cheaper than propane. I am not sure about natural gas heating. AL

Ouch! sore subject I just had the propane tank filled $700 worth .
We have an outside wood burner, heat is trapped between the barrel and a metal shell we built it with one of the barrel kits.. works good to take the load off the propane heater also have an electric heater in the back part of the green house it is 12 X 24 I have to look into getting a new propane heater mine is old and not efficient . We hit 0 the other night

I am in central Ohio, maybe a teensy bit warmer than you, but not much, and cloudy all winter. I designed my 14' x 24' greenhouse, built three years ago, with heating as a primary consideration. For that reason, it is attached. I insulated the outside of the foundation, down to the frost line, with one inch thick styro panels, framed it with wood (pressure-treated) instead of metal, and used triple-wall glazing. I cover the inside of the north wall in the winter with roll-type translucent plastic, and have a 50K BTU forced-air gas heater with a 25K southern burner as a backup in case of power or other failure. It is on the west side of the house, and I heat to 55F nights (60F degrees now trying to get an early jump on spring) and usually 70F most days during 'sunlight'. I believe it cost me more to power the lgihts in the three grow-rooms I had before the GH than it does to heat it. The total house gas bill has gone from $60 monthly budget to $85. That means $25 x 12 = $300 TOTAL cost of heating the GH ALL WINTER.

Go with gas, but design with heating costs in mind. And DON'T put it on an existing slab which extends out beyond the GH walls; a friend slapped hers onto an existing patio much larger than the GH and it acts as a heat-sink and sucks out all the heat; she pays over $300 a month to heat it.