How to heat a green small greenhouse.

Artichoke Lover

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I’m looking at purchasing a small relatively cheap greenhouse. Most likely with plastic sides. 10x10 or smaller But I need a way to heat it. I’ll need to keep it 60-70 degrees. Could I use one of the heat lamps I used for my chicks to keep it warm at night?
I’m starting my transplants in it so it only needs heated a few months a year. The rest of the winter I’ll leave it unheated.
 
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We have a 8’x16’ poly carbonate greenhouse that we have been trying to figure out how to efficiently heat a couple months per year. We really have not found anything that heats without running all the time and costing a small fortune. We usually put plastic over the plants at night and run a ceramic heater under them.
 

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it's a physics thing, ambient outside temperature, insulation value of the walls and ceiling vs. how much space you have inside to keep warm, calculate cost of energy, often you may find that it just isn't worth the whole cost v.s. buying items at the store or doing as what i think is the prudent way.

get the poles and covering you need to protect an area, but only use that to give you a few weeks of protection at either end of the season and the rest of the time use the natural energy you get from the sun and grow things outside without and covering at all.

the other approaches involve thermal mass, buring a good part of the structure in the ground, using geothermal energy transfer techniques, rocks, cement, and solar energy to heat and pump water around. nothing wrong with any of that, but while i may dream of such things it often ends up sounding like more work and expense than i want to involve plus i really do like the off season to do other things too. if i had a big underground house and a greenhouse and a heated pool and all the things i might dream about i may also never actually get other things done i like. perhaps too many choices for me for distraction... :)

i just try to be practical and keep things simple. Mom is even more so, she doesn't want to do anything here for improving energy use or solar stuff. i'd enjoy messing with that. at least a hot water heater with just enough solar power to run the pumps and to give us some extra heat here or there. like today would be a perfect example of a day we could perhaps gain a few $ trade-off because the sun is out and has been all day. otherwise very cold.

haha, sorry to run on, thermal mass will be a good friend. :) no, that is not a kind of church service unless you are a physicist. oh, and p.s. it might be discussed more on SS, but i haven't searched there for this kind of topic.
 

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it's a physics thing, ambient outside temperature, insulation value of the walls and ceiling vs. how much space you have inside to keep warm, calculate cost of energy, often you may find that it just isn't worth the whole cost v.s. buying items at the store or doing as what i think is the prudent way.

get the poles and covering you need to protect an area, but only use that to give you a few weeks of protection at either end of the season and the rest of the time use the natural energy you get from the sun and grow things outside without and covering at all.

the other approaches involve thermal mass, buring a good part of the structure in the ground, using geothermal energy transfer techniques, rocks, cement, and solar energy to heat and pump water around. nothing wrong with any of that, but while i may dream of such things it often ends up sounding like more work and expense than i want to involve plus i really do like the off season to do other things too. if i had a big underground house and a greenhouse and a heated pool and all the things i might dream about i may also never actually get other things done i like. perhaps too many choices for me for distraction... :)

i just try to be practical and keep things simple. Mom is even more so, she doesn't want to do anything here for improving energy use or solar stuff. i'd enjoy messing with that. at least a hot water heater with just enough solar power to run the pumps and to give us some extra heat here or there. like today would be a perfect example of a day we could perhaps gain a few $ trade-off because the sun is out and has been all day. otherwise very cold.

haha, sorry to run on, thermal mass will be a good friend. :) no, that is not a kind of church service unless you are a physicist. oh, and p.s. it might be discussed more on SS, but i haven't searched there for this kind of topic.
I’m going to perfectly honest and admit I didn’t understand a word of that other than look on SS.
 

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I’m going to perfectly honest and admit I didn’t understand a word of that other than look on SS.
Since our winter is so short, and summer so hot, and that house so small, I would use removable spacing inside and stretch plastic sheet to create a dead air space in the coldest months. Window film that has a lower emission say 30%, is reflecting 70% of the heat and it is a 2 way street starting from the hot headed to the cold. Usually its used up north to keep a house warm. Down here, never put it on a car. It will probably melt the plastic inside. What are you into that needs a 60f constant?? Thats too low for corn mash??
 
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Since our winter is so short, and summer so hot, and that house so small, I would use removable spacing inside and stretch plastic sheet to create a dead air space in the coldest months. Window film that has a lower emission say 30%, is reflecting 70% of the heat and it is a 2 way street starting from the hot headed to the cold. Usually its used up north to keep a house warm. Down here, never put it on a car. It will probably melt the olastic inside. What are you into that needs a 60f constant?? Thats too low for corn mash??
I’m starting my transplants in there so tomatoes and peppers among other things. I’ve reached the point where I have far to many to keep in the house under grow lights. It will only need heated for 2 maybe 3 months of the year. I realize I forgot to put the rest of the info in my first post and I’ll go back and edit it.
 

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I’m starting my transplants in there so tomatoes and peppers among other things. I’ve reached the point where I have far to many to keep in the house under grow lights. It will only need heated for 2 maybe 3 months of the year.
Let me know if you need some film. I can get it at cost and have it shipped to you. I think that one comes in 60" but maybe 72. I may even have some scraps but I need the panel sizes. I will eyeball the inventory just in case you go that way. Are you sure 50f minimum will not get it done? Why not just use heat mats?
 

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Let me know if you need some film. I can get it at cost and have it shipped to you. I think that one comes in 60" but maybe 72. I may even have some scraps but I need the panel sizes. I will eyeball the inventory just in case you go that way.
Thank you! I think I’m good though. We actually should have a big roll somewhere around here somewhere. We use it on our windows even though we are in the south because whoever put them in did a horrible job.
 

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Thank you! I think I’m good though. We actually should have a big roll somewhere around here somewhere. We use it on our windows even though we are in the south because whoever put them in did a horrible job.
Trust me when I tell you that it is not low emission film. Most film has an emission rate of near 90%, same as glass. See if there is a label and show me the pic and I will find the specs for you.
 

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Trust me when I tell you that it is not low emission film. Most film has an emission rate of near 90%, same as glass. See if there is a label and show me the pic and I will find the specs for you.
I wasn’t able to find the label. And if I’m perfectly honest I’m simply not comfortable giving out my address to someone I haven’t met in person. This isn’t anything personal so please don’t take it that way. I’ve simply had some bad experiences in the past. I really appreciate all the help though!
 
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