Winter Greenhouse Heating Ideas

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Dan Freeman

Minister of Fire
Dec 3, 2021
769
NE PA
www.youtube.com
When 100*C steam changes to 100*C condensate it gives up 2142 btu’s per 1000 g’s. …the original phase change energy transport material - unless the definition is expanded to include wood as an energy transport material with phase change to high temperature plasma, lol.

For comparison, do you know the mass of the 400 btu tiles? Couldn’t find the mass on the web page?

The first sentence is Greek to me.

Mass, not sure.

I do know that Ceres Greenhouses, one of the premier 4 season solar greenhouse companies in the US uses Insolcorp's Phase Change Material in their greenhouses.
 
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EbS-P

Minister of Fire
Jan 19, 2019
4,017
SE North Carolina
I was giving this some thought. The DIY treatment have you. Anyone know the latent of coconut oil. That was the only thing that make to mind. I’m sure there are other materials. I was trying to come up with some better ideas. But wall of water was all I could do. Like a bottle wall.
 
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Dan Freeman

Minister of Fire
Dec 3, 2021
769
NE PA
www.youtube.com
I was giving this some thought. The DIY treatment have you. Anyone know the latent of coconut oil. That was the only thing that make to mind. I’m sure there are other materials. I was trying to come up with some better ideas. But wall of water was all I could do. Like a bottle wall.

Don't know about coconut oil, but that is an interesting idea.

Some PCM's use Paraffin (like the wax in automatic greenhouse window openers). The wax in the automatic opener's piston heats up and liquifies, it expands the piston, and the window opens. At night, the process reverses, but when the liquid paraffin solidifies again, it gives off heat. This is good for both the summer (helps cool) and winter (helps heat).

There are other PCM's but paraffin is the one I am most familiar with. I don't even know what the "ingredients" are in the ones I just ordered. If Ceres Greenhouses uses them, they have to be outstanding, so I ordered them. All I could find on the website was: "Our PCM’s are non-toxic, safe, have high density and are abundant in nature."
 

EbS-P

Minister of Fire
Jan 19, 2019
4,017
SE North Carolina
Don't know about coconut oil, but that is an interesting idea.

Some PCM's use Paraffin (like the wax in automatic greenhouse window openers). The wax in the automatic opener's piston heats up and liquifies, it expands the piston, and the window opens. At night, the process reverses, but when the liquid paraffin solidifies again, it gives off heat. This is good for both the summer (helps cool) and winter (helps heat).

There are other PCM's but paraffin is the one I am most familiar with. I don't even know what the "ingredients" are in the ones I just ordered. If Ceres Greenhouses uses them, they have to be outstanding, so I ordered them. All I could find on the website was: "Our PCM’s are non-toxic, safe, have high density and are abundant in nature."
Soy based wax/oil???
 

RomanW

Member
This brings up a question for me. Is the shape of a greenhouse important or make any difference? I can get the peaked roof style, or the domed style. I assume the only difference is aesthetic, or vertical space along the walls.

Does it negatively or positively affect sunlight within the greenhouse at all? Which one would you choose if you had two options (Also, the domed ones are cheaper)
 

Dan Freeman

Minister of Fire
Dec 3, 2021
769
NE PA
www.youtube.com
This brings up a question for me. Is the shape of a greenhouse important or make any difference? I can get the peaked roof style, or the domed style. I assume the only difference is aesthetic, or vertical space along the walls.

Does it negatively or positively affect sunlight within the greenhouse at all? Which one would you choose if you had two options (Also, the domed ones are cheaper)

In my experience I have never come across any information on the advantages of one shape over another when it comes to sunlight (PAR energy), although I have read of deep solar greenhouses where they talk about the pitch of your glazing for the most solar gain (both PAR and warmth). There is little leeway in roof shape when buying a pre-made greenhouse. With that being said, choice is usually a matter of taste, opinions/concerns about snow and wind loads, or an incidental factor when buying a specific greenhouse for specific reasons other than the shape.

For me here in PA, one of many reasons I purchased the Mt. Rainier in 2015 was because it has a steeply sloped roof and it sheds snow easily, a concern here in the Pocono Mountains (although not this year!). The biggest factor was that I was one of their online dealers at the time, and I got a deal I couldn't refuse!

I chose the Riga for numerous reasons (the price was not one! whew!). I do like the roof shape (onion) for snow shedding and wind loads, although wind load is secondary. We do get high winds at times, but my greenhouse is pretty well protected between 3 buildings and a hill.

So, long story, short, roof shape should not be the determining factor but one of many. You'll never buy the "perfect" greenhouse. There is a lot of give and take in the whole process.
 
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EatenByLimestone

Moderator
Staff member
Would the optimal angle for solar gain be the same as what you would want for solar panels? (Latitude?)

The steeper the walls, the easier they’ll shed snow.
 
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Dan Freeman

Minister of Fire
Dec 3, 2021
769
NE PA
www.youtube.com
Would the optimal angle for solar gain be the same as what you would want for solar panels? (Latitude?)

The steeper the walls, the easier they’ll shed snow.

Good point. I would imagine so. From my limited knowledge on the subject, I believe solar panels are set to get the best "average" over the entire year, no?
 

EatenByLimestone

Moderator
Staff member
I’d think so. I imagine, given the option, the panels would be more vertical when the sun doesn’t get as high.
 

clancey

Minister of Fire
Feb 26, 2021
2,437
Colorado
Kind of lost here are you too talking about movable solar panels or do they have that already?? Really stupid on this subject so be kind...lol clancey
 

Dan Freeman

Minister of Fire
Dec 3, 2021
769
NE PA
www.youtube.com
Much has happened since I wrote yesterday, and we have decided to move earlier, rather than later on the greenhouse, because of this...

I heard back from Site Prep LLC this morning. To install a level 14 x 20 pad with 4-6's anchored into the ground with rebar and 4" to 6" of tamped gravel in the middle on top of weed barrier is going to cost $2310. I don't think that is bad at all, and I don't have to buy and lug the 4 x 6's or the gravel or do any of the site/base prep. For me, that is worth it. It comes to $8.25 per square foot.

I remember leveling the 8x16 when we built it, and the 8x10 first chicken coup we built a few years earlier. I remember all that work just too vividly! You get tired real fast as you lift large 4 x 6's in and out of the foundation as you adjust, adjust, adjust the gravel to get it level. I found it back breaking 8 years ago; I can't imagine doing it now.
 
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clancey

Minister of Fire
Feb 26, 2021
2,437
Colorado
That sounds like a real decent price for a site prep and its the beginning on your planned greenhouse ----glad you are not doing that type of work by hand---and your ribs could not take it anyway.....You just "go for it"...clancey
 
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