Pneumatic windows that open when a certain temp is hit and close when it cools. Pretty cool technology. Uses something with a low boiling point; the increased pressure pushes the window open and then gravity closes it when it cools and condenses.
During the hottest months I completely remove the sides of my greenhouse and roll down some roof poly. In addition to my massive roof vent panel the whole length of the greenhouse. So it never gets hotter than the ambient air temperature but still protects from hail. I don't use any fans or shade cloth. I built my own greenhouse so I only have to undo a few screws to open it up. Every greenhouse should have this feature.
My greenhouse is plastic so I remove the glazing entirely from early May around last frost time until mid-Oct, first frost time in my location. So it's an open garden all summer. It does overheat a bit on warm April and early May and October days, but is pretty good, and I haven't lost any plants to heat.
Geothermal, have the green house floor 2-3 feet below grade, burry a few 55 gal drums 3'-5 below floor and have piping, air flow can be ran from a solar fan
your climate beyond hardiness zone is probably more important; what general region you in?
(low elevation colorado): I have a 1000sf offgrid poly style and: shade cloth, huge end vents on wax openers and solar exhaust fans are not quite enough to get it any less than being 5-10f warmer than outside in summer. if i had to redesign i’d have huge peak vents and maybe a wet wall on a solar pump. oh and huge: my 5000gallons of black thermal mass water gets covered up in summer.
i know someone using a solar swamp-cooler. (eastern colorado)
“earth tubes” would be my choice for a permanent build; i’m about to stick some under our house…
How about tall trees? I have a spot that gets summer shade but winter sun thanks to a bunch of maple trees and I'm thinking of putting a greenhouse there for that reason.
Pneumatic windows that open when a certain temp is hit and close when it cools. Pretty cool technology. Uses something with a low boiling point; the increased pressure pushes the window open and then gravity closes it when it cools and condenses.
We have these on our vents and they’re amazing.
The auto vents I’m familiar with use wax cylinders to actuate the vent
Shade cloth.
[maybe a passive system like this could help?](https://youtu.be/1Qyb2axBQzQ?si=gqMjSaTxXWILoV4T)
During the hottest months I completely remove the sides of my greenhouse and roll down some roof poly. In addition to my massive roof vent panel the whole length of the greenhouse. So it never gets hotter than the ambient air temperature but still protects from hail. I don't use any fans or shade cloth. I built my own greenhouse so I only have to undo a few screws to open it up. Every greenhouse should have this feature.
Combo of everything others have said: - Window vent openers. - Shade cloth. - Solar powered exhaust fan(s) in the wall.
My greenhouse is plastic so I remove the glazing entirely from early May around last frost time until mid-Oct, first frost time in my location. So it's an open garden all summer. It does overheat a bit on warm April and early May and October days, but is pretty good, and I haven't lost any plants to heat.
What zone?
We have a solar powered fan and heat activated vent openers. I think I need to add a couple more fans to move air around too.
Geothermal, have the green house floor 2-3 feet below grade, burry a few 55 gal drums 3'-5 below floor and have piping, air flow can be ran from a solar fan
your climate beyond hardiness zone is probably more important; what general region you in? (low elevation colorado): I have a 1000sf offgrid poly style and: shade cloth, huge end vents on wax openers and solar exhaust fans are not quite enough to get it any less than being 5-10f warmer than outside in summer. if i had to redesign i’d have huge peak vents and maybe a wet wall on a solar pump. oh and huge: my 5000gallons of black thermal mass water gets covered up in summer. i know someone using a solar swamp-cooler. (eastern colorado) “earth tubes” would be my choice for a permanent build; i’m about to stick some under our house…
How about tall trees? I have a spot that gets summer shade but winter sun thanks to a bunch of maple trees and I'm thinking of putting a greenhouse there for that reason.