The fruit wall... forerunner of the European greenhouse

[margali]

eventually we have to figure out how to do a closed system anyways in like an asteroid or such... can use some materials to reflect light from outside inside, but there would need to be some sort of very good seal/vacuum to provide insulation.

It's been envisioned in a couple of ways- Enveloping a sun is called a dyson's sphere and mega tech.
The version I find the neatest and almost achievable with today's tech! is a troy. This is from John Ringo's Troy Rising series. Use large space mirror to melt metallic asteroid to impurities are removed. Drill whole to center and stuff with ice. Cap and boil yourself up a metal balloon. Light inside with light direct by space mirror.

 

[digitS']

Closer to home, each year a temporary plastic film hoop house goes up in my backyard. (I've had it up in early March before but feeling just fine that it isn't trying to stand up out there this morning because the minimum of 3" of snow is falling and it has collapsed in those conditions .) The 9' by 20' structure is held up by 2 by 4 door and window frames at N & S ends and pvc hoops between.

The center path between 2 beds is about 18" deep because the hoops reach a height of only 5'. I step 2 steps down into a vestibule and walk in.

Immediately north of the hoop house is the sunshed greenhouse of the same size. It protects the hoop house as does the board fence, garages, and carport to the west and south. It's a sheltered little garden and that is what it changes back to in July after sheltering those 2 beds under plastic for a couple of months.

The sunshed greenhouse stands year-round with its wood frame north wall and roof.

Yes, I have wondered about insulated, conventional buildings using electricity for the entirety of light required by plants. I worked in commercial glass greenhouses and they lose a tremendous amount of the heat pumped into them.

Still, electric lights would have to run regardless of daily sunlight and outdoor temperatures. Some lights generate a good deal of heat, useful in cold weather but requiring ventilation in warm. That is, unless the building's interior temperature would be static by being entirely underground.

Steve, fresh-air Earthling

 

[TwinCitiesPanda]

Why haven’t greenhouses caught up to advancements in household glass yet? Probably cost. Double or triple pane windows with vacuum or argon between them can provide considerable insulation. In a greenhouse I imagine you could increase the pane spacing considerably since their purpose is to capture light and heat, not to see out of like household windows. Also a greenhouse with an shiny coated insulated panel on the walls and only the top made of glass would reduce loss out the walls and help make better use of the light entering through the roof.


I wonder if a traditional greenhouse is even worth it anymore from an energy perspective. Why not a well-insulated shed with no windows and high performance solar panels on top to power LED lights within? You’d probably lose less energy that way than in a greenhouse.

 

[Rhodie Ranch]

fascinating article. Thanks! I love learning something new all the time.

 

[digitS']

My commercial greenhouse experience is from 30+ years ago. Still, I'm not sure how much advancement they have made, @TwinCitiesPanda .

The noise from the hobby greenhouse manufacturers should have been debunked during that time but the "back to the Earth" movement was fairly strong. We were told by those who had done the research that about 10% of sunlight was lost even by the best of glazing materials. Double that plastic or glass and it was 20%. Where I live is not quite as dark as Seattle or points north but it's still the Pacific Northwest. Winter skies are overcast a good deal and the angle of the sunlight is very low at 48° North. The winter sun isn't up long. It hardly makes sense to try to grow something in a greenhouse during winter months while losing so much sunlight. Shucks.

If I can get things transplanted in there by October that can take a frost, and still cover them when the outdoors drops below about 15°f, I can harvest those hardy greens in December - even without turning on the heat. Tiny plants started from seed in October won't be large enough to harvest in January. They will be available for February and March ... sooo, how about 2019? Missed the boat! I had planned to put new UV-resistant plastic on by this time so the dang thing would have been exposed to some real cold when I took the old film off. Ooops! Didn't plan on all this snow. It slides down the south wall and piles up. I cannot walk on the west side except to get to the door. So much snow has slid off the carport that I'm lucky that it didn't knock the southwest corner of the greenhouse down! Of course, it is all a frozen glacier right now. Hobby greenhouse? Weellll, it looks like this hobbiest will be replacing the east wall which is the worst plastic ... as luck will have it . We will see when and if I can pull the other walls off as I'm already carrying seedlings out there during the daytime and should soon be needing to leave them overnight. Furnace better work!

Steve
envying those in more southern latitudes

 

[flowerbug]

i've always imagined a house on hydraulic lifts that you could raise or lower depending upon the weather/wind/sun/storms/etc. have the roof well insulated and it would seal up as it came down against the ground. if you wanted to see what was up outside you could have cameras. nowadays with the very low energy LED type monitors it really isn't a bad idea to have your natural view coming in from a camera and have a nice big screen on the wall instead of a window anyways. this is because no matter how well you seal up and insulate layers of glass it still loses heat from the frame. you need a pretty well designed unit to keep that loss to a minimum.

underground you get the advantage of the insulation and steady temperatures. if you heat pump using solar energy and wind energy you can really be quite comfy. the problem is that underground you can have water leaks and air quality stuff happening you want to watch out for. for certain, here, can't do things underground, the water table is way too high...

the greenhouse for the northern climate is nice to use to extend the season but i would never try to keep it warm all winter unless i had very cheap free heat/energy. that's why underground makes more sense anyways. avoid the heat-sucking through windows and walls...

 

[digitS']

 

[margali]

My idea house would fit right into a Hobbit village. Bedrooms is the back with no windows. Skylight and or windows in office and living room.