Deep Winter Greenhouses — Passive Solar for Winter Food Production

Deep Winter Greenhouses — Passive Solar for Winter Food Production

Dan Handeen discusses a Deep Winter Greenhouse prototype being developed at the University of Minnesota. From the history to the “how-to”, Handeen’s informative presentation covers winter greenhouses in operation and in development around the midwest and around the world.


Minnesota Renewable Energy Society (MRES)


What do you think?


Written by Aleksandar

Video MakerContent AuthorYears Of Membership


  1. Great talk, but one major oversight.

    Straw bale adobe walls should be the near universal norm. At R-2 per inch of thickness, a two foot thick straw bale adobe wall can give R-48. And at $2-4 per bale, very high insulation standards can be met for very little expense. It is lower cost than polystyrene, rock wool/fibreglass, foam, and all other insulation types I know of – and it is a mold/pest/flood/fire/earthquake- and storm-resistant, non-toxic, non-polluting, low embodied energy, carbon sequestering, generally locally sourced, renewable building material set, that does not require petrochemicals or high energy use to manufacture.

    Why on earth is anyone talking about any kind of design other than non-toxic, passive solar, earth-integrated where possible, off-grid, solar and wind powered, straw bale adobe construction – with an attached solar greenhouse for heating the home or building, cleaning the air, oxygenating the air, further sequestering carbon, and generating on-site food production?

    It seems the leading edge of green home and building design is still 40 years behind, sorry to say.

  2. Horrible audio..loud first half of sentence, then mumbled the important stuff. Had to turn it off due to inability to hear the mumbles, especially while wiping face putting hand infront of mouth…lip reading out of the question.

  3. Also by not creating some-type of insulation under that thermal mass you are literally Heat-sink'ing all of your gain. The earth will take all the BTU's you could ever get into this system. If 50F is a great spec, why go through this hassle at all, and just sink your Green house into the 'pit' a little, forgo the stone, tubes and everything and maybe put in a couple aluminum heat-sinks into the ground to bring up a little extra surface area to the deeper earth for the cold nights.

    Even R3 under that slab would have a massive benefit and barely increase the cost. I am very curious to see your long term results. I feel that $500 in savings is going to harm your performance greatly.

  4. Use a intermittent Ozone generator up at the hot-air-intake, put it on a timmer and let the intake suck in a whiff of strong Ozone every so often, it will near-instantly get sucked into the T.Mass and oxidize its way through any mold/bacteria and likely be spent long before it would make it out of the exhaust. If you smelled any ozone in the structure you just dial back your generator.

  5. Curious if anyone has mentioned as an ALTERNATIVE source of heat for growing in winter … rocket mass heater? You will find that this uses about 1/4 of the wood a traditional wood burning stove would use. Typically, one can use the fallen branches in one's yard to heat an entire house of 1500 sq ft or so with JUST fallen branches from trees in a Canadian homestead. It works out to be about 25 lbs of wood per day when stove is needed. If on a somewhat lightly "wooded lot" one can achieve essentially free heat in this manner. I would encourage you to research this as you can put together a rocket mass heater for around $200 to $300 depending on size and scope. The best resource for this heating is found at:


Tomato Grafting: Greenhouse Design

Tomato Grafting: Greenhouse Design

A Self-Heating Greenhouse in the Pacific Northwest

A Self-Heating Greenhouse in the Pacific Northwest