Summer up here is too short to ripen the hot peppers and indeterminate tomatoes I like to eat so I grow them in my passive solar greenhouse. I put plastic milk jugs, full of water, by each plant. The water absorbs the suns heat during the day, at night the heat in the water radiates out keeping the plants warm.
I might get a few extra frost free weeks on either side of the growing season with these measures.
The students at the University Of Northern British Columbia, UNBC, here in Prince George, are building a Geodesic dome greenhouse to help extend the growing season even further, 2-3 months. They are planning to grow food to donate to the campus pub, the Thirsty Moose.
They bought a Geodesic dome kit and are going to erect the dome and plant it this spring.
These greenhouses make use of technology that is powered using energy from the sun. Things like: automatic window openers for venting, electricity to power a fan that blows air through pipes buried in the soil, keeping it warm, and the air temperature consistent.
Insulation on the north walls, called Reflectix, reflects light inside, keeping the dome warm in winter, and cool in summer.
A water tank absorbs excess heat, cooling the air during midday and warming it up when the temperature drops.
I’m impressed by the technology in this greenhouse and, excited to see it in action
Update: for more info on this project email-Cam