Passive Solar Greenhouse Technology from China
Recently I heard about an interesting passive solar greenhouse design that was developed in China in the mid-1980’s. By the year 2000, these greenhouses covered about 260,000 hectares (650,000 acres) in northern China, and by 2004 they were supplying residents of northern China with 90% of their fresh produce in winter! The technology has since been brought to North America, but has yet to move beyond Manitoba in Canada where it was first introduced by a vegetable farmer named Wenkai Liu. The greenhouses consist of an insulated side wall, insulated end walls, and an insulation screen or blanket that can be rolled down over the southern surface at night. These houses maintain heat surprisingly well, and will remain above freezing even when temperatures drop drastically in the winter. The picture below shows a cross section sketch – dimensions are in meters:
You can learn more about these houses at:
https://energyfarms.wordpress.
https://www.engr.usask.ca/
https://www.hydro.mb.ca/your_
https://www.hydro.mb.ca/your_
very promissing for inner cities