posted 9 years ago
The walipini is not a magic bullet and there has been some difficulty in adapting a greenhouse designed for tropical latitudes. Pit greenhouses (also search for: underground, semi-underground, earth-sheltered, sunken) are not a new concept and there are many options, including above-ground greenhouses that use earth tubes to moderate temperature.
You might want to track down a pdf copy of Mike Oehler's, The Earth Sheltered Solar Greenhouse Book. I would also recommend Solar Greenhouses: Underground, by Daniel Geery, 1982, Tab Books Inc. There are no digital copies available that I am aware of, but you can get a used copy at a reasonable price on Amazon (shipping to Hungary might be discouraging, but you would know better).
There is a lot on youtube, as well as a simple internet search using the terms listed above. My primary recommendation is to not get stuck on a name or a single design. Do as much research as you can and then do some designing to adapt to your particular site and needs. You probably won't get it perfect, but you will have something.
The Geery book goes into great detail about optimum glazed area and angles, as well as reflective materials.