My neighbor is getting rid of these, and I got 'em! Seems to me they would be perfect for a small greenhouse project…I could grow greens in-ground and have a shelf or two to start seedlings.
I’m beyond excited and doing some research but maybe someone here has personal experience with such a thing? I have a capable guy to do the work but I’d rather do the designing part of the job…
repurposing is a fine idea, though it can take effort on the what and how.
green house walls need to hold against the wind and the roof needs to hold against wind and rain/snow. supporting these large heavy pieces of glass will take framing that is up to the task.
you might also consider making cold frames (a short greenhouse for seedlings or short plants). though lighter glass might be preferred here it might be easier to use heavy glass.
you could use these as walls of the greenhouse with framing almost the same as would be needed to use these as doors in a house. then use smaller light weight plastic for the roof and gables.
I built a couple of hobbyist greenhouses and in both cases heating and cooling was more complicated than the structure itself. Assuming the glass doors are framed they should work fine as walls, described above. Heating and cooling will be highly dependent upon your local climate and in most cases I’m predicting more complicated than most people think.
I’m doing some research, because I agree…everyone I mention the project to says, oh sure! I can do that. Right now I’m searching for a local eco-type who can give me some guidance…I’ll be asking around at the food co-ops, etc.
I don’t really need a year-round greenhouse, which will help, I think. I just want someplace to start seeds and maybe lengthen the growing season for greens, etc. And to putter, of course. 
janeslogin, do you have any resources/books/websites you’d recommend?
No experience with greenhouses etc., although I always find garden structures interesting; However, bearing in mind the weight of the glass I’d suggest incorporating an existing brick or stone wall if possible.
I’ve no references but above reads as if you might want to do image searches on “cold frames”, “a-frames”, “hot-house”. Include the word greenhouse and plans in your searches.
Here is a set of general plans for using glass from sliding doors to build green houses and sunrooms. It is a guide for framing and sealing the glass, rather than specific plans for any one room design.
I guess I’m thinking more cold frame type greenhouse…I don’t want to have to heat anything. I’ll check out that link, too!
Right now all the doors plus two huge picture windows are sitting on my drive along with two twin bed frames. With the insane gardens growth beside the driveway plus the fact we haven’t been able to mow for two weeks, I feel like I live in a crazy-person house. All I need is a billboard proclaiming some government conspiracy handpainted and planted in my perennial garden.