Speaking of solar greenhouses (at the price of possibly digressing)...
We just put together a tiny solar greenhouse kit - about 3' high, 3' wide, 1' deep, with three rows of trays for growing plants, made of a thermoplastic.
We set it up on the south wall but hadn't filled it with dirt, water, and plants yet.
Next day the trays had melted enough that the top row had collapsed onto the second.
Solar power and the greenhouse effect are not trivial!