Anyone grow food in one? I like the idea of growing avocados and citrus where the winter low temps would ordinarily kill them if they were outdoors.
Sounds like heating costs ( fuel or electric) alone would likely be higher than just buying fruit at the store. Been daydreaming about geothermal / ground-source heating, and collecting solar energy in thermal storage.
You can potentially grow all year round and eliminate heating cost by doing an semi-underground greenhouse. There'e plenty of tutorials online, and it doesn't have to be extremely deep or large for the matter. When deciding to get into growing or a greenhouse, your best way to start and pursue that idea is to just grow anything.. literally. Grab cups, pots, or whatever.. grow whatever seeds you have. It's a hobby that takes relatively little time each day, but does take a semi-amount of skill. Using a special calendar to keep track of when you've watered, or added any sort of fertilizer will keep you from over watering or burning up the plant with too much booster.