I live between 44° and 45° N in New England and I want to design a greenhouse that can keep itself above freezing year round without using electricity from the

I live between 44° and 45° N in New England and I want to design a greenhouse that can keep itself above freezing year round without using electricity from the house. So if I can do some cool solar pv hydronic heat tank thing, that's ok, or use giant coils of air tubes deep within the earth to steal ambient heat, or whatever tricks look good... I want to give it a shot!