This Maine dwelling can keep 70 levels with no furnace, even when it’s freezing exterior

This story is a part of Maine Public’s collection “Local weather Pushed: A deep dive into Maine’s response, one county at a time.”

What if you happen to may design a home that on a chilly day in January would keep at 70 levels inside — with out operating the furnace? And even having a furnace?

It’s already being executed.