In cold climates, heating a house is more energy intensive than cooling it and electrical or appliance use. "Heat pumps" take the heat from the air or the ground and heat a house - this technology has been around for years and is already in hundreds of thousands of houses. Many people besides engineers and architects don't know about this heat pumps, but they are very effective. To break it down, a heat pump is essentially two coils wrapped around each other - one coil with cold outside air, the other with hot air. As the two wrap around each other they exchange heat, so the cold outside air is warmed before it enters the house. A compost sourced heat pump would do the same thing. It would take the heat from a compost pile (120-170 F) and use that to heat air or water for use inside. In this way, you could heat your home with compost. Really, heating your home with compost is not the big idea, the goal is to give people a reason to compost, to incentivize it. There are many reasons not to compost, but if you could heat your home with compost it might change your behavior. I imagine a world where instead of air conditioning units outside of every house there is a "compost unit" - to turn wasted food into heat. Think about how much energy is used to bring food scraps to a landfill, where it sits in plastic trash bags for thousands of years to come. Free the compost from its plastic prisons and let it warm you up, and you can change food waste into clean dirt instead of changing the climate.