> I've always wanted to see a practical combined heating and refrigeration system for a home that could tie in a fridge, HVAC, hot water heater, etc via CO2 ref

> I've always wanted to see a practical combined heating and refrigeration system for a home that could tie in a fridge, HVAC, hot water heater, etc via CO2 refrigerant. This has been done commercially for decades, but my guess is that the potential savings at home residential scale are not enough to offset the cost and additional complexity.