> That despite much of our energy being generated with natural gas, probably in a much more efficient way than my furnace does. Assuming modern equipment and C

> That despite much of our energy being generated with natural gas, probably in a much more efficient way than my furnace does. Assuming modern equipment and California weather, your gas furnace will be more efficient at gas to heat than a gas plant supplying electric resistive heat, but less efficient than a gas plant powering a heat pump.