Why are heat pumps more efficient than baseboard heating?
If electric baseboard heating is 100% efficient in terms of turning the electricity they use into heat, then how can they possibly get a bad rap for its inefficiency? Well, because, in fact, heat pumps are more than 100% efficient. Huh? Yes, baseboard heaters have a 1:1 efficiency of watts produced to watts used, or an equivalent efficiency of 3.41 of BTUs produced to watts used, which is known as its HSPF (Heating Seasonal Performance Factor). But run-of-the-mill heat pumps have an HSPF of twice that, and to get an EnergyStar rating as efficient, heat pumps need to have an HSPF value greater than 8.1 for ducted heat pumps and 8.5 for non-ducted to be deemed efficient for cold climates.
How can heat pumps be well over twice as efficient as baseboard heating when baseboard heaters convert every bit of the electricity they use to heat? Well, because heat pumps carry heat. Think of a tanker truck carrying gasoline to neighborhood gas station. From the fuel depot, say, 50 miles away, it maybe only got 5 miles/gallon. Horrendous milage...10 gallons to go 50 miles. But, it's carrying 10,0000 gallons which can be delivered. Heat pumps work sorta the same way. They use a bit of fuel (maybe 1,000 watts) to carry maybe 8,000 or 9,000 watts of free heat from the outside to the inside to heat a home. So, 8,000 watts/1,000 watts would give such a heat pump an HSPF of 8. But wait, how can a heat pump's refrigerant carry heat from the outside if it's 15 degrees outside? Well, it may not feel very warm outside, but there's enough heat in the air there to be absorbed when the super-cold outdoor coil comes into contact with it, and that heat can then be transferred to the inside where it becomes even warmer after the refrigerant carrying it has been compressed. It's magic, but that's the refrigeration cycle for you.
Baseboard can be efficient, even more efficient than a traditional heat pump, if you're spending all of your time in one room, since a normal furnace or normal heat pump pushes air through the ducts of the whole house, and that's wasteful if the occupants are working in one office of the home or sleeping in only one bedroom. But, these days, an option to doing whole-house ducted heat pump heating is mini split or variable-refrigerant (VRF) units that can have a smaller unit in each room. That way, the heat is targeted to where it's being used, and it's being generated in a way that's 2 or 3 or even more times more efficient than running baseboard heating. Because of this, VRF heat pumps are the way of the future for helping people save money while they save the environment.