Electric
resistance heating is generally considered to be 100% efficient.
That's because almost all of the electricity put into a resistance heater
comes out as heat.
The misconception that sometimes traps and confuses people is thinking that this is the entire story, and forgetting that making the electricity and getting it to the heater was not 100% efficient. If you take into account the efficiency losses of the power plant where the electricity was produced, and the losses that take place as it travels through the distribution system, resistance heat is far less efficient.
Another misconception is that even though its "site efficiency" is
100%, it does not mean it is least expensive to operate. Electricity
is such a highly refined form of energy, it is usually more expensive per Btu
than many other forms of energy, like oil, gas or coal. Electricity is made
at a distant power plant where the owner must deal with purchasing fuel and
all the environmental concerns associated with burning it, then it must be brought
to homes and businesses where is can be 100% efficient. Therefore, electricity
is usually more expensive on a "Btu to Btu" basis than some other
fuels you have to burn on site like gas or wood, but you are paying for convenience
and simplicity when using electricity.
