nortcan wrote:can produce more energy than it consume to produce heat when the outside temp. is about 5*C or above.?
The fuel source for the heat is the air, it's not the electric. When you compress air and anything else that can be compressed you're also compressing the heat energy in it. If you want a simple analogy it's just like mining, instead of using a machine to mine BTU's in coal you're using a machine to mine BTU's from the air.
A heat pumps efficiency versus standard electric depends on the outside air temperature but it can be 3X as much, that's why they are given efficiency ratings higher than 100%.