Heat pumps are very popular in New Zealand…though the term seems to mean different things in different countries. In North America, I was under the impression that heat pumps exploited the difference in temperatures between the earth underground and the air above ground. In New Zealand, they’re essentially “reverse air conditioners” which syphon off the warmth in exterior air and pump it into the house interior. As such, they are more efficient for home heating than a simple wire coil plugged into the wall (i.e., the traditional electric heater).
We don’t have a heat pump yet, but we’re also researching them at the moment because houses our so damn cold here in New Zealand (no insulation!). Toshiba keeps coming up as a brand that is supposed to be very reliable. I’m interested in anything people know about heat pumps too.