Carrier is about to release it's new "Green Speed" Heat Pump. The efficiency ratings are off the charts!

With a HSPF (Heating Seasonal Performance Factor) up to 13, this is nearly twice the efficiency of heat pumps made just a few years ago. This is accomplished be using a compressor with Inverter Drive technology. Think of it as having the ability to shift through a near infinite set of gears automatically. Most Heat Pumps only have one, or possibly two speeds. If you were to drive your car in second gear on the hiway.....sure you would eventually get where you are going, but the performance would be pathetic. Without overdrive, you would only waste energy. With the new Green Speed Heat Pump, the sophisticated controls react to varying demand & load conditions. This allows the system to operate at peak performance and the highest efficiency.Carrier GreenSpeed Heat Pump Brochure