Quote:
Originally Posted by garyk  Every one knowes it is cheaper to heat water or air or whatever with a heat pump. With high effiency compressors and increased condenser area,,, very good. I see now two speed and even variable speed compressors now. For up to 20 SEER and up. COP of 9 and up.... WOW
The bottom line is cost ,,, cost ,,,, COST of installing and maintaining.
Go, GREEN |
A few corrections.
1.
COP
A COP at 50'C refrigerant saturation temperature, of 5 is thermodynamically possible - COP,hp ~ 9 is impossible at mid-range.
COP,hp ~ 8.62 at 30'C Tsat i.e. startup conditions.
These figures are using a scroll compressor, with high isentropic efficiency.
2.
Cost
The purchase cost is the main obstacle, after that, the electrical cost is negligible. Maintenance of a well-manufactured AWHP is almost negligible. The system should have less maintenance cost than a conventional a/c system.