[eldred]

We also wanted to be able to swim year round and I do like the water above 80 degrees. In looking into it, new model heat pumps are good down to 35 degrees and are much cheaper to run than gas. At very low temps they still work, but not as efficiently. We were able to buy a 96,000 BTU heat pump on line for $3300 and T and D installed it for $150. The company did the calculations for our pool and a heat pump was significantly cheaper to run. I have attached the costs they calculated. It is true it can't heat the pool as quickly as gas would, but it easily kept it at 85 degrees this last winter with a blanket The calculated cost difference was $1086 for heat pump versus $6255 per year for gas, which more than repays the cost of the heat pump. If you really want to save money you should use a pool cover in colder weather. It depends how much you want to spend. Using a floating pool cover in cold weather with the heat pump lowers my yearly heating costs to just $434 which works me. You would definitely need a pool cover for just solar in cool weather. You can also get a liquid blanket to save heating but I don't want to swim in chemicals. It is great to swim year round.