I was thinking about giving my friends and their kids (more for their kids) a little treat by heating our pool one weekend day this month. While the cost is a factor, I am curious if it would even be enjoyable? Let's say we heat the pool to 85* and the outside temp is 50*. Would that even be enjoyable if there was a slight breeze? I am curious what others have done and experienced. What is a good temp to raise to so it's enjoyable?
I live in Houston TX so who knows what the temperature would be like on any given day. One day it can be 80* and the next 40*, esp as we get close to Jan.
As far as cost goes, it seems pretty reasonable to heat our pool for a one-time use. We have a 400,000 btu heater that runs on natural gas (not sure it matters too much except for the efficiency). Our pool is 18k gallons. Let's assume I raise the temp by 20*. At 8.3 lb/gal, I get ~3mm btu to raise the pool by the desired amount (18,000 gal * 20 degrees * 8.3 lb/gal). Assume nat gas costs of $0.70/therm (or /ccf) right now in Houston. 1 ccf = 102,000 btu. 3,000,000 btu * $0.70 per 102,000 btu = $20.50. Obviously the cost will be higher than that since the heater is not 100% efficient, so we can assume $25-30 based on my math. Does this seem reasonable?