After your heating and cooling system, the next biggest energy hog in most homes is your swimming pool. I won’t feel bad if you skip this podcast if you don’t have a swimming pool — unless you’re an energy geek like me. My recent experiences addressing the energy problems in my old house really focused my attention on my swimming pool; in comparison, fixing my HVAC system was relatively easy (that's the subject of another podcast).
Here is a summary of my annual pool expenses: $1,300 for pool pump electricity ($0.45/kwh), $1,800 for pool maintenance, $500 for evaporative water loss (1.5 cents/gallon), $100 every time I want to heat up the pool in the spring/fall for the weekend ($1.75/therm), and $10 every time I want to heat up the spa. I’m too busy on weekends to do the pool maintenance myself, and the pool’s oval shape is not conducive to a pool cover. So I focused on reducing my pool's electricity and gas consumption.
It was surprisingly easy to cut my $1,300 electricity cost down to about $130 per year. First I installed a variable speed pump (about $1600) — if you have a pool, do this now. Second, since this pump is so quiet I run the pump at night during off-peak rates -- currently $0.13/kwh. Third, with solar power on my roof my costs are down to about $65 per year ($0.07/kwh for solar electricity amortized over 25 years).
Keeping the pool at a comfortable temperature is usually more problematic…except for our family since my wife and I don’t swim, and the kids generally don’t care how cold the water is. But if you want to keep your pool comfortably warm in the spring and fall, the best option is a solar pool heating system that uses black plastic collectors mounted on your roof through which pool water is pumped. Note that if you have this type of system you will need to run your pool pumps during the middle of the day — which may be during peak electric rate times. Another option is a pool heat pump. Air to water heat pumps are good in warm and humid climates (not always best in hot and dry climates). If you are more concerned about heating a spa, a water to water heat pump (cooling the pool and heating the spa) might make sense.
For more about reducing your pool’s total operating costs so it's no longer an energy hog, Listen up to this week’s Energy Show.