Solar pool heating systems are most often compared to natural gas pool heaters. This is natural as natural gas pool heaters have been around for a long time and all pool companies sell them. The fact is with a properly sized gas heater you can run your pool ALL year - including right through the Winter! Mind you it would cost an enormous amount of money to do that - which is why the vast majority of people don't.

Sorry to say that no solar pool heating system of any type or size can match the brute-force performance ability of a gas heater - fortunately they don't have to. Rather than having to try to heat a pool up in one day (or night), say Friday for the weekend, a solar system heats the pool up in two days, say Monday and Tuesday, and keeps it warm right through the week and into the weekend. And it does this for free - automatically. (You'll notice you have a pool ready for swimming much more often with a solar pool heater than when you heat with a gas heater.)

What about heat pumps? The companies all say they cost less to operate than gas heaters. Not true in Ontario. Perhaps in Quebec where electricity is really cheap and natural gas is scarce and expensive. In Ontario, a heat pump now costs twice as much in electricity as a gas heater does in gas to deliver the same amount of heat. Plus they cost much more to install, don't last as long, can be noisy and put a peak load on the electrical grid - just when the utilities don't want it! Bad news all around.

The graph below illustrates the relative costs of heating with the different types of pool heater.

Due to the short lifespan of heat pumps - the graph shows it being replaced twice in 15 years. The graph shows the gas heater being replaced once. The bump in the cost of the solar pool heating system operating costs in year 11 - is for the expense of removing and reinstalling the collectors when the roof is re-shingled.

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