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Solar Heating vs Conventional Heaters

 

Q:

Which pool heating system pollutes the least?

A:

Solar pool heating systems pollute the least of all pool heating systems. This is true for the lifetime cost which assess both the pollution created from using them and the pollution created in creating the heaters themselves. Natural gas and propane heaters would follow as the next least damaging to the environment, followed by oil and then heat pumps.

 

Q:

Are glazed or evacuated tube solar collectors better than the unglazed collectors for heating pools?

A:

For swimming pools that are only used during non-freezing weather in Ontario unglazed plastic collectors provide the best performance by far for the dollars spent. Both glazed (flatplate metal) collectors and evacuated tube collectors can do the job, BUT not with less surface area!! This makes the cost of these systems several times greater than unglazed plastic collectors. The reason is very simple. If the weather is so bad that glazed or evacuated tube collectors will perform better than an unglazed collector, the heat loss from the swimming pool will be so great that no solar system could keep the pool warm. (Neither could a heat pump. A gas heater could, but would cost a fortune to operate.)

IF the solar system is to be used for some other purpose as well as heating the outdoor pool - such as space heating during the winter - or if the solar system is to be used to heat an indoor pool all year round, then a glazed or evacuated tube collector system begins to make sense.

  

Q:

How does a solar pool heating system replace a gas heater if it can't heat as quickly?

A:

Most gas heaters are sized to (re)heat a pool in a "spot heating" mode rather than a "maintenance" mode. Spot heating refers to the practice of heating only for a short periods of time, i.e.: a weekend, or a special occasion - such as a pool party. Maintenance heating refers to the practice of leaving the heater on to maintain the desired temperature all of the time. The reason for using a "spot heating" mode is to save money. The reason for using the "maintenance" mode is to have the pool warm enough to swim in when you feel like swimming!

Solar pool heating systems are usually designed to operate as maintenance heaters. During periods of bad weather, both types of heaters aren't used. When the weather improves the solar pool heating system will bring the pool back up to swimming temperature (for free!) in about twice the time it takes the gas heater to reheat the pool (not for free!)(Also assuming that the gas heater is turned back on.)

 

Q:

Will heat pump pool heaters be banned in Ontario?

A:

It is possible that heat pump pool heating systems may be banned (or heavily taxed) in Ontario. The reasons are primarily environmental. There is no disguising that heat pumps are electric pool heaters, even if they are using electricity efficiently. These heaters draw power from Ontario Hydro's electrical grid during peak loads, when the whole electrical grid is straining to supply electricity during a heat wave. Provincial legislators may find it untenable that the grid could collapse and cause a blackout (such as occurred in August of 2003) because of people heating their pools with electricity!

In our opinion, heating your pool with a heat pump is financially and environmentally unwise.

 

Q:

Does a solar pool heating system work as well as a heat pump in Ontario?

A:

Properly sized and installed solar pool heating systems will heat a pool as well or better than most heat pump pool heaters. Heat pumps, like solar systems, do not work well when the weather is cool or cold. They do use a lot of electricity, require much more (expensive) maintenance, and do not last nearly as long as solar pool heating systems.

When comparing heat pumps to other types of pool heaters, the number to watch out for is the stated C.O.P. This number is often quoted as being 5 or 6. This number is misleading as it is derived from a "non-Ontario" climate. In the real (Ontario) world it struggles to reach 3 on an seasonal (average) basis. Also be aware of the tendency to use non-Ontario electrical rates when looking at the costs of operation.

Heat pumps are noisy. They make the same amount of noise as central air conditioners - only they run continuously for hours at a time. Solar systems make no noise.