Efficiently heating a swimming pool with a dual system
Heating a swimming pool efficiently has never been more important. Today energy costs are increasing at a rapid level and this means that owning and heating a swimming pool is becoming increasingly expensive. So what is the best, most efficient and cheapest way of keeping a swimming pool at a comfortable temperature.
Several factors come into play when determining the answer and these include the regional climate, the pool size and the available spend. How frequently the pool will be used and whether that use will be in or out of season should also be considered.
One way of maximising the heat that gets into the pool whilst minimising the energy that gets used to put it there is by having a dual heating approach. When this is the case two different systems are used to heat the water to two different temperature levels.
Free energy – a primary solar heating system
Without doubt the most cost effective way of heating a swimming pool is to use solar energy heating. Solar heating uses a water re-circulating matting that incorporates hundreds of tiny tubes into a mesh like material that uses the sun's rays to warm up the water. The water in the matting is continually circulated to and from the pool to the mat panels where it is reheated.
Not surprisingly this system requires bright weather with plenty of sun and the larger the matting area, the greater the potential to generate heat. Unfortunately the requirement for continuous sun combined with large solar gathering areas are the big downfalls of the solar system. Furthermore, it can only heat water up to a moderately warm temperature and this means that in many situations its potential is severely limited. At least if it is used as a sole heating system.
There is however another use for solar power in pool heating and that is as a partial heating system that uses a more powerful secondary heat source to create an extra boost of heat when the pool is in use.
A boiler – the secondary heater
When solar power is used to bring the temperature of pool water up to a certain level, a secondary heating system can then be used to give additional precise and powerful water heating control. This second heating unit could be a gas, oil or coal fired boiler, a condensing boiler, a heat exchanger, or a heat pump. Its job is to raise the water temperature by a few critical degrees and make the pool ideal for swimming.
Efficiency is increased and energy savings are made by using the free solar heat to give the water an initial temperature increase (from the ambient temperature). This is followed by using the more powerful energy burning system to top-up the heat to the required level. It is the initial raising of the water’s temperature that requires the greatest amount of energy and this energy is provided free by the sun. Hence the utilization of the boiler is significantly reduced, as are the energy bills.
More ways to conserve energy and fuel bills
Other ways of making already generated heat last longer (and conserving heat) include using a pool cover to prevent evaporative heat loss. Most pool-water heat is actually lost by evaporation. Stop the surface of the water from coming into contact with cold air and you prevent much of this heat loss.
Solar rings act in a similar way to pool covers and having a swimming pool enclosure that covers, or slides over, a pool will reduce heating charges significantly.