With the ever increasing cost of energy, heating the swimming pool
is starting to become a luxury which needs to be bought under control.
If the pool is heated by oil or gas(calor or natural) then a solar
panel or heat pump solution is a very viable answer to bringing that
expense under control.
A solar panel solution using heat tubes or flatpanels works on the
basis of trapping the heat of the sun inside an evacuated tube, then
conducting and convecting it up a copper tube to a manifold. The manifold
has an antifreeze based solution being pumped through it around the
system. The fluid cools the copper top of the heat pipe, so the bank
of heat pipes as a whole collects the suns energy and puts it into
the fluid. The hot fluid is then taken through a very efficient heat
exchanger, which has the pool water running through the alternate
side. The heat transfers to the cooler pool water and hence heats
The size of the system depends on a number of factors,
1.The size of the pool and hence the volume of water
2.The losses from the pool e.g. cover quality, inground/aboveground
3.Are the collectors facing due south and is it a very cloudy area
4.Is the system being used to heat the house DHW as well or a pool
5.How much will it be used, many users increase the heat loss.
These factors will all be taken into account, and a suitable size
of system suggested, so that although a boiler may well be needed
to give the pool a bump up at the start of the swimming season, the
solar system will hold the temperature after that.
We are seeing Solar payback times of 3-4 years for oil/calor heating
and approximately 8-10 years against a natural gas boiler. The ongoing
running costs of a typical solar solutions are negligible as the system
needs a 40watt pump to take the hot fluid from the panels to the heat
exchanger. These systems are ideal for external pools which are normally
only used in summer months.
An Indoor pool which is used all year will need a different system
to heat it during the winter. Heat pumps can be very useful for heating
indoor pools as the power from the sun (solar insolation) is 10 times
less in the winter than the summer. They are relatively cheap, but
cost a great deal more to run. The ideal solution is to use the solar
radiation in the summer with a solar panel solution and a heat pump
to carry the pool through the winter. With this model there is no
need to have a boiler.
Heat pumps will pay back their capital cost in 2 to 3 years, but will
only reduce the heating bill to 25% if you are running at a Coefficient
of Performance(COP) of 4. This means for every 1kW of electrical energy
you put into the system you get 4kW of heat equivalent.
With gas having to be imported from Russia and gas and oil from the
Middle East we are very exposed to massive price fluctuations, so
it makes sense to limit the reliance on those types of energy supply.