Solar energy proves more effective than a pool cover
Using solar thermal energy to heat a luxury Infinity pool at a large house in Essex cost only half as much as reducing heat loss using a pool cover and did not limit the scope of having an interesting pool shape. MHS boilers supplied 10 m2 of evacuated tube solar collectors and a Euron wall-mounted 30 kW condensing boiler, along with controls package, for the project.
The solar thermal system delivers about 12 kW of heat to minimise the use of the boiler to heat the pool to 29°C.
Grant Davis of Clearwater Marine Technology, designed the system. He explains, ‘A pool cover cannot save energy whilst the pool is in use. By using solar thermal, not only is the installation and capital costs less than a pool cover, it is using free energy from the Sun and has a much longer lifespan.’
The 12.5 by 7.5 m 86 000 l pool has an average overnight temperature loss of 2 K. The boiler runs for a couple of hours early in the morning to bring the pool up to 29°C, after which the solar system starts to contribute. On a sunny day, the water can reach 33°C and 29°C on an overcast day.
The solar system heats the pool water via a heat exchange that is in series with an upstream of the heat exchanger served by the boiler. In this way, the boiler is required to do little during the day when there is reasonable solar energy available.