Pool heating cost: what decides the price of heating a swimming pool

Size, temperature and season

A pool loses most of its heat from its surface, so surface area matters more than depth. The higher the target temperature, and the further into winter you want to swim, the larger the heater has to be. Extending the season into spring and autumn needs far less than keeping a pool warm through January.

The cover: the biggest saving

Evaporation is the largest single heat loss, and a cover stops most of it. A pool that is covered when not in use needs a smaller heater and costs much less to run; an uncovered pool in a windy coastal spot can lose heat faster than a modest heater can add it. Indoor pools lose less heat but need dehumidification for the room.

Heat pump, gas boiler or solar

A pool heat pump is the usual choice: it costs more to install than a gas heater but much less to run, and works well in Egypt’s mild winters. A gas boiler with a heat exchanger heats a pool quickly and suits pools used now and then, at a higher running cost. Solar collectors cost little to run and suit extending the season, often alongside a heat pump.

The pool’s existing pump, filter and plant room also matter: the heater is fitted into the filtration circuit, and limited space or a long run to the pool adds work.

Jacuzzis and spas

A jacuzzi holds far less water but is kept much hotter, so it needs a fast heater of its own or a priority circuit from the main heat source. Its water treatment and filters need particular care, since warm water and spray together are where Legionella thrives.