In Germany, the weather is such a thing: In some years we have a lot of spring and autumn weather, but little real summer heat. For many garden owners, these few days are therefore worthwhile expensive pools not at all. But its water can even be heated with the autumn sun and already cooled air.
“Basically, every pool can be heated,” says Ute Wanschura, Managing Director of the Federal Association of Swimming Pools and Wellness in Cologne. The heater can also be retrofitted.
“You just have to consider whether investing in a heating system is worthwhile very cheap above ground pools worth it.” But even there, the water can be heated with an electric heater.
Larger, permanently installed pools can be heated in a more environmentally friendly and sustainable way with a heat pump. It extracts heat from the air or the ground, pumps it with electricity to a higher temperature level and transfers it to the pool water. According to Ute Wanschura, this process is possible for pools from an outside temperature of around twelve degrees.
The amount of energy that the heat pump consumes is less than the heat that it generates: Modern models can generate up to five kilowatt hours of heat with one kilowatt hour of electricity. But of course that also depends on the outside temperature.
“The lower the temperature difference between the outside air and the desired pool temperature, the less energy the heat pump has to produce itself – the more efficiently it works,” explains Wanschura.
Heat the swimming pool with the sun’s rays
This is also a comparatively energy-efficient alternative heating the pool with solar energy. “The simplest solution are plastic absorbers, which are available in the form of mats, panels or hoses,” explains Carsten Körnig, General Manager of the German Solar Industry Association in Berlin. They are mounted directly in the garden, on the house roof or on the garage roof.
The pool water flows directly through the absorbers and heats up in the process – like in a garden hose lying in the sun, describes Ute Wanschura. In this way, temperatures can be achieved that are four to ten Kelvin higher than that of an unheated pool – which corresponds to four to ten degrees Celsius.
“The pool should be as close as possible to the absorber in order to keep heat losses in the pipework to a minimum,” advises the pool expert. And Carsten Körnig advises that the area of a plastic absorber should ideally be 0.7 to 1.2 square meters of absorber area per square meter of pool surface.
find the right pool heater now on WELT comparison
Use the house heating for the swimming pool
The second solution with solar energy are collectors, as they are also known for heating the building from the roof, but in this case they are installed near the pool. Unlike the solar absorbers, swimming pool water does not flow through them, but instead a frost-proof heat transfer fluid that is also heated by the sun. A heat exchanger ensures that the heat generated is transferred to the pool water.
The alternative to this is to directly use the solar thermal system for the house for the pool as well – namely the excess. This is pointed out by the VdZ Central Association of Building Technology. The energy obtained via solar collectors is temporarily stored in a heat storage tank and made available for heating and hot water as required.
After all, in the warm months, the yield of solar energy is particularly high, but the heat requirement in the house is rather low. This surplus can then be used for the pool, for example.
photovoltaic solar cells on the roof.”/> According to VdZ, a solar thermal system is significantly more complex and therefore more expensive than the purchase of solar absorbers – after all, this is also a heating system for the house.
But if you plan to do this anyway, you can save energy costs in the long term. In combination with a modern oil or gas condensing boiler, for example, energy savings of up to 40 percent per year are possible.
A roof keeps heat in the water
Pool expert Ute Wanschura also recommends integrating the pool heating into the house heating system. “This is usually the more efficient variant, since all the components are networked with each other and work in a coordinated manner.” The pool heating can also be controlled manually.
To keep the water in the pool warm for as long as possible, a roof is required for the pool. According to Wanschura, a roof can reduce the energy required to heat the pool by up to 80 percent.
Roller shutter covers are pushed over the surface of the water like roller shutters on a window – this way the water in the pool retains its heat better
Source: dpa-tmn/pool concept
This cover can be very simple: Even a simple bubble wrap has an effect. But there are also options with integrated solar profiles that practically have a double effect. On the one hand, they keep the heat in the pool, on the other hand, the solar profiles absorb the sun’s heat and pass it on to the pool.
“However, roller shutter covers that run over water like a window shutter and can also be operated by remote control are nicer,” says industry expert Ute Wanschura. “Roller decks, which are rolled over the pool and can then be walked on like a terrace with wooden panels, are also becoming more and more popular.” That way you can still enjoy the pool even if the heating is no longer able to warm the water.
Pool construction and conditions
Swimming pools with a volume of up to 100 cubic meters need in most cases no building permit, if they are, for example, an ancillary system to a residential building. However, there may be exceptions to the details and building regulations.
And: Due to the recurring dry seasons in some parts of the country, some cities and municipalities now temporarily prohibit the filling of pools in private gardens in summer – or at least call for people to save water.