Solar thermal systems for pool heating are so common and mainstream that most manufacturers provide very detailed installation instructions. It is important to follow these instructions as they outline the most efficient way to install the equipment.
Although you may be (or think you are) an accomplished DIY expert, don't ignore the documentation – it often includes many useful hints and tips gathered from years of installation experience!
Solar swimming pool systems are among the simplest available. Maintenance is equally simple and is carried out at the start of the warm season, before the system is used.
Much like seasonal swimming pools, spas and hot tubs can profit enormously from solar heating systems. This is especially true if you're installing a solar thermal system for your domestic hot water supply or space heating because the tub or spa can act as a shunt load, using excess output from the household system.
Swimming pool heating is the single most popular use of solar thermal systems: more collectors are sold for this purpose in the USA than for any other installation. In fact, solar pool heating is so popular that, on average, seven pool collectors are sold for every flat plate or evacuated tube model.
Why are they so popular? Because they're cheap, simple and save lots of money – a solar thermal system for a seasonal pool can pay for itself in as little as two or three years!
Indoor swimming pools have exactly the same heat load throughout the year. A solar thermal setup can provide 50% of the load in winter and 100% in summer – the amount varies because there's less solar radiation in winter to generate heat. In general, an indoor pool solar thermal installation is sized to generate the right amount of heat on the best possible day: this ensures that the system never overheats.
When you first set foot in the renewable energy arena, it can look daunting: different technologies, different approaches, net-zero, net-positive, PV arrays, solar thermal, geothermal, wind power... it's a big subject and can be confusing. So where should you start?
There are some things you can do to save energy and money before you install even the simplest renewable energy system. The three simple steps are to reduce losses, increase efficiency and reduce consumption.
The single biggest use of solar thermal systems worldwide is to heat swimming pools. As a result, special technologies have appeared that facilitate this use, the best of which is a web-and-tube setup. The requirements for seasonal pool heating are much simpler than those for a whole-home, all-season solar thermal system: the water only needs to be heated to a little above ambient temperature, the collectors don't need to be climate-proof (as they're only laid out in hot months, when needed) and they don't need any glazing.
If you're installing a solar thermal system in a location that gets a lot of direct sunlight and you're doing it on an industrial scale, you might want to consider concentrating collectors. Unlike normal collectors, these won't work with indirect sunlight, but they're a lot more efficient than any of the other types if your location, scale and budget allow their use. Concentrating collectors use the simple scientific principles of focusing light to concentrate the sun's energy onto a single point.
