Solar pool heaters are the most common use of solar thermal technology in North America. This is because they are extremely cost effective: a solar pool heater will typically pay for itself in 2 to 3 years (Can. Solar Industries). Even without considering the savings in greenhouse gas emissions, solar pool heaters make a lot of sense. The total price of solar heating a pool is usually $3,000-$4,000 US including installation, but can range from $2,500 to $7,000 US (Costhelper.com).
Solar hot water panels used in pools are flat plate collectors. They are usually made of rubber or black plastic and are a very simple use of solar thermal technology compared to solar water heating systems for drinking water.
The solar hot water panels are usually about 50% of the pool’s service area. If a pool is indoors or is not in direct sunlight, a larger area of solar heating panels must be used to reach the same temperature. A pool cover should be used at night to reduce heat loss. If you don’t use a pool cover, you’ll need to install twice the area of solar hot water panel.
While solar pool heaters make excellent sense for swimming pools, they don’t work as well for hot tubs. The water temperature can be raised high enough using metal collectors used for heating domestic water, but if the jets in the hot tub are used, the water will swiftly cool down again.