If your blue swimming pool literally turns green, that's an alarming indication of algae invasion. But making it metaphorically a little greener – that is, minimizing its electricity, water and chemical consumption – is a boon for both the environment and your wallet. An array of newer technologies and time-honored tricks can transform your pool into more frugal fun this summer.
When we moved into our Canyon Country home four years ago, there were already rooftop solar collectors to heat its 18,000-gallon pool. These black panels, which circulate water through tiny "veins" to be heated by the sun, are so effective that we often find ourselves turning the heater down in the middle of summer. The system also extends our annual pool season, and costs absolutely nothing to operate (by contrast, running an electric heat pump or gas pool heater costs $100 to $300 per month). The pool pump is the other big power guzzler with pools, typically adding $60 to $90 per month to a home's electric bill. The electric motor circulates the water through the filter and needs to run for many hours daily.
The most reliable way to keep these costs down is to install a modern variable-speed pump. Compared to traditional single- or dual-speed units, a variable-speed pump consumes less power because it can be programmed to run at minimal power for much of its daily cycle (for example, while just filtering water). Variable-speed pumps are priced higher, but making the switch could save you over 80% in energy costs, likely paying for itself within a couple of years. To eliminate the costs of running a pump altogether, solar pumps, which come with a dedicated array of small solar panels, are now available. However, since pumps need to run almost constantly, these are viable only in certain consistently sunny situations.
Programming the pool pump (i.e. when it will run and how fast) is also crucial to affordably maintaining a pristine pool. Trial and error is key, and will vary depending upon the time of year, location of the pool, and the amount of use it gets. The pump should definitely be circulating water during those hours when sun is hitting the surface, as algae thrive in still, sunlit water. Also, it takes time to thoroughly skim and vacuum a pool (both functions normally powered by the pump) each day. An experienced pool service can help ascertain the optimal settings for your circumstances.
Consider covering your pool when it's not being used. The eco advantages of adding a pool cover are threefold. Evaporation is easily the biggest source of energy loss from a heated pool, as the already warmed water lost is replaced by cold. While the rate of evaporation from a given pool depends on its surface area, air temperature, and wind speeds, Energy.gov estimates possible savings of 50% to 70% on heating costs simply from installing a pool cover. It follows that a cover also reduces the amount of water needed to keep a pool properly topped up (in windy locations, adding a fence or trees as a windbreak can also decrease evaporation). Thirdly, keeping the sun off the water as much as possible will limit the risk of sunlight-loving algae, and saving you money on the chemicals required to keep the annoying organisms at bay. Energy-saving LEDs are now also an option for pool lights. Solar lights can also be used to illuminate the area around the pool, or even float in the water itself. While shopping for electrical pool equipment, including pumps and lights, seek out products with Energy Star certification, which indicates energy-efficient operation.
A pool can also lose water through leaks in its plumbing, fittings or shell. However small, these can become costly over time (not to mention endangering the pool's structural integrity), so swift attention is key to both stemming water loss and preventing fissures from enlarging. Specialized leak detection companies can locate "mystery" seepages.
As the chlorine used in pools evaporates, it may contribute to local ozone pollution. Some of the measures detailed above can help cut down on chlorine use, as can employing an expert pool service which can establish the amount needed to keep your pool healthy and hygienic year-round, without overusing chemicals that create unnecessary pollution.