Solar Heating Systems for Your Pool
You can heat your pool using solar power. Your pool system already includes the pump, controller, and filter, along with PVC pipes that route the water flow. Simply break into the PVC line after the filter and run a couple of flex hoses (or PVC, if you prefer) to the solar collector panel, which you can lay out on the ground or set against a hill to achieve some tilt toward the sun.

A simple swimming pool solar-heating system.
When the valve is closed, water runs exclusively through the solar collector panel, heating the water. As you open the valve, less water flows through the collector panel. In this way, you can adjust how much heat is going into your pool.
Solar collector panels are available at most pool supply stores. You can get a 4 ft. x 20 ft. panel for around $220. Flex hoses cost around $35 apiece. Adaptors are sometimes necessary.
Here are some ways to run the system for best results:
Place the solar collector panel where it sees the most sunlight when the pool pump is running.
If you place the solar collector panel on your roof, try to minimize resistance to the water flow.
Keep the solar panel out of the wind as much as possible.
For best heating results, run the pool pump during the sunniest time of the day; running it longer will result in more heat in the pool.
If you want to use two or more solar collector panels, connect them in parallel.

Flexible solar collector panels that are designed to fit together in a parallel ganged arrangement reduce the overall water pressure while heating the same amount of water.
The general rule is to use a total collector surface area that's about half the surface area of your pool. But this varies quite a bit. Sizing your collector surface area depends on a number of factors:
The pump's running time: The longer it's on, the more heat you collect in the pool for a given collector size.
Pool location: If you have an aboveground pool, the heat loss is much greater. You need a collector with more surface area.
Solar potential when the pump is on: Note how your solar panels are oriented. How much sunlight do you get?
Shade: Cutting down Old Man Oak isn't much of an option if your blood is truly green. Otherwise, choose a larger collector.
Wind: If you have a lot of wind, your collectors will run inefficiently unless they are glazed.
Swimming pools cost a lot, upward of $30,000. If you don't have any kind of swimming pool heater, your useable season may be around four months of the year. If you install a swimming pool heating system, you can get eight months. This explains the popularity of pool heaters.
In a full-scale, professional-grade swimming pool solar system, when the pump is on, the controller decides whether to activate the solar collectors by measuring the temperature at the collectors and the temperature of the pool water. When heat's available at the collector, the motor valve opens, and the pump moves water up into the collectors and back down to the swimming pool.

When the controller deactivates the motor valve and no longer allows water to pump into the collectors, the vacuum breaker allows the system to purge itself of liquid.

Green Living Glossary
acid rain
A mild acidic solution that falls in rain or as dry particles caused when fossil fuel burning produces sulfur dioxide and nitrogen oxides. Acid rain has been linked to damaging effects on waterways and forests.

Green Living Glossary
active solar design
A strategy for designing high-performance, ultra-energy-efficient buildings. Active solar incorporates all the elements of a passive solar design with additional mechanical equipment, such as pumps or fans, to take advantage of the heat from the sun.

Green Living Glossary
alternative energy sources
Wind, hydro (water), biomass (fuel from natural material such as crops and agricultural waste), and solar power.

Green Living Glossary
biodegradable
Made from materials that will decay and break down into naturally occurring elements in a fairly short amount of time.

Green Living Glossary
biomass
Fuel made from natural material such as crops and agricultural waste.

Green Living Glossary
Bokashi
A Japanese term referring to a process of fermenting organic matter

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carbon emissions
Carbon released when many substances — particularly fossil fuels such as oil, gas, and coal — are burned by vehicles and planes; by the manufacturing processes of many consumer goods; and by the heating, cooling, and electricity for your home.

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carbon neutral
The state of reducing a person’s carbon emissions as much as possible and balancing the remaining carbon emissions by offsetting them with processes that consume carbon.

Green Living Glossary
carbon offsets; carbon credits
Paying for or participating in programs that reduce the carbon in the atmosphere. Purchased shares go toward reducing the same amount of environmental costs that an activity expends. Carbon offset programs or projects often involve tree planting because trees have a huge capacity to absorb carbon from the atmosphere. Other programs involve everything from supporting solar and wind power to replacing fossil fuel–burning stoves in developing countries with more sustainable energy sources.

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carcinogen
A cancer-causing substance.

Green Living Glossary
carpooling
Reducing the number of vehicles going to the same destination by having two or more people ride in the same vehicle. In most cases, carpoolers take turns being the driver and using their own vehicles.

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car-sharing
A system in which a person pays a fee that gives them access to a vehicle (or a pool of vehicles), usually parked in an easily accessible location. Car-sharing can eliminate the need for a personal vehicle.

Green Living Glossary
climate change; global warming
Changes in the concentrations of various gases in the atmosphere that are affecting the planet’s climate. Many scientists believe that the increase of carbon dioxide is a primary contributor to global warming, which occurs when gases trap warmth in the earth’s atmosphere instead of letting the atmosphere release it.

Green Living Glossary
compact fluorescent CFL bulbs
Fluorescent light bulbs that fit into a standard light bulb socket and use a fraction of the energy of their incandescent counterparts.

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compost
Decayed plants and other organic matter that breaks down into rich soil.

Green Living Glossary
core aerating
Poking small holes in the top few inches of lawn to encourage the flow of air, water, and nutrients.

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corporate social responsibility
Principles adopted by a business to make sure that its operations harm no one and instead benefit everyone around it and involved in it.

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daylighting
Bringing natural light into a home.

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ecosystem
A community of living organisms and nonliving materials.

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ecotourism
Sustainable and ethical travel in a natural environment.

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Energy Star
The federal government system for rating energy efficiency in appliances.

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Environmental Protection Agency EPA
Federal agency that regulates environmental laws.

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Fairtrade
System to ensure that workers and producers receive fair value for their products and that mandates sustainable practices in producing those products.

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food miles
The distance food travels from where it’s produced to the consumer.

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foodprint
The amount of land that various diets require to sustain them.

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fossil fuels
The energy-rich organic substances, traced back to the remains of organisms that lived 300 to 400 million years ago, that modern societies burn to provide power.

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geothermal
Energy within the Earth in the form of heat.

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greenhouse effect
The warming of the planet caused by gases in the atmosphere trapping the sun’s heat instead of letting it get through to space. This action is very similar to what happens in a greenhouse.

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greenhouse gases
Gases such as carbon dioxide, methane, and nitrous oxide produced by the burning and processing of fossil fuels and that contribute to global warming and acid rain.

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greywater
Water already used for washing, laundry, or showering that is appropriate for household functions from toilet flushing to watering plants.

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Leadership in Energy and Environmental Design LEED
A scoring system to rate how ecologically friendly buildings are.

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light shelves
White or light-colored horizontal fins above windows that bounce sunlight up onto the ceiling to bring it deeper into the room.

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light-emitting diode LED
A tiny semiconductor that emits light.

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natural gas
An energy source that burns cleaner than coal and oil but still releases carbon dioxide when it burns and methane during production, storage, and transportation.

Green Living Glossary
organic
Of living things; in food, grown without chemical fertilizers or pesticides or genetically modified organisms.

Green Living Glossary
passive solar design
Building design that takes advantage of the fact that the summer sun is higher than the winter sun. Overhangs shade the building from the summer sun and allow the lower winter sun to enter the building and heat it.

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petrochemicals
Chemicals derived from petroleum.

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phantom load; standby power
Energy drawn by a plugged-in appliance even when the appliance is turned off.

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plastic identification code
A triangle with a number from 1 to 7 inside indicating what type of plastic an item is made from.

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PV cell
A photovoltaic cell; a cell with a thin semiconductor that converts solar power into electricity.

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recycling
Collecting goods that have reached the end of their lives and processing them, their parts, or some of their parts, into the raw materials from which new goods are made.

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renewable energy
Energy from sources that cannot be used up, such as wind, water, and the sun.

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skylight
A rooftop window that brings in twice the light of a traditional window of the same size.

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solar panel
A panel containing cells that convert sunlight into electricity.

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sun tunnel
A passage that brings light into a room by bouncing sunlight through a small dome skylight on the roof connected to another skylight on the ceiling of the room. (Also known as a sun tube, sun pipe, and solar tube.)

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sustainable
Using natural resources in a way that allows for continued viability.

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thermal hole
An opening such as a window that leaks heat and air-conditioning energy.

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thermal mass
The ability of a material to absorb and store temperature.

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three Rs
The environmental practices of reducing consumption, reusing items, and recycling.

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top-dressing
Applying a light scattering of compost, other mulch, or sometimes fertilizer, over soil surfaces to add organic matter or nutrients without digging it in

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toxic waste
Disposed materials that can cause harm to people, animals, or the environment.

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vermicomposting
Composting with worms.

Green Living Glossary
xeriscaping
Landscaping for water conservation; a practice of garden planning and maintenance.