Solar Power Your Home For Dummies

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How to Make Your Swimming Pool More Efficient

Boosting the efficiency of your swimming pool is an important first step in reducing your carbon footprint and moving toward a more sustainable lifestyle. Here's how to make your swimming pool energy efficient so that when you add solar, you get the most bang for your buck:

• Reduce bends in the piping: Sharp bends in the PVC piping slow down the flow and require more power to do the same job. Unfortunately, many pool installers completely fail this simple requirement. If your pipes are all over the place, rebuild the system. PVC is a cinch to work with.

• Make sure that all valves are working properly: If you have gate valves, replace them with ball valves, which are more efficient. Make sure that all ball valves are completely open or closed.

• Keep the filter clean: A dirty filter loads the pump, which costs a lot more power. If your filter is old, replace it. Cartridge filters are better than diatomaceous Earth.

• Install a smaller, higher efficiency pump, and run it less each day: Use the smallest, most efficient pump possible — 3/4 horsepower is usually sufficient. If your pump is a few years old and wasn't designed with enough capacity for solar panel use, buying a new one will probably be economical. Most people will find that they can run their pool pump for much less time and still achieve satisfactory cleanliness. Give it a try.

  A large power pump filters your pool water faster, and some people like that because it means you can run the pump less (which means you listen to it less). But here's the problem: If you're planning on putting up solar panels, the amount of heat they put into the pool is a function of how much time water is flowing through them; the quantity of water isn't as important. So if you have a large pump that moves water quickly, you're not optimizing your solar panels.

• Install windbreaks around your pool. Wind can increase evaporation 300 percent or more, which wastes a lot of energy, much more than you may think.

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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.

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. 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 above ground 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. 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.

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How to Use Radiant Heat Floor Systems

Radiant floor heat systems use solar power to heat water, which is then pumped through your home's floor. You can use solar-heated water to heat your home off-grid. Radiant heat, without solar, costs much less than forced-air heating for efficiency reasons.

Installing a radiant heat floor system is almost surely not a do-it-yourself project, but it merits elaboration because it's such a complete and effective way to use solar energy water heating. A snaking closed loop of metal or plastic tubing runs beneath your floor. When hot water flows through the tubing, the heat radiates upward through the floor and into the room.

When you supplement your radiant heat system with a solar water heater, you can drive your heating costs down to nearly nothing. Of course, sunshine isn't very reliable, particularly on the coldest nights when you most need heat, so you can't use solar heating exclusively; it can only be a supplement. But it can be very effective. Plus, it's also the most comfortable way to heat a home.

You can use any type of water heating system with a radiant floor system, but the capacity of hot water that you use goes up dramatically with a radiant heat floor system. So the attraction of a solar system also goes up dramatically, because you get much cheaper hot water per BTU.

At the very least, radiant heating reduces your carbon footprint. When you combine it with solar, the pollution savings can be impressive.

The engineering is complex, and the installation is clearly not for the faint of heart. There are technical problems, of course, but the systems have been in use for a long, long time. New technologies are making these the system of choice for a lot of homes.

Here's why: With conventional forced-air systems, hot air comes in through the vents and immediately rises to the ceiling. That's not where you want it, so you need to either pump in more heat than you really need (inefficiency) or use overhead fans to move the air back down (inefficiency). Moving air makes you feel colder, and you get stuck listening to blower noise as a big machine goes on and off all night. Furthermore, heated air dries out very fast, so your lips dry up, and your skin gets tight.

With radiant floor systems, there's no blower noise, wind chill is nonexistent, and you don't have to mess with HVAC filters. The big benefit is that the heat is in the room — the floor and furniture — not just the air. You can adjust your thermostat to a lower temperature in a radiant house and achieve the same comfort level because the floor and furniture are where the heat is. Where you set the thermostat is a question of comfort, not numerical temperature.

If you're planning on a room addition to your house, consider using a radiant floor in that room. Your existing HVAC system likely won't have enough capacity to heat an additional room. Adding a solar water heater to your house and using your domestic heater to heat the radiant floor in the addition works wonders, and it's usually cheaper than adding another small HVAC system.

You can also cool your house with radiant flooring. It doesn't work quite as well as heating, but if you have solar panels, you can use these at night to cool the water that's already in the closed loop of the radiant floor system. The reason the collectors will cool is simply because they have so much area, and the heat will escape into the cool, nighttime air. This is especially true if a breeze is blowing.