How Should You Insulate Your Storage Tank

Keeping heat in a hot water storage tank is like trying to keep a leaky inner tube pumped up. No matter how hard you try, you're constantly fighting a losing battle. Some heat will always escape. How much insulation is enough It's theoretically impossible to over-insulate a solar hot water system, but here are some minimums There should be at least 3-1 2 inches of fiberglass insulation or its equivalent behind the absorber plate in the solar collector, as we already know. There should be at...

What Should Your Storage Tank Do Besides Store Heat

Let's discuss some terms you'll want to be familiar with as you design your solar heater People who work with solar heating say that a system is down whenever the sun is not shining and all the stored solar energy has been used up. In other words, down means the system is just not producing. The down point is reached when hot water can't be taken from the storage tank any longer because it's not hot enough. At this point we either go without a hot shower or have a set-up that allows a...

Storing and Protecting Your Solar Energy

We know how to collect energy from the sun. Our problem now is to store it effectively. Solar energy, as everyone knows, is not constant. We have seasonal changes and clouds, which naturally affect the sun's intensity, and we also have night. One reason why heating domestic hot water with the sun makes so much sense is because water itself is such an excellent storage medium. In fact, if you're going to transport or store solar energy, using water or at least a fluid containing water is one of...

How Much Hot Water Do We

Coil Heat Exchanger Schematic

Americans use and waste appalling amounts of hot water. People in other parts of the world just can't believe us. Motel owners in E urope complain bitterly about how tourists from the United States increase their fuel bills and overload their septic systems. We're spoiled. We squander water just the way we've squandered many of our other resources. John Murphy, in the Homeowner's Energy Guide, says that we use up hot water in approximately this way Every time we take a shower we use about 10...

Can Pool Water be Heated with Solar Collector Panels

Solar Absorber Plate Design

For some reason, cheaper solar collectors designed specifically for swimming pools are called heating panels rather than collectors even though they work on the same principle. Regular collectors the type we've been discussing throughout this book can be used. But it's a little like taking a Ferrari to pick up a load of 2 x 4's at the lumber yard. Figure 95. Using a little imagination, designers at Parallax in Hinesburg, Vermont, have built a concrete pool deck that doubles as a flat plate...

A

Exploded View Solar Collector

The difference between figures A and B is in the curvature of the reflecting surfaces. A is what is called a short-focus collector because the focal point is close to the reflector. It doesn't need to face the sun as exactly as B, but its more rounded mirror makes it more difficult to build. B, the long-focus collector, is easier to make, but harder to operate precisely. haze or cloud cover. Third, focusing collectors are expensive to buy and complicated to build. Locating that...

How Do You Put the Plumbing Together

Jigs Pictures Solar Power Plant

Connections between pieces of copper tubing are made with special fittings and solder, as everyone knows. Plumbers, fix-it men and do-it-yourselfers call it sweating joints. Copper pipe, of course, is soft and easy to cut. You can use either a hacksaw or a small tube cutter which leaves you with a perfectly square end. To sweat a joint you'll need four things 1 some steel wool or emery paper, 2 flux, which is a paste that looks like Vaseline, 3 solder wire, and 4 a heat source usually a propane...

Info

After Wilson Clark, Energy for Survival After Wilson Clark, Energy for Survival Table 4. This simple table shows the average amount of solar energy that falls in a square-mile area in selected parts of the United States. In this case, the energy is expressed as megawatts 1,000 kilowatts. A typical modern electrical power plant only generates a few hundred megawatts a day. Some of the largest manage to put out 1,000 per day. horse-power hours of solar energy fell on Mother Earth. In electrical...

How Long Does it Take to Pay Off a Solar Water Heater

We have already figured out that it can cost a family of 5 about 348.43 a year to heat water to 140 degrees Fahrenheit with electricity. If this same family could build a solar water heating system for 750 and that system were 75 efficient, they would be saving 261.32 a year in electrical utility costs 348.43 x .75 261.32 . Dividing this figure into 750, we can compute that it will take 2.8 years to pay for the system with inflation it may take even less time . If the family spent 2,500 to have...

Appendix C Absorber Plate Manufacturers

Davis, CA 95616 David Springer phone 916 756-4558 Product Name Absorber Plate Berry Solar Products Woodbridge at Main P.O. Box 327 Edicon, NJ 08817 Calvin C. Beatty phone 201 549-3800 Product Name Absorber Panels Burton Z. Chertol phone 516 643-6660 Kennecott Copper Corp. 128 Spring St Lexington, MA 02173 Phone 617 862-8268 Product Name Terra-Light Solar Absorber Plate Product Name Roll-Bond Absorber Plates Product Name Absorber Plates C-18 and C-6 Robert S....

Complete Solar Hot Water Systems

Cole Solar Systems 440A East St Elmos Rd. Austin, TX 78745 Warren Cole phone 512 444-2565 System Name Domestic Hot Water System 12A or 28D Columbia Chase Solar Energy Div. 55 High St Holbrook, MA 02343 Walter H. Barret phone 617 767-0513 System Names Columbia Domestic Hot Water System Columbia Direct Exchange Domestic Hot Water Kit El Camino Solar Systems 5330 Debbie Lane Santa Barbara, CA 93111 Allen K. Cooper phone 805 964-8676 System Name Sunspot Solar Water Heating System Energy...

How Should You Select a Tank

Spend some time shopping for your storage tank. They vary a lot in price, quality, and in the amount of insulation they have. Used tanks of various kinds may offer some attractive possibilities. Look for old water tanks or larger propane tanks if you can only spend a little money. The tank will need to stand a lot of pressure as much as 60 pounds per square inch psi . Sixty psi is normal in many homes and municipal systems. So check the tank's structure pretty thoroughly, particularly joints or...

How Does Sunlight Hit the Earth

Insolation And Earth Diagram

One of the things you will have to consider as you make decisions about your own involvement with solar energy, is the latitude of your home. You probably don't need to be told that the farther you go from the equator that imaginary line that slicas the globe into a top half and a bottom half the weaker the sun's energy becomes. What many people don't realize is that the more horizontal lines parallels of latitude there are on the map between you and the equator, the farther sunlight has to...

What About Antifreeze

Don't use ordinary and poisonous automotive antifreeze. The very best antifreeze for solar collectors is something called non-toxic propylene glycol. You should be able to find it in any plumbing supply store. If not, order Sunsol 60 from Sunworks, Box 1004, New Haven, Connecticut 06508. Also see appendix. Five gallons should be more than enough for a two to three-collector system in a normal house. You'll need just about 1 2 gallon of unmixed propylene glycol for each 24-square-foot collec...

How Does a Solar Pool Heater Work

Solar Circuit Air Vent

In a fairly sophisticated solar pool system, water is pumped out of the pool, through the strainer, and through the filter. After the filter it passes through a check valve. This check valve is more than just an option. Its purpose is to keep water that's draining out of the panels from back-washing the filter Figure 99 . Once it has passed through the one-way check, the pool water reaches a critical tee. This tee separates the upper panel loop from the ordinary circulation loop. When the pool...

What Are Focusing Solar Collectors

Magnifying Glass Heater

As we all know, much of our English language has evolved from the ancient Greek, and many English words have Greek parts. So any word that has the prefix helio- probably has something to do with the sun. A helioelectrical process is a way of converting sunlight to electricity something we're just learning to do efficiently. Photosynthesis, mentioned in the last chapter, is an example of a Focusing collectors or solar concentrators as they're sometimes called...

How Should a Solar Collector Be Tilted

How Make Solar Pool Heater

Supports Mylar, Tediar or Kalwall Glazing Supports Mylar, Tediar or Kalwall Glazing Don't confuse orientation with tilt Orientation describes the direction the panel faces, while tilt describes its angle of inclination. Tilt is a little more touchy. Ideally the collector should be at right angles 90 degrees to incoming solar rays, but this can't happen all the time if the panel stays in a fixed position. After all, the difference between the sun's altitude in June and its altitude in December...

How Much Do Swimming Pool Covers Help

Swimming Pool Safety

An opaque or transparent swimming pool cover which will transmit solar radiation to the water can give your pool another 10 degrees of natural storage capacity. This means that if a free-floating cover with pockets of trapped air is stretched over the pool at night and whenever no one is swimming , we can expect tbe water temperature to stay at up to 20 degrees above the surrounding air Figure 94 . Insulating pool blankets, as they're called, pass about 85 percent of the light that hits them...

Appendix G Control System Manufacturers

Product Name Solar Controls AD-101 and AD-102 Aqueduct Component Group 1537 Pontius Ave. Los Angeles, CA 90025 Herman Wertheimer phone 213 479-3911 Product Name Automatic Row Control Valve UP-050 through UP-200 Contemporary Systems, Inc. 68 Charlonne St Jaffrey, NH 03452 John Christopher phone 603 532-7972 Product Name LCU-110 Digital Logic Control Unit Donald F. Dekold phone 904 372-6009 Product Name Solar Differential Controllers del sol Control Corp. 11914 U.S. 1 Juno, FL 33408 Rodney E....

Appendix F Liquid Flat Plate Collector Manufacturers

Box 250 Concord, MA 01742 Stephen V. Santoro phone 617 369-4111 Product Name Sunwave 420 Solar Collector All Sunpower, Inc. 10400 S.W. 187th SL Miami, FL 33157 E.M. Kramer phone 305 233-2224 Product Name All Sunpower 3784 Product Name Solar Collector Panels 200G Ametek, Inc., Power Systems Group 1 Spring Ave. Hatfield, PA 19440 Frank W. Gilleland phone 215 822-2971 Product Name Copper Solar Collector Burton Z. Chertok phone 516 643-6660 Product Name Burton Solar...

How Do the Seasons Affect Insolation

Hour Angle Sunrise For Tilted Surface

Explained was that the earth moves around the sun at an average speed of about 18.5 miles a second, and that on December 21 we are about 89.8 million miles from the sun, but 95.9 million miles from the sun on June 21. This is because the sun isn't always in the exact center of our orbit. Our childish logic might have told us that it should be the other way around if we were closer in December, it should be warmer then summer What we also may not have understood as very young children, but could...

How Should You Select Glazing

Kalwall Beam

An absorber plate, no matter how good it is, can't make use of any radiation that doesn't get to it. So a glazing's ability to let light through is of number-one importance. To be really effective, a glazing material should be at least 88 to 92 translucent Most plastic glazings don't have the transmit-tance or heat-enduring properties of glass. In some cases, they get destroyed because ultraviolet rays break them down in a relatively short time. Others seem to hold up well enough, but certain...

How Much Do Solar Reflectors Help

Reflector panels which bounce rays back onto a collector should reduce the amount of collector surface you need. In fact, a small collector can receive more radiation than a much bigger one if it's helped by properly arranged reflection surfaces. Good reflectors should boost the performance of any flat plate collector by at least 25 Figure 44 . Figure 44. Sometimes banks of solar collectors and reflector panels can be made to work in combination. Reflectors can increase the performance of flat...

What About Painting the Absorber Plate

The absorber plate needs to be black to absorb much solar radiation, as you already know. There are special selective paints developed specifically for solar systems. These are expensive because they're so special, but they allow shortwave radiation to be absorbed by the plate, and at the same time retard re radiation of longer wave-length rays. Unfortunately some of these selective paints can't be easily applied at home, so we have to find substitutes. Shiny black paint, of course, reflects...

How Can You Build Your Own Absorber Plate

Season Solar Water Heater

Some ambitious and highly-skilled types will surely choose to build their own absorbers. Several good plans have been published lately, and even though they require a lot of picky labor, the final products work pretty well. One detailed set of instructions is put out by the Brace Research Institute near Montreal, the world-renowned center for studying intermediate technology. Their plans call for a sheet of galvanized corrugated steel roofing riveted to a flat sheet that is slightly larger. The...