THREE TREES FARM

The "SUNCATCHER" Revolution: EXECUTIVE SUMMARY

This solar hot water heater differs radically from the usual solar collector-storage tanks units with pump and multiple sensors that cost upwards of $ 2000 to build and install, and then require solar experts to maintain. Without the tax write-off available in California during the Brown administration, $2000 is not economically viable. Electric or LID gas heated water heaters have an annual energy cost of about $400. (You can check this at any water heater outlet by reading the EPA tags on the water heater.) With about 3/4 energy savings (see test data, page3), annual savings is only about $300 for electric and I-Pgas heated units, and about $132 for natural gas heated units. Our 50 gallon solar water heater, called "SUN CATCHER" sells for $970 (year 2000 in stock pricing) FOB Eugene, Oregon and can be installed and serviced by the same plumbers that install standard water heaters. This low price and service without solar heating expertise is possible because we have dispensed with the separate roof mounted collector as well as anti freeze fluid, pumps, sensors, associated plumbing, and other complications.

As you can see on the enclosed photo, the tank and collector are one and the same unit. No separate collector is required. The tank is its own collector. In addition to above cost saving, freeze up problems are drastically reduced, due to the large thermal mass of the warm water inside the tank. (Several years ago, a sudden one night freeze destroyed many solar water heaters in Northern California, including mine. That's what got me going on this. Incidentally, when I dismantled my collector, most of the 3/4 inch water pipes, after 15 years usage, were completely clogged up with mineral deposits due to the constant water circulation. This will not occur on the collector less unit proposed here, any more than on regular water heaters, because the 17 inch diameter tank is a also a very large pipe). To install the unit, give your local plumber a copy of installation instructions, below. Or install yourself, at your own risk.

"SUNCATCHER" DETAILED DESCRIPTION

The 'Sun catcher" solar water heater is made from a high quality glass lined electric water heater, complete with anode rod, electric heating elements and 1. 8 inch of polyurethane insulation.

About 1/3 of the outside of the tank as well as the insulation is removed. The bare steel surface of the tank is painted with a special absorptive coating. Then, the opening is covered by a curved "Lexan" window that is sealed against the tank. This insulates the open part of the tank. The thick polyurethane insulation remains around 2/3 of the tank as well as on both ends of the tank, so that about 3/4 of the original insulation remains on the tank. Thus, while the tank, equipped with reflectors, receives a lot of solar energy, very little energy escapes.

This energy conservation, coupled with the large thermal mass of the 50 gallon tank, results in a high degree of freeze protection when all water pipes to and from the tank are also insulated.

This eliminates the need for anti freeze, heat exchangers, pumps, solenoid valves and temperature sensors (and expenses, thermal losses, and maintenance thereof). In northern regions where weeks of freezing with little sun occurs, the hot water valve in your kitchen can be kept cracked open at night, to allow flow of about I gallon per hour, or an automatic freeze protection valve can be installed. This valve is available from Alten Co.,3788 Fabian way, Palo Alto, Ca 94303, Tel 415493- 4700 and costs about $70. Follow their instructions.

The "Suncatcher" water preheater comes complete with window and snorkel tube installed. In a separate box are the two 13 inch reflectors with the four predrilled braces and screws.

"SUNCATCHER" PERFORMANCE:

Performance on an average autumn day after servicing 4 people continuously for one week is as follows:

Ambient temp. average 72 F. Water inlet temperature 46 F. Reflectors and window very dusty. Not cleaned. Clear sky.

Time: 6.53 PM
Top water temp. 13 8 F
Middle temp. I I OF

Next morning 7:51
Top and middle of tank 92 F.
Ambient temp. 60 F

Performance can thus be summarized as follows:

Hot water is always taken from the top of the tank and is thus 138 F. Average temp. of water over a 24 hour period, fed to the inlet of the existing primary water heater is about 13 8 F+92 F /2 = 115 F. Cold water inlet to the water S012T water heater is 46 F.
Water heating required for 4 people without solar heating = 120 F - 46 F= 74 F.
Water heating with the 90 gallon solar heated preheater = 120 F - 115 F= 5 F

Energy savings with solar heating is (74 - 5) / 74 x I 00%= 93 %

This was taken in the autumn, on a sunny day. To account for rain and cloudy weather, I use 3/4 energy savings for Northern California.