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Domestic Hot Water
Certification
 
 

Domestic Hot Water-System Certification

Solar Rating Certification CorporationThe Solar Rating and Certification Corporation (SRCC) is a non-profit organization whose primary purpose is to establish National Rating Standards for solar energy equipment. This is the only national certification program for solar energy products.

The SRCC provides a one-time certification, national recognition, product credibility and standardized comparisons of solar energy products. The SRCC state-of-the-art rating system is a mechanism to develop consumer confidence, and a rational criterion for tax credit qualification and other solar incentive programs.

The SRCC uses a computer model to estimate the thermal performance of a solar water heating systems under specified conditions. These ratings are based on conditions similar to the ones defined by the U.S. Department of Energy for testing conventional water heaters. The annual performance listed is an estimate of how solar water heaters could perform over a whole year in a specific location. Keep in mind that these ratings are only estimates based on test conditions and that your actual performance will vary depending on your hot water usage and actual weather conditions.

Guidelines for the SRCC List of Certified Systems Annual Projected Savings

1) Go the SRCC web site at www.solar-rating.org

Zone 7* = San Diego Area
Zone 9*= South Ventura and North Los Angeles County Area
Zone 12* = Central Mid-State Area
Zone 16* = North Eastern and Central Eastern California Area

2) The test results are based on a standard 50 gallon conventional electric water heater that would consume 4,100 kilowatt hours (kWh) per year. And a standard 50 gallon gas water heater that would consume 205 therms (including delivered energy and losses).

3) The key test result is the last column on the right labeled: Energy Savings. This is the estimated annual performance of the system. This represents the amount of energy produced by the solar system, that did not have to be provided by the conventional water heater.

4) Example: If a 50 gallon electric water heater consumes 4100 kWh and the Energy Savings is 3000 kWh then from these estimates the solar system could provide 73% of your projected annual hot water needs.

In the case of a 50 gallon gas water heater, if it consumes 205 therms and the projected Energy Savings is 150 Therms then from these estimates the solar system could provide 73% of your projected annual hot water needs.

5) Important Key Point. The projected savings is determined by how the system is sized based on the household demand-this is the number of people using the system. The Department of Energy projects about 15-18 gallons of hot water per person per day. If the system is sized based on a high demand criteria you will have more solar hot water to offset use of the conventional water heater. We have found that 20 gallons of hot water, per person per day is a good projection in sizing the system. This also determines the size of the solar storage tank. For example: based on a family of 4 with a projected demand of 20 gallons of hot water per person per day, the projected size of the solar storage tank would be 80 gallons.

6) Please note these estimates are based on test conditions and your actual performance will vary depending upon hot water usage and available solar energy.

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