Solar Power

SRCC Rates Solar Water Heaters
for Three Montana Cities

Estimated Annual Performance of OG-300 Certified Solar Water Heating Systems In Billings, Helena and Missoula, Montana

The non-profit Solar Rating and Certification Corporation (SRCC) develops and implements certification programs and national rating standards for solar energy equipment. The SRCC was incorporated in October 1980 as an independent third-party certification agency. It is governed by a 12-member board of directors with representation from the public and private sectors. It is the only national certification program established solely for solar energy products. It is also the only national certification organization whose programs are the direct result of combined efforts of state organizations involved in the administration of standards and an industry association.

The combined programs of the Solar Rating and Certification Corporation provide onetime certification, national recognition, product credibility, and standardized comparisons of solar energy products. The SRCC programs serve three primary constituencies: the solar energy industry, solar consumers, and state and federal regulatory bodies. All three constituencies benefit from the SRCC programs by obtaining a national state-of-the-art rating system, a mechanism to develop consumer confidence, and a rational and defensible criterion for tax credit qualification and other solar incentive programs.

The OG-300 certification program for solar water heating, systems was established in 1992. It integrates results of collector tests and system tests with evaluations against minimum standards of system durability, reliability, safety and operation, as well as factors affecting total system design, installation, maintenance and service. A copy of the certification requirements is available from SRCC.

Performance Estimation Procedures

SRCC uses a computer model to estimate the thermal performance of solar water heating systems under specified conditions. A separate computer model for each system is developed from test data on some of the system components, manufacturer’s literature on the others, and theoretical calculations. The SRCC rating calculated using the computer model is called the Solar Energy Factor. It is published in a directory and in a summary booklet. These ratings are based on conditions similar to the ones defined by the U.S. Department of Energy for testing conventional water heaters. These conditions describe hot water usage for a single day. Keep in mind that these ratings are only estimates based on an assumed set of operating conditions and that your actual performance will vary depending, your hot water usage pattern and actual weather conditions.

The SRCC rated the annual performance of OG-300 certified systems in three Montana cities—Billings, Helena, and Missoula. Check below to download the performance reports from those three cities. The estimated annual performance indicators given in the reports are different from the SRCC ratings and are not directly comparable. The annual performance listed in the reports was developed to provide an estimate of how solar water heaters could perform over a whole year in a specific location. The SRCC rating estimates the performance of the systems under "rating" conditions. Keep in mind that these ratings are only estimates.

Estimated annual performance of OG-300 certified solar water heating systems in:

Billings (678KB PDF)

Helena (664KB PDF)

Missoula (663KB PDF)

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Solar Rating and Certification Corporation
The combined programs of the Solar Rating and Certification Corporation (SRCC) provide one-time certification, national recognition, product credibility, and standardized comparisons of solar energy products. The SRCC programs serve three primary constituencies: the solar energy industry, solar consumers, and state and federal regulatory bodies. All three constituencies benefit from the SRCC programs by obtaining a national state-of-the-art rating system, a mechanism to develop consumer confidence, and rational and defensible criteria for tax credit qualification and other solar incentive programs.

http://www.solar-rating.org/default.htm