Solar Water Heating Systems

NOTICE: Effective July 1, 2021, the ICC-SRCC OG-300 certification program will formally adopt the 2020 edition of the ICC 900/SRCC 300 standard. After that date, all new OG-300 applications will be required to comply with ICC 900/SRCC 300-2020. Until that date, applicants may choose to use the 2015 or the 2020 version of the standard. Contact us for more information.

The ICC-SRCC OG-300 Solar Water Heating System Certification Program provides proof of compliance for solar water heating systems to the current ICC 901/SRCC 300 standard. This standard is widely referenced by building codes, standards and incentive programs throughout North America. U.S. Federal tax credits, EPA ENERGY STAR® programs, the California Energy Code (Title 24), National Green Building Standard (ICC 700) and many others rely on OG-300 certifications.

OG-300 certification not only ensures that solar water heaters meet minimum requirements for safety and durability, but also provides objective energy ratings customized for nearly 200 locations throughout North America. This allows the performance of different models and types of solar water heaters to be compared directly and consistently. OG-300 performance ratings are used by many incentive programs and tax credits seeking to save energy and cut emissions.

Engineers and designers use OG-300 performance ratings with a variety of modeling tools to integrate solar water heaters into green buildings. For consumers, designers and architects, the ICC-SRCC OG-300 directory is often their first stop to find and compare solar water heaters to meet their project needs.


ICC-SRCC OG-300 is the most widely recognized certification program for solar water heaters in North America, ensuring that certified products can be sold, incentivized and installed virtually anywhere in the U.S.
ICC-SRCC has been offering solar thermal certifications for over 3 decades. Our staff is solar thermal experts. We know your products and we know OG-300 because we created it.
High-quality computer modeling provides estimates of system performance and the energy savings in many different climates. All OG-300 certified systems are modeled using the same conditions so users can easily get an unbiased comparison.
OG-300 certification involves more than just modeling. ICC-SRCC's engineers review systems to be sure they meet all requirements of the ICC 900/SRCC 300 Standard, providing assurance that they meet comprehensive safety, durability and minimum performance requirements – as required by most building codes in the U.S., like the International Building Code (IBC) and International Residential Code (IRC).
OG-300 systems are provided with a certificate of compliance, readily available on the ICC-SRCC website, www.solar-rating.org. They feature certified performance ratings, system details and a complete schematic of the approved system. See for yourself on our online listing directory.


To learn more about ICC-SRCC's OG-300 certification program, click on any of the links provided, or contact us at srcc@solar-rating.org.

Apply for OG-300 Certification
Mark of Conformity