IAPMO USEC 1 – 2012 Uniform Solar Energy Code The advantages of a uniform solar energy code adopted by various jurisdictions have long been recognized by industry and government officials. The 2012 edition was developed through a true consensus process. Contributions to the content of the code were made from all sectors of the building environment, enforcing authority, installer/maintainer, labor, manufacturer, research/standard/testing laboratories, users and special experts.