Irradiance, Inc. was founded in 2002 by Edward C. Kern, Jr., Ph.D. to manufacture the Rotating Shadowband Radionometer (RSR2), an instrument Dr. Kern and his collegues developed in 1991 while Dr. Kern was president of Ascension Technoloy, Inc. Ascension Technology was a startup company, spin-off from Massachusetts Institute of Technology's early solar photovoltaic power systems research and development projects. During the late 1980's and 1990's the company's focus was on grid-connected PV systems for residential and commercial building roof-top applications. Instrumentation was always a strong component during these early years as most grid-tied systems were then "experimental" in many ways and much needed to be learned about their performance and interconnection to utility grids. Ascension Technology produced and sold over 200 RSRs thorugh 1999. As president of Irradiance, Inc. Dr. Kern's prime focus is the development and deployment of the RSR2 although Irradiance occasionaly participates in consulting projects.