 The SEU model was developed by Dr. J. Byrne at the Center for Energy and Environmental Policy, University of Delaware.The Foundation for Renewable Energy and Environment (FREE) is implementing versions of the model.In the U.S., the SEU model was first implemented by the State of Delaware, followed by the District of Columbia, Sonoma County in California, the California Statewide Communities Development Authority (CSCDA), and the Pennsylvania Sustainable Energy Finance program.