Government documents are a useful source of information on energy and sustainability topics. U.S. federal government agencies such as the Department of Energy and the Environmental Protection Agency are actively engaged in energy-related research and they publish many documents in this area. The Library is a federal government Depository Library and therefore will have many government documents listed in Research@UWW.
Google Advanced Search
Try Google's Advanced Search to locate government documents. In the search box that says "Search within a site or domain" type .gov (that will find only web sites from government agencies).