That was probably an exaggeration. However, just in case, now that Perry has been confirmed for his new position, for him or for anyone else, a good place to start is AllGov's page about the department here. For more information about 14 of the Department of Energy's offices and programs, start here.

Here is your AllGov introduction to the Department of Energy:

The Department of Energy (DOE) is responsible for advancing the national, economic and energy security of the United States through the implementation of policies regarding nuclear power, fossil fuels, and alternative energy sources. The DOE promotes scientific and technological innovation in all of the aforementioned energy sectors and is charged with the environmental cleanup of the national nuclear weapons complex. One of its key duties is the formulation and implementation of the National Energy Policy. This comprehensive and wide ranging document covers energy challenges facing the US;  impacts of high energy prices; protecting America's environment; increasing energy conservation and efficiency; increasing domestic energy supplies; increasing America's use of renewable and alternative energy; America's energy infrastructure; and enhancing national energy security and international relations.