It seems to me that the three most promising forms of clean renewable energy are solar, wind, and hydroelectric. In areas along major rivers such as the Mississippi, I would try to start public works projects to build hydroelectric dams. This could also help curb unemployment, which is above the national average in rural areas like that.
If possible I would also try to fund research that would lead to non-silicon solar panels, as silicon is also a limited resource which is already beginning to become scarce. Another option to look into is one that Sweden is pioneering. Sweden has actually begun using its nation's trash as a fuel to burn, with surprising efficiency. They even have begun to import trash from Norway, with Norway paying them for the service of trash removal. If America could gain that technology through some kind of partnership with Sweden, then we could begin doing the same; this would not only reduce our dependence on oil but also bring in revenue AND help the environment.