The revolving loan fund is often referred to as a green revolving fund, or GRF, when it is initiated on college and university campuses. These types of funds target projects that improve campus energy-efficiency, reduce resource use, and implement other projects and programs that fall under the category of sustainability. In recent years, GRFs have become increasingly popular on campuses in the United States. The funds operate and are managed by the university, with loans issued to university departments or campus groups.