There is a movement among companies to use more renewable energy and less energy obtained from fossil fuels. Some are pledging to go “100% renewable”, with companies joining such groups as RE100, signing on to Corporate Renewable Energy Buyers’ Principles, and undertaking other initiatives. At least 150 large companies, including Apple, Facebook, and Google, among others, have set goals to rely exclusively on renewable energy. Many others have set goals to rely on substantial percentages of renewable energy in portions of their operations or in certain locations. There are many strategies that can be used in setting and fulfilling such goals, with differing effects on the energy environment. In addition to setting renewable energy goals, many companies report on how much renewable energy they currently use. This information is often conveyed in annually published sustainability reports or in publicly issued statements and news releases. Given that there is no legislative requirement for companies to use renewable energy, and that they set and meet their own goals, a question arises as to what companies mean by their statements about their renewable energy use. How should the public understand companies’ goals and progress? This report seeks to demystify the voluntary world of corporate renewable energy claims. Can differences in companies’ renewable energy strategies make any difference in the development and deployment of new renewable energy facilities? Is fossil fuel-based generation being displaced? Does a company that claims a certain renewable energy percentage actually use renewable energy in its operations?