Computing has many potential 'green' applications including improving energy conservation, enhancing energy management, reducing carbon emissions, and improving environmental protection. The Computer Science and Telecommunications Board of the National Research Council will appoint an ad hoc study committee to plan and conduct a workshop involving approximately 40 experts that will explore research themes and specific research opportunities that could advance these energy and environmental objectives and also result in advances in computer science and consider research modalities, with a focus on applicable computational techniques and long-term research opportunities. In phase 2, a consensus report will be prepared that identifies promising research opportunities, catalogs applicable computational techniques, lays out an overall framework for 'green' computing research, and recommends long-term research objectives and directions.