This bill establishes a U.S. Green Bank that provides financial support to assist regional, state, and local institutions finance: (1) clean energy (e.g., solar or wind energy) projects, or (2) energy efficiency projects that reduce energy use or substantially reduce greenhouse gas emissions. The Department of the Treasury must issue green bonds to provide the bank with: (1) an initial capitalization of $10 billion; and (2) additional capitalization, upon the bank's request, of no more than $50 billion in aggregate at any one time. The bill also establishes in the Treasury a revolving Green Bank Establishment Fund.