Federal Energy Management Amendments Act of 1991

Federal Energy Management Amendments Act of 1991 - Amends the National Energy Conservation Policy Act (NECPA) to set a deadline by which each Federal agency must: (1) install energy conservation measures in its Federal buildings with specified payback periods; (2) submit a list of projects to the Secretary of Energy (Secretary) which meet such payback criterion and indicate total energy and cost savings involved; and (3) have substantially completed at least 25 percent of such projects, or those projects that would account for 25 percent of total energy savings. Directs the Secretary to develop guidelines with respect to the selection of energy service contractors.

Requires: (1) each Federal agency that leases space in a building after January 1, 1994, to consider the energy efficiency of such building at the time of renewing of entering into a new lease; and (2) all government owned and leased space constructed after such date to meet model Federal building standards for energy efficiency. Sets forth specified procedures for implementation of energy conservation measures for each Federal agency.

Amends the Renewable Energy and Energy Efficiency Technology Competitiveness Act of 1989 to require the Secretary to solicit proposals for, and provide financial assistance to, joint ventures for the demonstration of fuel cells technology. Authorizes appropriations.

Amends the NECPA to require the Secretary to: (1) conduct a fuel cell systems demonstration program in Federal buildings; and (2) report to the Congress on the program's implementation. Authorizes appropriations.

Directs the Administrator of the Environmental Protection Agency to study the cost of environmental externalities associated with the use of different fuels and renewable and clean energy sources and technologies, and to prepare a report assigning monetary values to such externalities and describing the methodology used to obtain them. Requires submission of the report to specified congressional committees.