Renewable Energy Investment Act of 2005

Renewable Energy Investment Act of 2005 - Amends the Public Utility Regulatory Policies Act of 1978 to require retail electric suppliers to submit to the Secretary of Energy renewable energy credits in an amount equal to the required annual percentage of the retail electric supplier's total amount of kilowatt-hours of non-hydropower electricity sold to retail consumers during the previous calendar year (excluding incremental hydropower).

States that a renewable energy credit that is not used to satisfy the minimum requirement for that year may be carried over for use within the next two years.

Specifies a schedule of the minimum percentage of renewable energy sources that must be used to generate the total amount of non-hydropower electricity sold by each retail electric supplier during a calendar year (excluding incremental hydropower).

Directs the Secretary to: (1) establish a program to issue, monitor the sale or exchange of, and track renewable energy credits; and (2) make funds available under this Act to State energy agencies for grant programs for renewable energy research and development, and for loan guarantees to encourage construction of renewable energy facilities.