10 Million Solar Roofs Act of 2010

10 Million Solar Roofs Act of 2010 - Directs the Secretary of Energy (DOE) to establish a program under which the Secretary shall provide competitive grants to states, Indian tribes, and local governments to provide rebates, loans, or other incentives to eligible participants for the purchase and installation of solar energy systems for properties located in the United States.

Requires the Secretary to implement criteria for awarding such grants that: (1) provides the maximum leverage of federal funds; (2) provides for the maximum deployment of solar energy; (3) ensures that grants are awarded to a diversity of geographic locations and recipients with different population sizes; (4) provides no less than 2% of the funds available to Indian tribes and consortia of Indian tribes; and (5) provides a preference for grant recipients that have established and maintained, or that agree to commit to establish and maintain, standards and policies to overcome barriers to distributed generation (including interconnection and net metering).

Authorizes the use of funds received to expand or establish a solar rebate program, a solar loan program, a solar performance-based incentive program, or another solar incentive program, solar deployment program or project, or innovative solar financing program as determined by the Secretary. Requires a grant recipient to: (1) certify that funds will be used to supplement, expand, or create new programs and to deploy an increased quantity of solar energy systems; and (2) submit to the Secretary an implementation plan that contains projections for solar energy systems deployment, data regarding the number of eligible participants that are assisted under existing applicable state and local programs, and projections for additional solar energy system deployment and the number of additional eligible participants covered.

Authorizes the Secretary to specify the type and capacity of solar energy system and type of deployment or incentive program for which the grant funds are made available. Makes each eligible entity receiving funds responsible for 20% of the amount of the provided funds.

Provides that a participant who receives a rebate under this Act shall not be eligible for a rebate for expenditures for installation of a renewable energy system in connection with a dwelling unit or small business under the Energy Policy Act of 2005.

Limits the aggregate value of the grants, rebates, and tax credits provided to an eligible participant to 50% of the cost to the purchaser of the purchase and installation.

Sets a goal of installing distributed solar energy systems on not fewer than 10 million properties located in the United States by December 31, 2021. Requires the Secretary to report to Congress on recommendations in achieving such goal.

Authorizes appropriations for FY2012-FY2021.