10 Million Solar Roofs and 10 Million Gallons of Solar Water Heating Act of 2010 - Requires the Secretary of Energy to establish a program to provide rebates for the purchase and installation of solar photovoltaic systems and solar water heating systems for residential and commercial properties in order to install over 10 years at least : (1) an additional 10 million solar systems with a cumulative capacity of at least 30,000 megawatts; and (2) an additional 200,000 solar water heating systems with a cumulative capacity of 10 million gallons. Establishes rebate eligibility criteria and the amount of rebates.