 They then passed the Renewable Energy Law and integrated the 100,000 roofs program into it in 2004. The Renewable Energy Law, REL, mandated that for the next 10 years, the power company had to buy power back from those homeowners at a level substantially above the going rate so that the homeowners' income from the solar panels would equal their loan payments on the panels and would also represent the actual cost to the power company to generate that amount of power by building a new nuclear power plant.