Along with the emergence of three distinct ownership models (customer-owned, third-party-owned, and utility-owned), the U.S. photovoltaic (PV) market has grown, over the last ten years, at an average annual rate of approximately 70 percent, according to GTM Research.
The bulk of national solar growth has been in rooftop installations. More than 62,000 systems were installed in the U.S. in 2011, bringing the national cumulative total at the end of the year to over 203,000 distributed PV systems making up an installed capacity of almost 2,700 megawatts (AC).
A 30 percent federal investment tax credit (ITC), put in place for eight years in 2008, and net energy metering (NEM), in place in 43 states and D.C. that assures system owners are reimbursed at retail rates for the electricity they send to the grid, have both inclined home and business owners who can manage the rapidly falling upfront costs to make a commitment to rooftop solar. It makes up the largest segment of the PV solar market.