Rooftop solar is wasting billions of dollars per year and isn't green according to a commentary in the Wall Street Journal. Utility lawyer Brian Potts contends in his opinion piece that the rooftop solar "craze" is hindering the growth of more cost-effective renewable power sources.
Potts cites a North Carolina State University report (backed by the DOE) that did find that installing a fully financed, average-size rooftop solar system would reduce energy costs for 93% of the single-family households in the 50 largest American cities today.
But the only reason these systems are currently cost-effective to consumers, Potts contends, is that they are heavily subsidized. The law forces utilities to buy solar power generated from the rooftops of homeowners and businesses at "two to three times more than it would cost to buy solar power from large, independently run solar plants."
Potts writes that large, utility-scale solar power plants can cost as little as five cents (or six cents without a subsidy) per kilowatt-hour to build and operate in the sunny Southwest. These plants are competitive with similarly sized fossil-fueled power plants. "But this efficiency is possible only if solar plants are large and located in sunny parts of the country."
He goes on to give reasons as to why we are paying more for the same sun: "Well-meaning—but ill-conceived—federal, state and local tax incentives for rooftop solar give back between 30% and 40% of the installation costs to the owner as a tax credit. But more problematic are hidden rate subsidies, the most significant of which is called net metering, which is available in 44 states."