for the trade association Edison Electric Institute stated that distributed generation systems, like rooftop solar, present unique challenges to the future of electric utilities. Utilities in the United States have led a largely unsuccessful campaign to eliminate net metering. Benefits Renewable advocates point out that while distributed solar and other energy efficiency measures do pose a challenge to electric utilities' existing business model, the benefits of distributed generation outweigh the costs, and those benefits are shared by all ratepayers. Grid benefits of private distributed solar investment include reduced need for centralizing power plants and reduced strain on the utility grid. They also point out that, as a cornerstone policy enabling the growth of rooftop solar, net metering creates a host of societal benefits for all ratepayers that are generally not accounted for by the utility analysis, including: public health benefits, employment and downstream economic effects, market price impacts, grid security benefits, and water savings. An independent report conducted by the consulting firm Crossborder Energy found that the benefits of California's net metering program outweigh the costs to ratepayers. Those net benefits will amount to more than US$92 million annually upon the completion of the current net metering program. A 2012 report on the cost of net metering in the State of California, commissioned by the California Public Utilities Commission (CPUC), showed that those customers without distributed generation systems will pay US$287 in additional costs to use and maintain the grid every year by 2020. The report also showed the net cost will amount to US$1.1 billion by 2020. Notably, the same report found that solar customers do pay more on their power bills than what it costs the utility to serve them (Table 5, page 10: average 103% of their cost of service across the three major utilities in 2011). Drawbacks Many electric utilities state that owners of generation systems do not pay the full cost of service to use the grid, thus shifting their share of the cost onto customers without distributed generation systems. Most owners of rooftop solar or other types of distributed generation systems still rely on the grid to receive electricity from utilities at night or when their systems cannot generate sufficient power. A 2014 report funded by the Institute for Electric Innovation claims that net metering in California produces excessively large subsidies for typical residential rooftop solar photovoltaic (PV) facilities. These subsidies must then be