A study by the University of Tennessee's Baker Center for Public Policy says that solar energy is subsidized at about the same rate as other energy sources.

The industry "is consistent with the less-than-smooth paths that many American industries have traveled as they entered the mainstream of commerce," the study said. It added that solar power was in a stage "where government incentives can be most critical in helping new energy technologies become significant sources of energy production."

The authors said they projected that solar energy development could add 67,700 jobs nationally by 2030.

A recent move to loosen California's green energy mandate was shot down by a state Assembly committee.

Gov. Jerry Brown signed a bill last year that requires utilities to get 33 percent of their electricity from renewable sources by 2020.

A proposal by Assemblyman David Valadao, R-Hanford, would have allowed utilities to include hydroelectric power from large-scale facilities when calculating their renewable energy percentage. That would have created an incentive to build new hydroelectric facilities, which could be constructed in the western United States; British Columbia, Alberta; or Baja California.

The bill would have been "a de facto repeal" of the existing regulations, according to an analysis of the bill prepared for the Assembly Committee on Natural Resources, because most major utilities already exceeded the 33 percent threshold if their existing hydroelectric power was included.