The Maine Supreme Judicial Court has upheld the Public Utilities Commission’s budgeting for the state’s energy efficiency program.

On Thursday, the court turned back a challenge to the budget process that called for a decrease in financial support of Efficiency Maine, a state program that offers electricity, natural gas and other energy-efficiency measures to homeowners and businesses.

The Conservation Law Foundation had filed an appeal of the PUC’s budget decision, arguing that the PUC used an inappropriate analysis when it calculated the cost-benefit ratio of the energy efficiency program. CLF said the PUC calculations led to a $30 million underfunding of the program, which translated to $250 million in missed savings from energy-efficiency measures.

But a unanimous state supreme court said the law spelling out how the PUC can set the rates is ambiguous and the commission’s interpretation deserves “significant deference.” Based on the law and the available evidence, the court said, the PUC’s rate-setting was reasonable and the commission acted within its authority.

Sean Mahoney, a lawyer with CLF, said his organization’s major complaint in this case is that the PUC is supposed to base its budget decisions on saving Maine consumers and businesses the most money possible, and “they’re simply not doing it.”

In a separate case, the Conservation Law Foundation is challenging a PUC decision around solar incentives.

CORRECTION: This story was updated June 3 at 3:50 p.m. to remove references to a different lawsuit filed by the Conservation Law Foundation against the Public Utilities Commission, and to clarify an approximation of missed savings.