California’s plan to get one-third of the state’s electricity from renewable sources by 2020 could cost $115 billion in new infrastructure, as per the findings of a study released by the California Public Utilities Commission (CPUC).

The plan could prove to be “costly and ambitious”, the report said.   

California law already requires the state’s big utilities to get 20% of their power from renewable sources by the end of 2010. There are also plans to raise the target to 33% by 2020. Legislation is pending in Sacramento to make that goal law.

If all that power was in place by 2020, new generation and transmission building costs would be $51.8 billion and electricity costs would rise to 15.8 cents per kilowatt hour from 13.2 cents in 2008, according to the report. Aiming for 33% renewables by 2020, would more than double capital costs to $114.5 billion and would increase state electricity costs to 16.9 cents per kilowatt hour, the report said.

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Read more: California Public Utilities Commission