A new court ruling said the Arizona Corporation Commission shouldn't have approved an electric generation project's planned use of power generated by a trash incinerator to qualify as renewable energy.

The ruling said the commission erred and abused its discretion in deciding to give renewable energy credits to the Mohave Electric Cooperative for the project planned near Surprise, Ariz. by the Reclamation Power Group.

Corporation Commission spokeswoman Rebecca Wilder said it may be some time before the commission decides how to respond to the ruling Tuesday by Judge Crane McClennen of Maricopa County Superior Court.

The Sierra Club argued that burning trash to produce power was not a use intended under Arizona's renewable energy standard, while the commission argued that its decision was entitled to deference to the court.