The Maryland legislature Friday, March 29 rejected a bill that would have removed so-called “black liquor,” a paper mill byproduct, from qualifying as a renewable fuel. The bill, which had passed the Senate easily, failed in a House committee in the face of lobbying by labor unions and paper companies.

The state’s renewable portfolio standard requires Maryland utilities to generate increasing amounts of electricity from renewable sources or purchase renewable credits from other companies doing so. The Washington Post reported that most of the payments for credits have been going not to wind or solar projects but to seven paper mills that use black liquor as fuel. More in The Washington Post.