Allegheny Energy (NYSE: AYE) is a traditional public utility based in the Pittsburgh suburb of Greensburg. It services communities in Western Pennsylvania, Western Maryland, Northern West Virginia, Northwest Virginia. The company is the region's biggest energy supplier, providing power to over 1.5 million customers, including many in suburban Pittsburgh, where it battles its chief rival, Duquesne Light for customers. An unusually large amount, about 95%, of the power produced by the company comes from coal generators. Several of these are brown-coal fired, leading to concern by environmental groups over Allegheny Energy's environmental impact.