Scottish Power Limited is a vertically integrated energy company with its headquarters in Glasgow, Scotland, and a subsidiary of the Spanish utility Iberdrola. It is the Distribution Network Operator (DNO) for the central and southern Scotland and the Merseyside and North Wales regions. It is also the Transmission Owner (TO) for the in the south of Scotland . The company also supplies electricity and gas to homes and business around the United Kingdom and generates power for supply to the grid. It also owns PPM Energy in the United States.