National Grid, 8302 Ditmas Ave, Brooklyn, NY 11236, US

National Grid is an international, London-based company that delivers electricity and natural gas. It serves more than 5 million customers in the Northeast. It has operations in Massachusetts, New Hampshire and Rhode Island and manages the electricity network on Long Island in New York under an agreement with the Long Island Power Authority (LIPA). The company is one of the largest distributors of natural gas in the Northeast. National Grid also owns over 4,000 megawatts of contracted electricity generation that provides power to over 1 million LIPA customers. It offers services to energy suppliers, technical and construction professionals, and landlords and property managers.