Tenaga Nasional Berhad (TNB) is engaged in the business of the generation, transmission, distribution and sale of electricity. The Company produces a range of energy sector-related products, such as distribution system transformers, power cables, optical ground wires, low voltage general cables, conductors, high voltage and gas insulated switchgears, circuit breakers and disconnectors. It also provides services and consultancy in managing and developing projects in district cooling systems, co-generation and building energy management, small renewal power, as well as repair and maintenance services for power plant equipment. On July 21, 2009, TNB and Sarawak Energy Berhad each acquired a 50% interest in Sime Darby Energy Sdn. Bhd.