Situated at Tap Shek Kok in Tuen Mun, Castle Peak Power Station (CPPS) is the largest coal fired power generating station in Hong Kong and occupies an area of 62 hectares with total capacity of 4,110 MW.

"A" Station, housing four generating units of 350MW each, was built between 1982 and 1985. To cope with increasing needs, "B" Station, which houses four larger units generating 677.5MW each, was commissioned in phases between 1985 and 1989. With a total investment of HK$20 billion, they were combined in 1993 to form CPPS, which is one of the largest coal-fired power stations in the world.

Whilst coal is used as the primary fuel source, the station design also allows oil to be used as an alternative. In 1996, two 677.5MW units were modified to burn natural gas as an additional energy source, making these two units unique with tri-fuel firing capability.

The numerous functional buildings are serviced from an extended site infrastructure and vary from basic ventilated equipment buildings to fully serviced air conditioned accommodation for administration offices, canteens, laboratory, computer installations, large fully equipped workshop, power plant simulator rooms and the central control building from which the station is operated.