The 140 MW Casecnan Hydroelectric Power Plant is part of the Casecnan Multi-purpose Project, a combined irrigation and hydroelectric power project by the National Irrigation Administration (NIA). It provides additional water sources to the Pantabangan reservoir from the Casecnan watershed by transporting excess water from the Casecnan and Taan Rivers through 30-meter weirs and 25 Km trans-basin tunnel into the reservoir.
The Power Plant is owned and operated by the California Energy Casecnan Water and Energy Company, Inc. (CEWEC) through a Build-Operate-Transfer (BOT) agreement with the NIA. NIA, on the other hand, is an Independent Power Producer (IPP) of the National Power Corporation (Napocor) through a Power Purchase Agreement (PPA).
The project was constructed at a cost of around US$600 Million and considered as one of the most expensive IPP power plants that were ever built in the Philippines in terms of USD per MW. The Plant started its commercial operation on April 5, 2002. It is located at the Pantabangan, Nueva Ecija, Philippines. The powerhouse is located underground.
Below if the Google Map location of the Plant;