TAIPEI (Taiwan News) — Academia Sinica said that a test well in Yilan County's Yuanshan Township has confirmed a high-potential geothermal site that could support green energy development.
Drilled in collaboration with CPC Corporation, the well is Taiwan’s first deep geothermal exploration site. The research team reported that it reached nearly 4,000 meters underground, with temperatures at the bottom approaching 150 C, confirming an upwelling heat source.
This demonstrates that the northern Yilan Plain has significant deep geothermal potential. The team hopes industry, government, and academia can collaborate to make deep geothermal a key pillar of Taiwan’s green energy transition.
Lee Jian-cheng (李建成), head of Taiwan's national geothermal research program, recalled that at 3,000 meters depth, the temperature was still below 100 C, raising initial concern. Temperatures then rose rapidly beyond 3,500 meters, increasing roughly 90 C per kilometer, before nearing 150 C at the well bottom.
Lee added that the drilling site is likely close to the center of a high-temperature heat source, which may reach exploitable temperatures as shallow as 3,000 meters underground.
Analyses of CPC drilling data show that the lower formations have favorable geological conditions suitable for a low-seismic-risk hydraulic stimulation method. This method effectively guides hot-water flow paths, creating optimal conditions for geothermal development.
Chen Yu-Kao (陳于高), executive secretary of Academia Sinica’s Center for Sustainability Science, said that typically three to five test wells are needed to successfully develop a geothermal field. The Yilan well’s results confirm the area’s potential and justify additional wells to map the three-dimensional structure of geothermal upwelling for future heat extraction and project planning.
The well has been temporarily converted into a monitoring well, using distributed fiber-optic laser sensing to track underground heat dynamics and rock characteristics. The team aims to use this data to locate high-temperature rock layers, map their distribution, track heat-source movement, and assess whether conventional geothermal or enhanced geothermal systems would be most efficient for future power plant development.
