TACLOBAN CITY, PHILIPPINES — Energy Development Corp. (EDC) is evaluating a ₱70-billion redevelopment plan for its aging geothermal infrastructure in Leyte, aimed at adding 200 to 400 megawatts (MW) of new generating capacity and extending the operational lifespan of the province's primary renewable energy reserves.
Upper Mahiao Decommissioning and Facility Modernization
The proposed project centers on replacing outdated generation units in Kananga with modern, highly efficient technology:
Phased Decommissioning: The existing 125-MW Upper Mahiao geothermal plant, commissioned in 1996 under a build-operate-transfer scheme and acquired by EDC in 2006, will begin phased decommissioning in 2026, heading toward full retirement by 2029 due to age and declining efficiency.
Efficiency Improvements: The new facility will utilize modern geothermal technologies to extract significantly higher electrical output from existing underground reservoirs using lower volumes of steam, extending field operations for an estimated 40 to 50 years.
Regulatory Timeline: EDC has formally submitted its proposal to the Department of Energy (DOE), targeting regulatory approvals in 2027 to prepare for full commercial operations between 2030 and 2031.
Global Scale: EDC President and Chief Operating Officer Jerome Cainglet highlighted during the Net Zero Conference in Manila that the project represents one of the largest geothermal redevelopment initiatives worldwide.
Regional Infrastructure Context and Local Revenue Impact
The redevelopment builds upon more than four decades of continuous geothermal power generation across the Tongonan geothermal field:
Historical Field Development: Spanning over 107,000 hectares across Kananga and Ormoc City, the Tongonan field represents the world's largest wet-steam geothermal resource. It currently supports the 123-MW Tongonan 1 plant alongside the Unified Leyte facilities (Malitbog, Mahanagdong, and Upper Mahiao).
Visayas Grid Reliability: EDC Vice Chairman and CEO Francis Giles Puno noted that the additional 200 to 400 MW capacity will enhance baseload supply stability across the Visayas grid.
LGU Royalty Revenues: Host municipalities, including Kananga and Ormoc City, stand to gain increased local revenue streams. Under existing regulations, host LGUs receive ₱0.03 per kilowatt-hour generated within their corporate jurisdictions.
