EDC to upgrade Leyte geothermal plants with US tech

It seeks to boost efficiency and sustainability and extend plant life.

Energy Development Corp. (EDC) is planning major upgrades to its geothermal power facilities in Leyte, Philippines, inspired by the technology used in The Geysers geothermal plants in California.

The initiative aims to improve efficiency, extend plant life, and ensure sustainable operations. The upgrades will be based on benchmarking initiatives with American energy company Calpine Corp.

“We will install a wellhead washing system, rock catcher, steam washing, and an additional demister,” Teodulfo Troyo, head of EDC’s Leyte site, told Asian Power. Combined, these deliver purified, high-quality steam that removes impurities and helps ensure efficient and reliable operation of the steam turbines.

A subsidiary of First Gen Corporation, EDC operates three geothermal plants in the Tongonan Geothermal field--the Tongonan, Malitbog and Upper Mahiao facilities. The upgrades will focus on the steamfield facilities that supply energy to all three plants.

Straddling Kananga and Ormoc in Leyte, the Tongonan geothermal field comprises 31 production wells and nine reinjection wells and spans more than 107,000 hectares of protected forest land.

International geothermal consulting firm Veizades & Associates, Inc. will plan the upgrades. This is the same professional geothermal engineering firm that developed The Geysers, the largest complex of geothermal energy facilities in the world.

Troyo said the firm has started collecting data, with final designs and cost estimates to follow. He added the design phase would take at least six months, followed by construction or equipment replacement over two to three years.

EDC is also exploring new technologies such as electrical submersible pumps to revitalise older wells and modular binary plants that don’t require extensive steam piping.

“These are still in the planning stage, but since they are already used abroad, we hope to replicate similar success,” Troyo said, citing the potential to add 10 megawatts (MW) to 15 MW without heavy infrastructure costs.

Turbines and generator rotors in Tongonan’s facilities have been replaced, and operations are now nearly fully automated. “Operations now focus on optimising and monitoring the plant, with less manual adjustment,” Troyo said.

Plans are also underway to replace nine cooling towers with new units that are resilient to typhoons and earthquakes.

With these upgrades, EDC expects Tongonan to remain operational until at least 2046.

Meanwhile, the firm’s other geothermal facilities are also due for rehabilitation and upgrades over the near term.  The 180 MW Mahanagdong facilities will undergo rehabilitation and capacity upgrades in three to five years, whilst Upper Mahiao is slated for complete plant replacement to boost generating capacity from 130 MW to at least 200 MW, supported by additional geothermal wells.

Aside from Tongonan, EDC owns seven other geothermal power stations operating across the Philippines, bringing total generating capacity to over 1,100 MW.