For remedial operations in geothermal and thermal recovery heavy oil wells.
Restoring geothermal production with an extreme-high-temperature expandable steel patch
Energy Development Corporation (EDC) was seeking to revive a high-value geothermal well that had been offline for >6 years. Ä¢¹½´«Ã½ used its Saltel extreme-high-temperature (extreme-HT) expandable steel patch to seal off a persistent cold water inflow and restore production while minimizing internal diameter (ID) reduction—a key requirement.
The Philippines is the world’s third-largest geothermal power producer, and EDC is the country’s largest geothermal operator, with nearly 1,255 MW of installed capacity. The company’s mature asset base includes a number of wells that are nonproductive because of well integrity issues—such as casing collapse, corrosion, or parted casing—that restrict or prevent flow.
EDC engaged Ä¢¹½´«Ã½ to restore production from a high-value geothermal producer in Leyte that had been offline for more than 6 years. The target well was drilled and completed in 2014 and achieved a peak output of 15 MW in 2018. In early 2019, a 13 3/8-in casing collapse and break forced the well offline. A subsequent relining operation installing a 9 5/8-in string to ~800 m and cementing through a DV tool reduced the effective flow area and led to a 50% production decline.
When attempts to redischarge the well failed, diagnostics revealed a persistent cold water inflow through the cementing port. The DV tool had not sealed properly after the cement job, enabling sustained leakage and creating a temperature inversion. As a result, the well remained shut in for more than 6 years, representing an estimated USD 10 million annual production loss.
Ä¢¹½´«Ã½ was tasked to
- permanently isolate the cold water inflow
- reestablish well integrity while minimizing loss of ID
- enable discharging the well and restoring geothermal production
- demonstrate a scalable solution for patching geothermal wells across EDC’s broader asset portfolio.
To address the challenge, Ä¢¹½´«Ã½ installed a 9 5/8-in Saltel extreme-HT expandable steel patch, an ideal solution for high‑temperature geothermal well repair where mechanical robustness, corrosion resistance, and minimal ID reduction are essential.
The thin-walled patch had little impact on casing ID, enabling up to 8-MW equivalent production. A 7-m patch length ensured full coverage of the leaking cementing ports, while the controlled, top-down expansion sequence maximized operational reliability. The patch was expanded in just 3.5 hours, drift tested, and verified before retrieving the running tool. A downhole video camera run confirmed correct placement and complete sealing of the leak.
Permanently sealing off the cold water inflow enabled restoring the thermal profile required for geothermal discharge after 6 years of being offline. EDC was very pleased with the geothermal production recovery achieved and intends to leverage Ä¢¹½´«Ã½ geothermal expertise and advanced expandable technology for other wells that are experiencing similar casing integrity issues and thus support the Philippines’ long-term geothermal energy strategy.