Ukudu power plant under repair

By Pacific Island Times News Staff

The Ukudu Power Plant continues to operate at reduced capacity while several generating units require either scheduled maintenance or repairs, necessitating

load shedding, the Guam Power Authority said.

"The combination of Ukudu’s reduced output, scheduled maintenance and unexpected unit repairs has tightened generation reserves in recent weeks," GPA said.

The 198MW-combined-cycle Ukudu Power Plant, which was switched on in December 2025 and touted to stabilize Guam's power capacity, is currently generating approximately 90MW to the grid.

GPA said the plant's three combustion turbines are currently offline for repairs.

GPA acknowledged that the recent load shedding and extended steam turbine outage have also raised questions about Ukudu’s long-term reliability.

Guam Ukudu Power, the independent power producer that owns and operates the plant, anticipates returning the steam turbine to service by the end of August.

Upon the commissioning of Ukudu, GPA was required to permanently shut down two of its power plants in Cabras, resulting in a loss of 50MW of capacity.

GPA said it is working to restore unavailable capacity by completing maintenance and overhauls on generating units that had been deferred during the previous capacity shortage, thereby keeping those units available. 

This work was scheduled after Ukudu added capacity to the system.

To mitigate the current generation shortfall, GPA said it is working  to return

unavailable units to service as quickly as practicable, adjusting maintenance

schedules where possible, maximizing available generation across the system, and closely monitoring peak demand and reserve capacity.

At 5:47 a.m. on Aug. 18 available generation capacity  decreased from 259 MW to approximately 216 MW while emergency repairs were performed on Piti

Unit 8, GPA said.

While the repair was targeted to be completed by 5 p.m., the unit experienced an additional issue and didn’t return to service until around 9 p.m. Wednesday. last night, which subsequently ended load shedding.

GUP initially took the steam turbine offline on June 23 to address operating issues, with a planned return to service by July 8. 

Upon completion of the repairs, they identified issues with the steam turbine turning gear spring supports that also required replacement. 

Because these parts are special-order components, the steam turbine outage has been extended to approximately Aug. 28.

“The issues identified during the plant’s early operating period are not out of the ordinary, but they must be corrected now to support reliable performance over its operating life," GPA General Manager John M. Benavente said.

“We understand why customers have questions when a new plant experiences extended repairs; some adjustments and repairs during the early operation of

 a new generating facility are expected, but that does not lessen the importance of addressing them. The priority is to identify and correct these issues now so Ukudu performs reliably over the long term, particularly because the plant will ultimately be transferred to the people of Guam under the 25-year Build-Operate-Transfer agreement.” Benavente added.

GPA continues to monitor Ukudu’s output, efficiency and overall  performance

 to ensure the plant performs as required under the Energy Conversion Agreement.

GPA said load shedding remains a last resort and is implemented only when customer demand exceeds available generation.

GPA advised customers to help reduce pressure on the system by conserving electricity during the evening peak period, particularly between 5 p.m. and 11 p.m., while generation reserves remain constrained.