HAGÅTÑA (The Guam Daily Post) — After spending a bit of time offline due to generator issues, Cabras 2, one of Guam’s baseload generation units, managed to return to service Wednesday morning, only to trip offline again because of a possible boiler tube leak. The Guam Power Authority and its performance management contract partner, Taiwan Electrical and Mechanical Engineering Services Inc., are evaluating the unit to provide resources to improve the reliability of the boiler, GPA said.
There is some good news for the island’s generation system, as the Macheche Combustion Turbine Unit returned to service Thursday after the completion of emergency repairs. But another combustion turbine, Dededo CT Unit 1, continues to undergo repairs and GPA anticipated that it would return to service Thursday or Friday.
Guam has been under ongoing notices for rotating power outages as generators are taken offline now and again, reducing the amount of electricity available to meet customer demand. The outages are used to maintain grid stability when demand exceeds capacity.
A major combustion turbine, Yigo CT, remains offline for repairs to damage sustained during Typhoon Mawar.
Baseload units serve as the main generators for the island, but these are now older units.
The Cabras 1 and 2 units are nearly a half-century old, while another pair of baseload units, Piti 8 and 9, are about 24 years old.
“Emergency repairs are sometimes needed and the units have to be taken offline in a moment’s notice to avoid further damage to the machines. Repair work to baseload units are extensive and complex, the unit must cool sufficiently to allow safe entry by generation personnel before repair work can begin,” GPA stated in an update issued Thursday on the power system.
At the same time, non-baseload units, such as the combustion turbines, have been running longer hours than usual, GPA said.
“These units have only been on an abbreviated preventive maintenance schedule to assist with generation shortfalls. These non-baseload generation units need their required preventive maintenance hours in order for the units to run reliably,” GPA stated in its update.
A new power plant in Ukudu is supposed to serve as the next main generation facility for Guam, leading to the retirement of the aged Cabras units. But damage from Typhoon Mawar has delayed the plant’s completion.
Peak demand times take place in the evening, and GPA has been issuing outage schedules, which can be found on the utility’s Facebook page, so residents can prepare in case the outages are needed.
Solar power plants contribute to energy production during the day, earlier than when demand peaks in the evening. Solar power also is dependent on the weather.
Customers are encouraged to conserve power between 5 p.m. and 11 p.m.
GPA also has engaged with large power customers and the U.S. Navy to participate in an interruptible load program in which these customers use their own generators to help shave off demand during peak demand times.
The Cabras Power Plant is seen Sunday, Aug. 20, 2023, on Cabras Island.
