Indonesian state-owned utility PLN is currently studying the possibility of early retirement of two Suralaya coal-fired power complex units, as part of the country's broader plans to reduce emissions.
The study is assessing the shutdown plan, which includes the cost and timeline for its implementation, PLN said. The company can then look for financiers for the plant's early retirement, PLN added.
The plant currently comprises eight units, with three 600MW units added in 1996 and 1997, and another 625MW unit added in 2011, taking total capacity to 4,025MW. But the original plant consisted of four 400MW units, with a total capacity of 1,600MW. It first started commercial operations with the first unit in 1984, and the second unit the year after. The third and fourth units came on line in 1988 and 1989,respectively.
The original four-unit coal plant was chosenfor the planbecause of its age, low efficiency, and relatively high emissions, PLN said. These four units currently consume roughly 2mn t/yr of coal, resulting in a total coal consumption of 8mn t/yr at a total capacity of 1,600MW. This compared with the 2,000MW Batang power plant, which uses ultra-supercritical technology, and consumes between 7.3mn-8mn t/yr of coal, PLN said.
PLN is also working on a gradual coal phase-down of all four units of the original power plant by derating its capacity. The company aims to reduce the power generation units' capacity to 85-90pc of its boilerplate rating starting this year, with plans to continue decreasing it over the course of the next 2-3 years to 75pc, bringing the output capacity of the four units to 300MW each for a total of 1,200MW.
This is expected to result in a 2mn t/yr decline in coal consumption if the derating target is met, PLN said.
Progress of the coal plant's phasedown will be dependent on the grid's demand and stability, PLN said.
The power plant is connected to the Java-Bali grid, the largest grid in Indonesia in terms of electricity demand, and is responsible for supplying electricity to Jakarta. Additional renewable energy sources must come on line to offset the loss in electricity supply resulting from the derating of the four units to the 75pc target, PLN said.
