PLN's biomass unit pushes fuel standards to scale coal-plant co-firing nationwide

What happened

PT PLN Energi Primer Indonesia (PLN EPI), the fuel supply arm of state utility PLN, used a Material Handling Innovation for Wood-Based Industries symposium in late July to make a pointed argument: Indonesia's push to co-fire coal power plants with biomass no longer hinges mainly on how much agricultural and forestry residue the country can produce. It hinges on whether that residue can be collected, graded, and delivered to specification, at scale, on a schedule power plants can plan around.

Hokkop Situngkir, PLN EPI's Director of Biomass, told the symposium that the success of the co-firing program is determined by supply chain efficiency, fuel quality standardization, and reliable processing infrastructure, rather than by the underlying volume of biomass available nationally. It is a notable reframing. Indonesia's biomass resource base is large by any measure; Situngkir has separately cited a national potential of 83.4 million tons a year, concentrated in Sumatra (42.8 million tons) and Kalimantan (18.9 million tons). The binding constraint, in PLN EPI's own account, sits downstream of the raw resource, in logistics and quality control.

That framing matters because co-firing is one of the few decarbonization levers Indonesia can pull without idling existing coal assets. Roughly 90 percent of the country's installed generation capacity still runs on fossil fuel, spread across some 200 coal-fired units at 52 locations, another 200 gas and combined-cycle units, and close to 800 diesel units, according to figures Situngkir presented. Retiring that fleet outright is neither fast nor cheap. Blending biomass into the fuel mix lets plants cut their coal share and their emissions intensity while continuing to generate, which is why PLN EPI has made supply chain engineering, not just feedstock sourcing, the center of its 2026 strategy.

The numbers behind it

PLN EPI supplied 2.35 million tons of biomass to its co-firing fleet in 2025, which the company says avoided 2.72 million tons of carbon dioxide equivalent emissions over the year. Separate reporting on the program's implementation status put biomass utilization at 932,906 tons across the 52 participating plants as of June 2026, sourced from 16 distinct feedstock types with an average calorific value of 3,263 kilocalories per kilogram, indicators of the quality tracking now built into the program.

Cumulative supply across 2023 to 2026 stands at 4.77 million tons, dominated by two feedstock categories: sawdust at 54.6 percent and woodchips at 22.4 percent. PLN EPI's forward targets step up materially from here, to 3.65 million tons in 2026 and 4.07 million tons in 2027, with a longer-range ambition of reaching 10 million tons by 2030. Meeting the near-term targets alone would require roughly 9 million tons of biomass supply capacity feeding into the 52-plant, 18,154 megawatt co-firing fleet, a scale-up that explains why standardization, rather than headline feedstock potential, has become the company's stated priority.

To de-risk that scale-up for suppliers, PLN EPI has introduced purchase contract schemes running up to five years, giving farmers, cooperatives, and biomass processors the revenue certainty needed to invest in collection and processing infrastructure rather than selling into a spot market. The company frames this explicitly as ecosystem-building rather than simple procurement.

"Bioenergi bukan hanya mengganti batu bara. Yang kami bangun adalah ekosistem bioenergi dari desa hingga pembangkit listrik," Situngkir said, describing the program as bioenergy that does more than substitute for coal, built as an ecosystem stretching from villages to power plants.

Feedstock sources named by PLN EPI include palm empty fruit bunches, palm shells, rice husks, corn cobs, palm fronds, and wood waste, all residues drawn from forestry, plantation, and agricultural operations rather than purpose-grown biomass, a distinction the company has emphasized to preempt land-use and deforestation concerns.

Why it matters

Indonesia's energy transition debate tends to center on new-build renewables, solar, wind, and storage, where the country still trails regional peers on installed capacity. Co-firing is a different kind of lever: it improves the emissions profile of assets that already exist and are already paid for, without waiting on new transmission or permitting cycles. For an economy where coal still anchors around 90 percent of generation, that makes co-firing one of the more immediately deployable decarbonization tools available to policymakers and to PLN itself.

The standardization push also has a regional development dimension that is easy to overlook in aggregate emissions figures. PLN EPI has been building physical collection infrastructure to match its sourcing ambitions, including biomass hub facilities in Tasikmalaya and Ciamis in West Java designed to aggregate and pre-process residue from surrounding farms before it reaches power plants. The company's broader biomass ecosystem plan, tied to a 2025 to 2029 new-and-renewable-energy target of 12.22 gigawatts, projects roughly Rp 1.682 trillion in associated investment and around 760,000 green jobs across the supply chain, from smallholder collection through processing and logistics.

That employment and investment case is precisely why PLN EPI has chosen to lead its public messaging with supply chain quality rather than with tonnage targets alone. A biomass program that cannot guarantee consistent fuel specification to power plant operators will struggle to hold its purchase contracts, however generous the residue potential looks on a map. Standardization is what converts a resource estimate into a bankable, repeatable industrial input.

What comes next

The next test for the program is execution against its own numbers: whether 2026 supply reaches the stated 3.65 million ton target, whether the five-year purchase contracts attract enough farmer and cooperative participation to build durable collection networks, and whether the Tasikmalaya and Ciamis hub model is replicated at the pace needed to support 52 plants simultaneously. PLN EPI has signaled it intends to keep expanding hub infrastructure through the remainder of the decade as co-firing volumes climb toward the 10 million ton mark targeted for 2030.

Sirkularium's view

For government and public institutions, the PLN EPI case is a useful illustration of a broader principle in Indonesia's circular economy transition: resource abundance and program success are not the same thing. The country's biomass potential is not in question. What has determined whether that potential converts into avoided emissions is quality standardization, contract structures that give suppliers planning certainty, and logistics infrastructure built ahead of demand rather than in response to it.

Institutions overseeing co-firing policy, industrial decarbonization roadmaps, or regional biomass economic development programs should treat supply chain standards, not just feedstock inventories, as the metric worth tracking closely. Standardized fuel quality specifications, transparent calorific value reporting, and multi-year offtake certainty are replicable across other biomass value chains beyond power generation, including industrial boilers and cement kiln co-processing, sectors also named in Indonesia's industrial decarbonization roadmap. Financing and technical assistance aimed at collection and pre-processing infrastructure, rather than at plantation-level supply alone, is likely to have the largest marginal effect on how quickly national co-firing targets are met.