State power utility PT PLN has been working on a combination of renewable energy expansion, advanced carbon capture technologies, and modernized energy infrastructure to ensure sustainable and reliable electricity supply for the nation in support of the country’s Net Zero Emissions (NZE) target by 2060.
To address decarbonization, PLN is exploring the integration of Carbon Capture and Storage (CCS)/Carbon Capture Utilization, and Storage (CCUS) technologies into coal-fired power plants (PLTU).
While CCS/CCUS implementation is costly, PLN considers it a necessary measure to manage emissions from critical power plants.
Coal-fired plants currently account for a significant portion of Indonesia’s energy generation, and abruptly replacing them is deemed unfeasible due to time and infrastructure constraints.
Instead, PLN plans to retrofit existing PLTU (Coal-fired power plants) with CCS/CCUS technology, significantly reducing emissions without compromising energy reliability.
“We will not have enough time (for immediate production), if we turn all the PLTUs off and simultaneously replace them. So the solution is indeed we select which ones that we install with the CCUS technology. This is a choice that must be made,” Chairani Rachmatullah, President Director at PT PLN Enjiniring, an engineering consultancy subholding of PLN, said on Saturday, January 18, 2025.
The company’s Accelerated Renewable Energy Development (ARED) program outlines a gradual shift towards renewable energy sources, including solar, wind, hydropower, and geothermal.
While renewable energy will dominate the energy mix, a small portion of coal-fired plants will remain operational, equipped with high-tech CCS/CCUS systems.
Renewable energy challenges
Renewable energy sources like solar and wind are inherently variable, thus called Variable Renewable Energy (VRE) with fluctuations in power generation due to weather conditions.
“Why variable because sometimes renewable energy variables are wind and sun,” she said.
To overcome this, PLN is developing strategies for flexible generation, allowing power plants to adapt to changing energy demands.
“The sun has (there are) clouds, its MW (Megawatt) decreases, if the wind stops there is no electricity. So, there must be intermittency technology,” she said further.
This includes upgrading PLTU to operate more efficiently under varying conditions and integrating energy storage systems, such as batteries to stabilize the grid during periods of low renewable energy output.
Role of green energy super grid
PLN is also focused on building a green energy super grid, a nationwide transmission network connecting regions with abundant renewable energy potential − such as Sumatra, Kalimantan, and Nusa Tenggara − with high-demand areas like Java and Bali.
“So, the challenge in electricity is how to operate between the PLTU, the VRE Generator, and then finally we entered the option of expanding transmission. PLN introduced it as a green energy super grid,” she said.
Currently, resource-rich regions face challenges due to limited local demand and inadequate transmission infrastructure. The super grid will enable the full utilization of Indonesia’s vast renewable energy potential.
“So in ARED, 75 percent renewable energy, with nuclear and battery as a storage system. So this battery will balance the PLTU that uses CCS. This CCS PLTU should not be too much, so we install batteries in PLTS turbines, while electricity from the sun is sent to the battery. We store the battery when there are clouds and when the wind is not strong. The battery can go in (replace),” she explained.
Long-term vision
PLN’s roadmap includes CCS/CCUS as a long-term solution, with initial implementation targeted for 2040.
The company is also exploring Indonesia’s vast saline aquifers as potential CO2 storage sites.
These underground reservoirs offer a promising opportunity to store captured emissions, supported by Indonesia’s geological advantages.
Natural gas will also play a transitional role, accounting for a portion of the energy mix by 2060.
Gas power plants provide reliable energy and help address intermittency issues associated with renewable sources.
PLN acknowledges that achieving NZE 2060 requires a combination of technological innovation, economic feasibility, and supportive policies.
The company is optimistic that advancements in CCS/CCUS technology and renewable energy will make these solutions more affordable over time.
