Indonesian state railway company, PT Kereta Api Indonesia (KAI), has begun testing the use of a 50% biodiesel blend (B50) in its train operations. This initiative is part of a broader effort to accelerate the country’s energy transition and bolster renewable energy programs. The trial aims to assess the feasibility and impact of B50 on train performance and infrastructure. KAI’s move aligns with national goals to reduce reliance on fossil fuels and lower carbon emissions within the transportation sector. Further testing will determine the potential for wider implementation across the railway network. The company anticipates this transition will contribute significantly to Indonesia’s sustainability objectives. This pilot program represents a concrete step towards greener railway operations in Indonesia.