Indonesia is expanding its biofuel program with ongoing trials of B50 fuel in its railway sector, building on earlier adoption of B40 biodiesel across its locomotive and generator fleet. The move reflects the nation’s commitment to renewable energy and its ambitious net-zero emissions target.
The Ministry of Energy and Mineral Resources initiated testing of B50 fuel in train diesel engines, including trials at the Lempuyangan Railway Supervisory Unit in Yogyakarta, according to reports from April 27, 2026. These tests involve evaluating generators running for 2,400 hours and locomotives on the Surabaya–Jakarta route over a six-month period.
“The railway sector is undergoing two tests… As you can see, the generators will run for 2,400 hours,” said Eniya Alistiani Dewi at the Lempuyangan PUK in Yogyakarta on Monday. The final phase of B50 testing for railways is scheduled for October 2026, with the goal of assessing real-world performance.
The B50 program, a blend of 50% diesel fuel and 50% biodiesel, has been under development for 15 years and is unique to Indonesia, which currently leads the world in its implementation. Road tests began on December 9, 2025, following laboratory assessments, and have since included the automotive, mining, agricultural equipment, shipping, and generator sectors.
State-owned railway company PT Kereta Api Indonesia (KAI) has already adopted B40 biodiesel for all its locomotives and generators, demonstrating its support for the Ministry of Energy and Mineral Resources’ renewable energy initiative. “All locomotives and generators operated by KAI use renewable energy through B40 biodiesel,” KAI Vice President of Corporate Communications Anne Purba said on Sunday, April 13, 2026.
The adoption of B40 is intended to lower emissions and position railways as a more environmentally friendly logistics and transportation solution. KAI is preparing to transition to B50, emphasizing safety through a series of technical trials before full deployment. The government’s broader strategy aims for national energy independence and achieving net-zero emissions by 2060.
Experts suggest that biodiesel and bioethanol could serve as transitional fuels as the transportation sector moves towards electric vehicles. The success of these biofuel initiatives will likely depend on consistent supply, as highlighted in recent industry analysis.
