Bogowonto Begins Rail-Sector B40 Trial, Generator Target Set at 1,200 Hours

Yogyakarta — Indonesia's Ministry of Energy and Mineral Resources (ESDM) and state railway company KAI began a B40 trial in the rail sector on 22 July 2024. The blend of diesel fuel and 40% biodiesel is being tested in the generator set aboard the Bogowonto train, which operates between Lempuyangan station in Yogyakarta and Pasar Senen in Jakarta. The planned endurance test is 1,200 hours. The launch was not an announcement that the test had been completed or passed.

ESDM's director general for new, renewable energy and energy conservation, Eniya Listiani Dewi, described the event at Lempuyangan as the start of the railway-sector B40 trial. Both ANTARA and CNN Indonesia reported on the 22 July launch. It was a first for the rail sector, not the first B40 trial anywhere: Eniya said testing in the automotive sector had taken place earlier.

What the Bogowonto generator trial measures

According to Eniya's account reported by CNN Indonesia, the limited performance trial is intended to test the Bogowonto generator set's endurance over 1,200 hours. A return journey between Lempuyangan and Pasar Senen was estimated to take about 22 hours. She estimated around 50 return trips, or roughly two months, would be needed for the trial. Those figures were planning estimates at launch, not a record of hours or trips already completed.

ANTARA likewise reported the 1,200-hour minimum and the approximate 22-hour return journey. Neither report provides final technical results, measured changes in fuel consumption after the trial, or evidence that B40 has been approved for every train. The announced test concerns the train's generator set; it should not be presented as a completed fleet-wide assessment.

December results were an expectation, not a finding

Eniya said the trial would continue and its results were expected in December 2024. CNN Indonesia also reported her hope that technical guidance could be ready by the end of the year, ahead of possible B40 implementation in 2025. As of the 22 July reporting, these were prospective milestones. The two reports do not establish that the planned December findings existed or that a general rollout had been approved.

KAI vice president of logistics Suryawan Putra Hia backed the trial and, according to CNN Indonesia, said the railway used about 300 million litres of fuel annually, all of it then using B35. He said KAI was providing equipment for testing, including a generator set and locomotive. ANTARA reported his call for longer-term support to assess B40's effects on train engines. His optimism about a limited impact on engines was a view expressed before the trial's results, not an established performance finding.

Other sector tests were on the agenda

Eniya said testing in 2024 covered agricultural machinery and railways after earlier automotive work. Mining equipment, ships and power generation were among the further sectors she identified. CNN Indonesia reported plans for additional launches, including in East Kalimantan. Plans for tests in those sectors should not be confused with completed evaluations.

ESDM linked wider B40 use to reducing reliance on imported diesel and pursuing lower transport emissions. Those aims do not by themselves demonstrate a quantified benefit for rail operations. The Bogowonto trial was a step towards gathering evidence, with the evaluation still pending at the time. Readers can consult the biodiesel mandate data for broader blend-policy context.