Jakarta. Indonesia’s planned rollout of a 50% biodiesel blend for vehicles and industrial use is expected to become the first program of its kind in the world and is already drawing interest from other countries seeking to study and replicate the model, a senior Energy Ministry official said.

The initiative, known as B50, is scheduled to be implemented on July 1 and is currently undergoing road trials using diesel-powered vehicles. Testing has now entered a new phase involving diesel rail operations.

Eniya Listiyani Dewi, director general of renewable energy with the ministry, said Indonesia began developing biodiesel blending programs around 15 years ago and is now successfully using a 40% biodiesel mix without major issues.

She said the next step toward a 50% blend is the result of years of research and development.

“There are no technical references we can access. We are moving forward without an example to follow, and that is something we are proud of,” Eniya said.

“Many countries are now coming to us and making contact to learn how to develop B50, because there is no other reference besides Indonesia,” she added, without naming the countries involved.

Testing in the railway sector will begin with diesel generators serving the Yogyakarta–Jakarta route, followed by trials using diesel locomotives.

The rail generator trial will run for 2,400 operating hours.

After that, locomotive testing will be conducted on the Surabaya–Jakarta route over six months.

“The final phase of B50 railway testing is expected in October 2026. We are conducting trials under real operating conditions so we can see the actual results,” Eniya said.

She added that a broader series of B50 trials on engines and vehicles began in December last year, following extensive laboratory testing.

“Since Dec. 9, we have launched the full trial program covering automotive use, mining equipment, agricultural machinery, shipping, generators, and now railways,” she said.

Railway testing had been delayed while authorities waited for the end of the annual Eid al-Fitr passenger travel surge in late March.

Heru Kuswanto, infrastructure management director at state-owned railway operator KAI, said the company fully supports the B50 trial and is working with the Energy Ministry to evaluate locomotive engines and generator performance while using the new fuel blend.

“The most important priorities are safety, security, and continuous technical evaluation to maintain the reliability of railway assets. We hope the program runs smoothly and delivers optimal benefits for the railway industry while supporting the national energy transition and sustainable, environmentally friendly transportation,” Heru said.