India’s biofuel journey may soon move beyond petrol. After introducing E20 petrol across the country, the government is now preparing for the next step. Union Road Transport and Highways Minister Nitin Gadkari has said India is working towards allowing up to a 15 per cent blend of isobutanol in diesel by 2027.
The plan is part of the government’s effort to reduce crude oil imports while increasing the use of fuels made from agricultural sources. Pilot projects have already delivered encouraging results, giving confidence for wider use in the future.
Why is the government looking at isobutanol?
One of the biggest reasons is that ethanol cannot be mixed directly with diesel. To solve this problem, ethanol can be converted into isobutanol, which blends with diesel much more easily.
Gadkari said this fuel has already been tested successfully. According to him, two Kirloskar diesel generator sets have been operated on 100 per cent ethanol and isobutanol, showing that engines can work with these fuels.
What makes isobutanol different?
Isobutanol is considered a next-generation biofuel because it offers several benefits over conventional ethanol.
Some of its advantages include:
- Mixes properly with diesel
- Better energy density than ethanol
- Produces lower soot or particulate emissions
- Does not absorb moisture like ethanol
- Can reduce dependence on imported fossil fuels
- Can increase demand for biofuels produced in India
E20 backlash
The announcement comes only a few days after the government responded to criticism around the E20 petrol programme. The Ministry of Petroleum and Natural Gas defended the ethanol blending policy and said several claims being shared on social media were misleading.
Even as the E20 programme continues, work has already started on the next phase of India’s alternative fuel strategy.
There are challenges too
While isobutanol offers many benefits, experts also point out a few concerns.
- Production cost is currently higher than conventional diesel
- Higher blends may require engine recalibration
- Some operating conditions can increase NOx emissions
- Slight drop in fuel efficiency may be possible
- Long-term effects are still being studied
Experts believe blends of up to around 20 per cent are unlikely to cause major problems in most applications, although further testing will continue.
15% isobutanol blending plan at a glance
| Details | Information |
| Blend target | Up to 15% isobutanol in diesel |
| Expected rollout | 2027 |
| Source | Isobutanol produced from ethanol |
| Main benefit | Can blend with diesel unlike ethanol |
| Pilot testing | Successfully demonstrated on Kirloskar diesel generators |
| Key objective | Lower crude oil imports and support cleaner fuels |