Guwahati's older vehicles bear the burden of India's fast fuel transition as E20 becomes standard
India's transition to E20 petrol was hailed as a landmark achievement in the country's journey towards energy security and cleaner transportation. The shift happened much faster than originally planned.
While the initial roadmap had envisaged nationwide adoption by 2030, India achieved the target in 2025, five years ahead of schedule. The transition itself was equally swift. The country moved from E10 to E20 in just three years, compared to the nearly eight-year timeline originally envisioned under the National Biofuel Policy.
ALSO READ: Summer Workshops Offer Children a Break from Screens and a Chance to Explore
Today, E20 petrol, consisting of 20% ethanol and 80% petrol. It is the standard fuel available at petrol pumps across the country.
The policy has been projected as a win for the nation. India imports nearly 88% of its crude oil requirements, making it the world's third-largest energy consumer. Increasing ethanol blending reduces dependence on imported fossil fuels, supports domestic sugarcane farmers, saves foreign exchange, and lowers carbon emissions.
On paper, the policy appears to be a success.
But away from government presentations and policy announcements, many vehicle owners in Guwahati are asking a different question: Who really benefited from the rapid transition?
For thousands of motorists driving older motorcycles and cars, especially vehicles manufactured before E20 compatibility became common, the shift has come with unexpected costs. From reduced mileage and engine misfiring to carburettor failures and repeated workshop visits, many owners claim their vehicles have started behaving differently since E20 became the standard fuel.
At a local workshop in Guwahati, mechanics say complaints have increased significantly over the past few months.
Speaking to GPlus, one two-wheeler owner said his motorcycle began developing carburettor problems soon after E20 fuel became common.
"There are starting issues now. The bike doesn't run smoothly at low speed, and I have to keep accelerating just to prevent it from stalling. I recently had to replace the carburettor. The mileage has also dropped."
Another rider echoed the same experience.
"My bike broke down. When I took it to the mechanic, he said the carburettor had to be replaced with one compatible with E20 fuel."
Inside the workshop, mechanics say these are no longer isolated cases.
According to one experienced mechanic, nearly 15 to 20 motorcycles arrive every day with similar complaints.
"Whether it's a carburettor bike or a fuel-injected motorcycle, many are facing missing, stalling and starting issues. If replacement carburettors are available, we replace them. But for many older models, parts are difficult to find. In those cases, owners have no option but to continue using the vehicle despite the problem."
He added that the majority of complaints involve engine misfiring, difficulty starting the engine and stalling at slow speeds.
"The vehicles perform relatively normally at higher RPMs. But as soon as the speed drops, the engine begins to misfire. We started seeing these complaints after E20 was introduced, especially in vehicles manufactured before 2023."
For many commuters, the concern isn't just engine performance but also fuel efficiency.
A car owner said his vehicle earlier delivered between 20 and 25 kilometres per litre.
"Now in city traffic it barely gives around 16 kilometres. Sometimes it even drops to 12 or 13. Even the engine sounds different now."
Such complaints are not uncommon.
Experts explain that ethanol contains lower energy than conventional petrol. Since ethanol has a lower calorific value, the engine requires more fuel to produce the same amount of energy, which can result in a reduction in mileage.
Depending on vehicle design, engine condition and driving habits, mileage losses of around five to ten percent are possible, particularly in vehicles that were never designed for higher ethanol blends.
For daily commuters already struggling with rising fuel prices, even a small drop in mileage translates into higher monthly fuel expenses.
The primary challenge lies in compatibility.
Most newer vehicles manufactured after automobile companies began preparing for E20 are designed with ethanol-resistant materials and modified fuel systems.
However, older vehicles particularly those certified only for E10 fuel were never engineered to operate continuously on E20.
Ethanol is hygroscopic, meaning it absorbs moisture from the atmosphere more readily than petrol. Excess moisture can increase the risk of corrosion in metallic components over time if the fuel system is not designed for higher ethanol content.
Mechanics say they have observed rust formation inside fuel tanks in several older motorcycles.
"Water seems to accumulate because of the ethanol blend. We have seen rust forming inside fuel tanks," one mechanic told GPlus.
In addition to corrosion, ethanol can gradually degrade rubber seals, plastic components, hoses and other fuel-system parts that were originally designed only for lower ethanol blends.
These problems are particularly common in older carburettor-equipped motorcycles.
For many riders, the issue extends beyond repair bills.
One motorcycle owner described how his bike now shuts down unexpectedly while in motion.
"For the last month my bike suddenly switches off on the road. It starts misfiring and refuses to restart. It becomes a huge problem during traffic jams."
Expressing his frustration, he questioned why consumers have no alternative fuel choice.
"If we are paying the full price for fuel, we should get pure petrol. We deserve the original product."
Another senior driver, with more than two decades of driving experience, said he had never encountered such problems before.
"I have been driving for 25 or 26 years, and I have never faced anything like this. What we are seeing now has become a major problem."
Perhaps the biggest concern among owners of older vehicles is the absence of an alternative.
Since E20 has become the standard petrol variant across the country, motorists whose vehicles are incompatible have little option but to continue filling E20. Replacing vehicles is financially unrealistic for most families. Upgrading carburettors, changing fuel-system components or repeatedly repairing ageing vehicles also adds to the cost of ownership.
Many vehicle owners say the rapid pace of implementation left them with little time to prepare.
The Centre has consistently defended the ethanol blending programme as a strategic national policy.
India imports nearly 88 percent of its crude oil requirement. Reducing dependence on imported fuel remains one of the key objectives behind ethanol blending. By increasing domestic ethanol production, the government aims to reduce foreign exchange expenditure on oil imports while simultaneously creating additional income opportunities for farmers, particularly sugarcane growers.
Environmental considerations also form a major part of the policy. E20 fuel produces lower net carbon emissions compared to conventional petrol, making it a cleaner transportation fuel and contributing towards India's climate commitments.
Government studies have also stated that E20-compatible vehicles are capable of operating safely on the blended fuel without significant performance issues.
Petrol pump operators, however, maintain that E20 itself is not responsible for the complaints.
A petrol pump executive in Guwahati dismissed concerns regarding mileage reduction.
"There is no difference in engine performance or mileage because of E20. Mileage remains the same."
He said much of the public concern stems from misconceptions surrounding ethanol.
"People have developed a fear that E20 turns into water, but that isn't true."
However, he acknowledged that certain older vehicles not designed for E20 could face minor issues.
"There may be slight problems for vehicles that are not E20-compliant, but otherwise the fuel does not create any negative impact."
He further claimed that the petrol pump had not received formal complaints from customers regarding older vehicles.
"Most of what we hear are rumours rather than actual complaints."
The contrasting claims highlight the complexity surrounding India's ethanol programme.
On one hand are national objectives, reducing crude oil imports, cutting emissions and strengthening energy security.
On the other are motorists who believe their older vehicles have become unintended casualties of a policy implemented at unprecedented speed.
Whether every complaint can be directly attributed to E20 remains a subject of debate. Vehicle age, maintenance practices, fuel quality, weather conditions and existing mechanical problems can also influence performance.
Yet the consistency of complaints emerging from riders, mechanics and drivers suggests that concerns surrounding older vehicles cannot be dismissed outright.
As India races towards cleaner fuels and greater energy independence, Guwahati's roads present a reminder that large-scale policy shifts often have consequences beyond official targets.
For thousands of owners still driving pre-E20 vehicles, the transition has not merely changed what goes into their fuel tanks, it has changed the cost, reliability and everyday experience of keeping their vehicles on the road.
The larger question, therefore, is no longer whether India successfully implemented E20.
It already has.
The question now is whether the country's older vehicles and the people who still depend on them every day were given enough time and support to make that journey with it.