Should we welcome ethanol ?

Using ethanol in vehicles offers a mix of strategic national benefits and practical challenges for consumers. While it can strengthen a country's energy independence and support agriculture, it often leads to reduced fuel economy and potential issues for older vehicles.

Here is a breakdown of the key pros and cons of using ethanol-blended fuel in vehicles.

Reduces crude oil imports and saves foreign exchange.
Supports farmers by creating a new market for agricultural produce like sugarcane and maize.

Can divert crops from food to fuel, potentially impacting food security and prices.
Production of feedstock like sugarcane is highly water-intensive, straining water resources.

Environmental
Lowers lifecycle greenhouse gas emissions compared to petrol; some studies show a 50-65% reduction.

Can lead to reduced tailpipe pollutants like carbon monoxide.

Environmental benefits must be weighed against the heavy resource use (water, fertilizer) for growing crops.

Large-scale production can lead to soil degradation and monoculture farming.

Vehicle Performance & Cost
Higher octane rating can improve engine performance and acceleration when vehicles are properly tuned.

Potential for lower fuel cost per litre compared to petrol.

Significantly lower energy density (about 30% less than petrol), leading to reduced fuel efficiency (mileage) .

Corrosive to rubber and metal parts, potentially damaging fuel lines, seals, and gaskets in non-compliant vehicles.

Infrastructure & Technology
Allows for the use of flex-fuel vehicles (FFVs) that can run on various ethanol blends.
Requires dedicated, compatible vehicles; older cars may need costly retrofitting or are not compatible.

Limited refuelling infrastructure for high-ethanol blends like E85 and E100 is a major barrier.

For the average driver, the lower energy content of ethanol is the most noticeable downside. It means you'll need to fill up more often to travel the same distance. One real-world test showed a motorcycle's fuel efficiency dropped by nearly 43% when switching from E20 to E85. This means that even if ethanol is cheaper per litre, it can end up being more expensive per kilometre driven.

Furthermore, ethanol's corrosive nature can be problematic. It can damage fuel system components like rubber seals and gaskets, especially in older vehicles that weren't designed for it. In India, many vehicle owners have reported reduced mileage and increased maintenance costs after the rollout of E20 fuel.

National and Environmental Strategy
From a national perspective, ethanol offers a powerful way to increase energy security. By producing fuel domestically, countries can reduce their vulnerability to volatile global oil prices and geopolitical shocks. For example, India's ethanol blending program has saved billions in foreign exchange by substituting millions of tonnes of crude oil imports.

However, this strategy has its own trade-offs. The heavy reliance on water-intensive crops like sugarcane for ethanol production can exacerbate water scarcity. There are also significant concerns about using food crops (like maize and rice) for fuel, which can affect food availability and prices—a dilemma often framed as "food versus fuel".

A Bridge to the Future?
Because vehicles that can use high-ethanol blends often require specific, corrosion-resistant materials and sensors, the infrastructure and vehicle availability are currently very limited. This creates a "chicken-and-egg" problem: consumers won't buy flex-fuel vehicles if fuel is hard to find, and companies are hesitant to build stations without enough cars.

Ultimately, ethanol is seen by many experts not as a final solution but as a "bridge fuel" —a way to reduce emissions and oil dependence in the near term while the world transitions to electric vehicles and other technologies.

By Jamuna Rangachari