Green Fuel

Ethanol, a fuel that emits 44%–52% less greenhouse gas than petrol, is presented as a viable step towards sustainability for India, a major sugar producer like Brazil. By adopting flex-fuel technology and ethanol production techniques, India could significantly reduce CO2 emissions without immediate radical changes to its energy infrastructure.

This article was first published in The Mint. You can read the original at this link.

In an earlier article in this column, I had pointed out that plants were the solar cells of the natural world:

Plants use photons from sunlight as sources of energy to create chemical bonds between molecules of carbon dioxide and water. This process, called photosynthesis, is how they create carbon-based stores of energy that they use to grow. When we burn plant matter, this energy gets released in the form of light and heat energy. Plants are, therefore, the batteries of the natural world, capturing energy from the sun and storing it in a stable form that can be transported from place to place and burnt to release the energy trapped within. When humans harnessed fire, they learned to generate energy at will. This was a turning point in our evolution, and arguably the one scientific discovery to which every subsequent technological advancement of the species can be traced. It would not be an exaggeration to say that it was our ability to harness fire that set us firmly and irreversibly on the path to civilisation.

The problem is that these fuel sources take millennia to produce and, once consumed, are lost forever. They emit greenhouse gases that have warmed up the planet to the point where the technology that once contributed to our civilisational advancement has become an existential threat to us all.

Regular readers of this column will know that I am bullish on electric vehicles (EVs). I have written at length on the advantages of battery-swapping technologies and the Vehicle-to-Grid opportunities they present. However, as much as EVs are themselves zero emission, as long as the batteries they use are charged using electricity from the grid, their net carbon impact is still high because of how many of our power plants use fossil fuel for generation.

Until we build a purely renewable energy grid, we will need to keep looking for less polluting energy sources. Fuel that can be replenished - harvested year after year rather than mined and consumed once and for all. That is environmentally friendly and emits less carbon into the atmosphere than is consumed in its creation.


I’d heard about ethanol fuel for a while but, for some reason, had assumed that it was still experimental technology. I thought that in order for it to work, we’d need a completely different internal combustion engine - one that had been re-engineered to be able to use ethanol.

It was only recently that I learned, to my surprise, that not only was this not true, a number of countries have, for a while now, been mixing ethanol into their petrol and using it in cars barely different from those on our streets. In 2003, ever since flex-fuel technology was first deployed in Brazil, car owners have had the option to fill their tanks with either petrol, a mixture of ethanol and petrol or 100% (hydrous) ethanol. Today, as many as 93% of the vehicles in Brazil are capable of running on ethanol.

Ethanol emits between 44%–52% less greenhouse gas emissions as compared to petrol. As a result, even when it is combined with petrol it significantly reduces the CO2 emissions of the vehicle. In the two decades since the deployment of Flex Fuel technology, Brazil’s contribution of CO2 equivalents into the atmosphere has been as much as 1.34 billion tons less than it could have been. This is largely why, despite being one of the most densely populated cities on the planet, Sao Paulo is among the least polluted.

Ethanol production in Brazil is highly efficient. Most facilities use residual waste from the process (bagasse) for power - generating enough to run the plant with excess to spare. In 2020 as much as 5% of the total power consumption of the country was met from bio-electricity generated from bagasse.

What’s In It for Us?

So why is all this relevant to India?

Brazilian ethanol is produced from sugarcane. As a result it has a much higher energy balance that corn-based ethanol that is produced by the United States. Even if they want to, very few other countries can produce sugar ethanol. One of the peculiarities of sugarcane is that once harvested, it needs to be converted into ethanol within 24 hours or else it spoils. As a result all sugar ethanol production plants have to be located right in the centre of the fields from which they get their raw materials.

What this means is that only those countries that cultivate sugarcane can produce ethanol from it. The real reason why Brazil is one of the world’s leading producers of sugar ethanol is because it also happens to be one of the world’s largest producers of sugarcane.

Which is what brings us to India.

Like Brazil, India is a major sugar producer. This year, with production estimated to touch 41 million metric tonnes, we will probably even be the world’s largest. This means that, like Brazil, India is one of the very few countries in the world that can quickly adapt its fuel supply to incorporate ethanol. All we need to do is adopt the production techniques that have been perfected in Brazil over the last 50 years and mandate that all internal combustion engine vehicles be redesigned to incorporate flex-fuel technology. If we can implement the changes, we will significantly reduce our CO2 emissions allowing us to make progress towards our COP26 commitments without the need for immediate radical alterations to our energy infrastructure.

An Easy First Step

Earlier this month, the Union Minister for Transport flagged off the country’s first flex fuel car that was capable of running on petrol, ethanol or any mixture of the two. He said that ethanol-blended fuel would likely be available in select parts of the country by next year with a nationwide rollout planned in a few years time.

To be clear, ethanol is not a complete solution to the climate challenges of the world. It is, however, an easy first step towards a more sustainable future - one that will buy us the time we need over the next decade or so, to substantively restructure our energy infrastructure in the way that needs to be made in order to effect lasting change.