Fact check: Does producing 1 litre of ethanol take 10,000 litres of water?

Industry says the 10,000-litre figure is a misread. It is, but that's not the whole story.

Hyderabad: A number has been doing the rounds – 10,790 litres, the amount of water needed to produce just one litre of ethanol from rice. The figure has since led to a sharp critique of India’s ethanol blending programme. The industry is fighting back, and the truth, as it turns out, is more complicated than it looks.

The Grain Ethanol Manufacturers Association (GEMA) called the 10,000-litre figure “factually misleading and devoid of context,” saying it refers to the total lifecycle water footprint of the crop, including rainfall absorbed during cultivation, and not what ethanol plants actually consume. 

GEMA says modern distilleries use only three to five litres of process water per litre of ethanol.

On this specific point, GEMA is correct. 

The 10,000-litre number, shared by Food Secretary Sanjeev Chopra at a global conference in Delhi last year, is drawn from virtual water accounting – a methodology that adds up all water a crop absorbs across its growing cycle, including rainwater that would have fallen on that land. It is a tool for understanding agricultural water stress, not industrial water consumption. 

Conflating the two is a methodological error, and critics of ethanol production have gone all guns blazing on it without the caveat. 

However, the industry’s rebuttal skips over a few things.

Where the rebuttal falls short

The more serious concern is not how much water a distillery draws from a pipe, but what grows in the fields feeding it. India’s ethanol programme runs primarily on sugarcane and, increasingly, rice. These two are the most irrigation-heavy crops in the country. 

Growing one kilogram of rice requires an estimated 3,000 to 5,000 litres of water, the bulk of which is drawn from groundwater, not rain. The government has allocated 52 lakh tonne of rice for ethanol in 2024-25, with a target of 90 lakh tonnes the following year, according to a report by India Today.

GEMA counters this, saying that the grain being used is surplus and damaged stock – broken rice that cannot re-enter the food supply – and that “the water required to grow this grain has already been expended at the farm level.” This argument carries some weight. 

Converting spoiled buffer stock into fuel is actually a waste-to-wealth exercise. But it runs into a complication. The government plans to cut broken rice in ration supplies from 25 per cent to 10 per cent so that more can go to distilleries.

That’s not using extra stock. It’s redirecting it, and it affects food security quite directly.

The sugarcane problem

On sugarcane, the critique is harder to ignore. GEMA itself says maize, not sugarcane, is now the preferred raw material for ethanol, even as it cited it as “largely rain-fed.” Anjal Prakash, an Intergovernmental Panel on Climate Change (IPCC) author, told India Today that sugarcane cultivation has already stressed water tables in the regions where most ethanol plants are located. 

Swathi Seshadri of the Institute for Energy Economics and Financial Analysis (IEEFA) also told India Today that these plants are concentrated in cane-growing belts precisely because of raw material proximity. Those belts in Maharashtra and Uttar Pradesh, she said, are among India’s most groundwater-stressed.

Pertinent questions

GEMA president Dr CK Jain’s broader argument that India’s water crisis is a decades-old agricultural problem and that the ethanol industry is being unfairly blamed for it is not without merit. But it holds only if the ethanol programme is not actively encouraging farmers to grow more of the same thirsty crops that caused the problem in the first place. 

The economic case for ethanol blending in fuel is solid and should not be dismissed. Saving over Rs 1.7 lakh crore in foreign exchange, cutting crude oil imports, putting money in farmers’ pockets — these are real advantages.

But those gains do not make the water question go away. Before India pushes blending targets even higher, it needs straight answers to some basic questions. Which crops are actually being used, where exactly are those crops being grown, how much groundwater is being pulled out to grow them, and who pays the price when that water runs out?

(With inputs from India Today and ChiniMandi)