Flying Colours: India is trying to turn waste into green jet fuel

IN MARCH 2007, when Colombian chemist Jennifer Holmgren said that soon there would be planes flying on biofuels just like vehicles on roads, several in the audience had apparently laughed it off. Holmgren, then director of Renewable Energy and Chemicals at UOP, a Honeywell company, was presenting a paper titled ‘A New Development in Renewable Fuels: Green Diesel’ before the National Petrochemical and Refiners Association (NPRA) annual meeting.

Just 20 months later, the idea of a plane flying using clean fuel was no longer just a chimera. Air New Zealand flew a Boeing 747, with one of its four engines powered 50 per cent by a sustainable biojet fuel derived from the Jatropha plant, sourced from India, Malawi, Mozambique, and Tanzania. The flight was a collabo­ration between Air New Zealand, Boeing, Rolls-Royce and UOP.

Holmgren, whose research turned out to be a tipping point for Sustainable Aviation Fuel (SAF) technologies that cut greenhouse gasses emitted by aeroplanes in the air, visited India in October 2007, promoting “green diesel” options. Then secretary to the Ministry of Petroleum and Natural Gas, MS Srinivasan, who attended her presentation at the Imperial Hotel in New Delhi, had announced that by 2017, 10 per cent of transport fuels would be replaced with biofuels in the country. Among the audience was interdisciplin­ary scientist Anjan Ray, who was then working with UOP. “That’s how I started,” recalls Ray, who joined as director of the Indian In­stitute of Petroleum (IIP), a laboratory of the Council of Scientific and Industrial Research (CSIR), at Dehradun, in 2016.

In 2009, the Manmohan Singh government came out with a national policy on biofuels, setting an indicative 20 per cent blend­ing target for bio-ethanol and bio-diesel by 2017. Aviation biofuel was still barely on its radar. But by 2016, the International Civil Aviation Organization (ICAO) adopted Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), forcing airlines to buy carbon offsets for international flights. To com­pensate for extra carbon pollution, planes flying between ICAO countries would have to buy carbon credits, like paying for plant­ing trees. India could no longer delay the quest for greener skies.

Ray, who was in Hanoi when CORSIA was formalised, took up the job at IIP, where the mission to make India join the pursuit for clean aviation fuel took shape. CSIR-IIP had already started its journey on biojet fuel in 2009. “A lot of work was done, but it was still at laboratory scale though industry partners were already present in the starting consortium. They were able to make the material more or less as desired, in modest quantities, but that wasn’t enough to fly a plane since many technical and regula­tory hurdles had to be surmounted,” says Ray. After he joined, the primary focus of the effort was to get a plane to fly in India with indigenously innovated biofuel blended with fossil fuel, and to get the standards approved.

“The plant within the forested campus of CSIR-IIP ran 24/7, through rain and shine, through cobras falling through the roof and leopards on the prowl outside. It ran in three shifts, just like in a factory, continuously, even through Covid. It had a fabulous

team. We are working with hydrogen at a hundred or more at­mospheres, which is very high pressure. It’s like working with a bomb that can go off any time. So the major challenge was that everything ran safely,” Ray recalls.

By August 2018, CSIR-IIP and a clutch of stakeholder-partners got a SpiceJet Bombardier Q400I turboprop plane flying with one of its two engines powered 25 per cent with fuel sourced from the oil of Jatropha trees from Chhattisgarh, while the other engine was 100 per cent Aviation Turbine Fuel (ATF). Flagged off from Dehradun, there were 20 people onboard the 55-minute flight, including Ray and two of his IIP colleagues. In January 2019, an Indian Air Force AN-32 Transport aircraft was flown with both engines running on 10 per cent fuel derived from hydrogen treat­ment of a mixture of tree-borne oil and used cooking oil. So far, the IAF has done around 70 sorties of this aircraft using SAF.

India is now awaiting certification from the US-based ASTM International, a global standards organisation, for its indigenously made SAF which has been given the acronym DILSAAF (Drop-in liquid Sustainable Aviation and Automotive Fuel). DILSAAF can be made from a range of feedstocks, including tree-borne oilseeds, non-edible oils, fish oil and tallow. “Hopefully, the ASTM approval will come by later this year. They have a rigorous process, called ASTM D4054, that covers both materials and methods for manu­facturing as well as product quality and stringent technical speci­fications,” says Ray, who has been felicitated with the Jury Choice Award for Outstanding Green Activist by the Indian Federation of Green Energy. After retiring from IIP in 2023, he continues to support activities in biofuel, renewable energies and the broader sustainability space.

DILSAAF is an innovative variant of HEFA-SPK (Hydroprocessed Esters and Fatty Acids Synthetic Parafinic Kero­sene), the most widely used technology across the world to make clean aviation fuel which cuts carbon emissions by up to 80 per cent and is fully compatible with aircraft engines. “While normal HEFA-SPK does not contain aromatic components, DILSAAF has about 8 per cent aromatics. Conventional fossil-based ATF (Jet A-1) requires 8-24 per cent aromatics. So when HEFA is used, it has to be blended with selective high-aromatic batches of ATF to make it com­pliant with existing ATF-compatible engines. This is what DILSAAF aims to overcome,” says Ray. To ensure domestic production and a robust supply chain, bulk production will begin at the Man­galore Refinery and Petrochemicals Ltd within a couple of years.

India is only the second country in the world to have flown their first SAF flight with their own fuel, says Ray. “Almost every other country, and there’s probably a dozen of them before India’s maiden flight, used American technology to fly their planes for the first time. SAF is very important for India. If we don’t have our own fuel and in a situation where there’s a prolonged problem in the Gulf or Venezuela, we would have no planes flying if there’s no crude oil reaching our shores. DILSAAF is the one indigenously developed fuel we can make in India with carbon atoms available within the country,” he adds.

WITH INDIA, WHICH evaded the voluntary phases of CORSIA, preparing to join by 2027, it has amended its ATF rules to include SAF blending targets for its airlines—1 per cent by 2027, 2 per cent by 2028 and 5 per cent by 2030. In the European Union, the mandate on SAF blending is 2 per cent in 2025, 6 per cent in 2030 and up to 70 per cent by 2050; in UK, 2 per cent in 2025, 10 per cent in 2030 and 22 per cent in 2040; Japan 10 per cent by 2030. The US is promoting SAF through production incentives.

In Europe, where studies have found that trains cause up to 80-90 per cent less carbon emissions than flights, several governments are pushing for travel by train. In India, however, where distances are more and flying is aspirational, the skies are expected to get more bustling. According to an official statement in October last year, by 2040, air passenger traffic is forecast to grow six-fold to around 1.1 billion. The commercial airline fleet is predicted to grow from 400 in 2014 to around 2,350 in March 2040 in India, which has emerged as the world’s third-largest domestic aviation market.

CORSIA has pushed aircraft man­ufacturers like Airbus and Boeing to put sustainability at the core, mak­ing it an existential question. They started thinking of how to decarbo­nise, drawing out a roadmap of multi-pronged initiatives. Besides commit­ting to SAF-compatible aircraft, they are looking at material, design and technology through the prism of the environmental footprint. Airbus is ac­celerating fleet renewal with the lat­est generation aircraft, which deliver a fuel savings of 20 per cent to 30 per cent compared to their predecessors, feature advanced aerodynamics and use lighter materials and are capable of operating on a blend of up to 50 per cent SAF. Boeing, advocating end-of-life aircraft, has an aircraft recycling programme, partnering with companies like ecube for dismantling retired aircraft and recovering valuable components for reuse. The next generation would be hydrogen-powered aircraft. Some international airlines have introduced “green fares”, offering tickets at a premium, with the additional proceeds going into offsetting carbon emissions.

A Deloitte India report forecasts India could produce 8-10 mil­lion tonnes of SAF annually by 2040, with investments worth `6-7 lakh crore. This would surpass India’s estimated domestic demand of 4.5 million tonnes for a 15 per cent blending mandate in 2040 across all flights, and could also position India as a leading SAF exporter serving global markets.

Citing ICAO, IATA (International Air Transport Association) and ATAG (Airport Transport Action group) estimate that SAF will contribute 53-66 per cent in achieving the target of net-zero carbon emissions by 2050, the report says that it will become the most important decarbonisation levers. According to it, in India, while used cooking oil could contribute a limited quantity towards SAF production, due to variation in quality, the Alcohol to Jet (Atj) using 2G ethanol derived from agricultural residues manifests as India’s most promising pathway in the near future, with Municipal Solid Waste (MSW) enhancing its output.

Three months ago, the Gati Shakti Vishwavidyalaya in Va­dodara and Airbus jointly began research on turning MSW, by breaking down garbage in the laboratory, to convert it into green jet fuel. “It will take two-three years. It’s a pilot plan. We have had a success story with road transport. This waste-to-wealth initiative will also clear the cities of landfills,” says V Chintala, associate dean (R&D), Gati Shakti Vishwavidyalaya.

In 2018, the Narendra Modi government had brought out a National Policy on Biofuels extending acceptable feedstock to include damaged foodgrains, surplus wheat, and rotten pota­toes. Carbon emissions from India’s aviation sector have been estimated to be just around 5 per cent of its transportation emis­sions, but with the sector growing and government pushing for electrification in road transportation, it is expected to rise to 8-10 per cent by 2030.

“We have made a roadmap for SAF targets till 2047. Commer­cial production is yet to begin. India, though a bit late, will be at an advantage. It is coming out with new technology with green distilleries working on ethanol. 2G ethanol can be routed to SAF,” says Sumit Sarkar, chief executive officer of the Chhattisgarh Biofuel Development Authority (CBDA).

“India has enough feedstock and we can be exporting SAF, but initial investment is needed and there have to be firm offtake agreements. Either international airline companies take initia­tive and sign pacts with Indian producers or Indian companies declare plans to produce SAF and get potential international buy­ers. It’s a chicken-and-egg story. Let’s see which happens first,” says Ajay Deshpande, ICAO India consultant, who has co-authored an ICAO India feasibility study funded by the European Union.

It says while India’s favourable geographic location positions it for export to Southeast Asia and Europe, most SAF technologies are not commercial yet and must still be demonstrated success­fully. SAF development can address challenges like air pollution as a result of burning rice straw and other wastes, provide jobs and income to farmers, while the absence of firm supportive and adequate policies makes investment in Indian SAF facilities, as yet, uneconomical, according to it.

With its production expenses higher than fossil jet fuel, cost is being seen as one of the biggest challenges to SAF. According to IATA, as with wind and solar energy markets when they were new, addressing these challenges will require supportive govern­ment policies, a coherent strategy across the energy system and close collaboration across the aviation value chain.

The Deloitte India report says 2-5 per cent of SAF blending will result in a 2-5 per cent increase in ticket prices for domestic flights and 1-3 per cent for international flights. It predicts a limited in­crease in ticket prices.

For India, SAF can bring opportune times and offer challenges. Studies and experts indicate that if done right, India can become a SAF stockhouse as the world strives to make the blue go green.