Decarbonizing India’s road transport sector: Shouldn’t we aim higher?

The fifth in a blog series focused on our meta-study of India’s road transport emissions analyses.

Having closely studied the assumptions of the various emissions models (all detailed in the first, introductory blog), we can say with confidence that there are many policy avenues that remain unexplored from a decarbonization perspective. Many of the models don’t incorporate the entire set of emission reduction strategies already commonly employed, and thus these in no way set a boundary as far as what India can achieve. For instance, ICCT’s High Ambition scenario relies primarily on a few decarbonization strategies—fuel efficiency improvement, electrification, and alternative fuels like biofuel.  

But focusing on just a few strategies means leaving out measures like demand management and mode shift to public transport, both of which can play an important role in lowering emissions. A 2019 report, Comparison of Decarbonisation Strategies for India’s Land Transport Sector, stated that demand management and mode shift could lower carbon dioxide (CO2) emissions by 10%–20% and 4%–20%, respectively, depending on the model. These strategies and CO2 reduction numbers pertain to land transport and include both road and rail. (Separate numbers for road and rail were not available in the report.) 

Among the models we analyzed, we also found that the High Ambition scenarios were somewhat conservative in terms of assumptions about technological and policy advancement in future years. For one, in terms of fuel diversification, we mostly found mention of alternative fuels like compressed natural gas (CNG) and biofuels. Liquefied natural gas (LNG) and hydrogen were considered by only a few models and their use was expected to be trivial by mid-century. This does not seem to fit with an already evident policy shift whereby India has started encouraging the use of a variety of fuels for road transport.

Driven largely by the goal of reducing dependence on imported fuel, India’s Ministry of Road Transport and Highways (MoRTH) recently permitted the use of fuels such as CNG, HCNG (a blend of hydrogen with CNG, also called hythane), bio-CNG, liquefied petroleum gas (LPG), LNG, multiple blends of bio-ethanol with petrol, M-15 (blending 15% methanol with petrol), M-85, M-100, MD-95 (95% methanol and 5% additives), a mixture of biodiesel up to 100%, and dimethyl ether (DME or D100). The government is also considering moving up its E20 target (20% ethanol blending in petrol) from 2030 to 2025, and recently announced a plan to launch a National Hydrogen Mission, which would aim to promote the use of hydrogen in different sectors. Indian Oil Corporation and the National Thermal Power Corporation are already evaluating the deployment of hydrogen fuel cell buses in the country. 

The air and climate impacts of the various alternative fuel pathways is important. For instance, the HCNG being used at the moment in India does not offer significant climate and air quality benefits in comparison with Bharat Stage VI diesel or CNG. Additionally, hydrogen fuel is currently produced from natural gas or coal bed methane, and the methanol being considered for the transport sector will likely be sourced from coal. If the models are revised to include more of these alternate fuel options, they might offer valuable insight into the impact the different pathways could have in terms of energy and emissions from the road transport sector. That there is a fuel mix in the models currently, even in small quantities, shows that alternative fuel pathways were considered. But just considering different fuel mixes is not the same as working to identify the most efficient decarbonization trajectory for the country.

Ideally, the models should be able to evaluate the existing set of policies, and the High Ambition scenarios should further be capable of assessing ambitious policy pathways that would come about in the future. At present, though, most of the models do not capture near-term technology and policy advancements. In that sense, the models have been short-sighted and this suggests a need to be more ambitious with respect to our future and our High Ambition scenarios. Our analysis of a more aggressive decarbonization scenario suggests that lowering emissions below the levels as indicated by current High Ambition trajectories is very much possible, and perhaps reaching a well below 2°C of warming scenario might not be entirely out of reach. We’ll have more on this in our next blog, in which we will try to explore how much further the emissions curve can be bent over and how far beyond the current High Ambition scenarios we can go. We’ll also try to quantify the decarbonization benefits that would result from an Aggressive Policy scenario that pursues ambitions stronger than the High Ambition scenario.

The modeling exercises we conduct and the future we project play a critical role in informing policies and decisions. There is a need to be fiercely forward looking and envision a future with all the possible emission reduction policies and technologies. The future needs to be focused on reversing the detrimental business-as-usual trends. Only once we perceive this future can we draw a roadmap for achieving it. Without a comprehensive roadmap, India is likely to keep taking a piecemeal approach, and this will slow down its transition to  a low-carbon future and likely increase the costs of decarbonization.   

Small ambitions lead to only modest progress and that would mean a grim future for all of us. This is a call to our fellow researchers to aim for higher ambitions in transport models, because our future course of action will be determined by these. At the same time, it’s critical that transport emission mitigation targets be addressed independently in the next round of nationally determined contributions (NDCs). We as a community ought to create momentum toward realization of this goal. Big results require big ambition!

This is part of NDC Transport Initiative for Asia (NDC-TIA). NDC-TIA is part of the International Climate Initiative (IKI). The Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) supports the initiative on the basis of a decision adopted by the German Bundestag. For more visit:

Electrification Tracking progress
Clean air
Emissions modeling