India: Fuels
Background
Regulation of fuel properties in India began in 1990s as a direct response to worsening urban air pollution. Early efforts focused primarily on phasing out lead with a nationwide mandate for unleaded gasoline emerging by 2000. In 2000, India established its own Bharat Stage (BS) emission and fuel standards based on the European regulatory template. Guided by the Auto Fuel Policy of 2003, new requirements were first introduced in Delhi and other major cities, followed by nationwide implementation. More details on the implementation schedule of European specifications are given in the article on vehicle emission standards.
Compliance with automotive fuel standards is mandatory in India. The Bureau of Indian Standards (BIS) develops standards for automotive fuels such as IS 1460 for diesel and IS 2796 for gasoline which are then codified into nationwide mandates under the Environment (Protection) Act of 1986.
Diesel Fuel
The evolution of important diesel fuel parameters is summarized in Table 1.
| Date | Particulars |
|---|---|
| 1995 | Cetane number: 45; Sulfur: 1% |
| 1996 | Sulfur: 0.5% (Delhi + selected cities) |
| 1998 | Sulfur: 0.25% (Delhi) |
| 1999 | Sulfur: 0.05% (Delhi, limited supply) |
| 2000 | Cetane number: 48; Sulfur: 0.25% (Nationwide) |
| 2001 | Sulfur: 0.05% (Delhi + selected cities) |
| 2005 | Sulfur: 350 ppm (BS III/Euro 3; selected areas) |
| 2010 | Sulfur: 350 ppm (BS III/Euro 3; nationwide) |
| 2010 | Sulfur: 50 ppm (BS IV/Euro 4; selected areas) |
| 2020 | Sulfur: 10 ppm (BS V/Euro 5; nationwide) |
Automotive diesel fuel properties, including blends with biodiesel to B7, are covered by Indian Standard IS 1460. Biodiesel (B100) is covered by IS 15607 while blends from B8 to B20 are covered by IS 16531.
High Flash High Speed Diesel (HFHSD) IS 16861 is primarily for marine use including use by the Indian Navy, merchant ships, fishing vessels and other vessels that require a high flash point (66°C min.) fuel. It can also be used in non-automotive land-based applications. IS 16861:2018 limits sulfur to 0.2%.
Gas Oil IS 17789 is a refinery intermediate used as a diesel blend stock, feed for steam crackers and as a blend component in heating oil, fuel oil and marine fuels. This standard is intended to cater to the requirements of revenue authorities for classifying the product and to help in monitoring the quality it imports.
Distillate Marine Fuel IS 16731 covers distillate marine fuels and their blends with FAME. It aligns with ISO 8217 specifications for DMX, DMA, DFA, DMZ, DFZ, DMB and DFB category fuels.
Light Diesel Oil (LDO) IS 15770 was included in IS 1460 prior to 2005 after which it was removed and issued as IS 15770:2008. At that time, it was used in some nonroad applications such as medium and slow speed diesel engines used in earth moving equipment, pumps, power generation, marine engines, as well as heating applications. When it was revised in 2021, it was primarily used in industrial applications for heating (boilers, heaters and furnaces) and as a start-up fuel in power plants and no longer intended for internal combustion engines. IS 15770:2021 limits sulfur to 1.5%.
Gasoline
Gasoline up to E10 is covered by IS 2796. IS 2796:2017 covered eight grades of gasoline combining two octane grades (91 or 95 RON) two sulfur levels (BS IV or BS VI at 50 or 10 mg/kg respectively) and two ethanol levels (none or 5% and 10%). Fuel without ethanol or with 5.0% ethanol is called Motor Gasoline (MG) while fuel with 10% ethanol is called Ethanol Blended Motor Gasoline (EBMG). When it was issued, some areas of the country required 5.0 or 10% ethanol to be blended into gasoline. IS 2796 only allows three options for ethanol blend level: 0, 5% or 10% and blend levels between these values, e.g., 7% are not covered.
Gasoline with 20% ethanol is covered by IS 17021. IS 17021:2018 covers four grades of E20 EBMG combining two octane grades (95 or 98 RON) and two sulfur levels (BS IV or BS VI).
IS 19850 is for E22, E25, E27, and E30 blends. It was Notified in May 2026 to support India's goal of achieving a 30% blending target (E30) by 2030.
Liquefied Petroleum Gas (LPG) for automotive applications is covered by IS 14861.
Natural Gas
For natural gas vehicles, IS 15958 covers CNG and LNG. IS 15958 was first issued in 2012 as a CNG specification. LNG was incorporated in 2023. A single set of limits is specified for both CNG and LNG. A minimum methane content of 90.0% is required.
Renewable Fuels
India’s renewable fuels policy has primarily focused on ethanol blending in gasoline. After a 2001 pilot program, a 2003 E5 blending mandate in sugarcane producing states was expanded to most of the country in 2006. However, logistical challenges and inter-state taxes meant that the actual blend levels remained below the target.
National Policy on Biofuels (2009) was launched by The Ministry of New and Renewable Energy and proposed an aspirational target of 20% blending for both ethanol and biodiesel by 2017. However, the policy failed to achieve the 2017 target and the average actual blend levels for that year were 1.9% ethanol in gasoline and 0.1% biodiesel in diesel. The failure was attributed to severe feedstock scarcity and regulatory hurdles.
The National Policy on Biofuels 2018 sought to address many of the shortcomings of the previous policy and targeted blend targets of 20% ethanol in gasoline and 5% biodiesel in diesel by 2030 [6815].
By May 2022, a national average ethanol blend level of 10% was achieved and the National Policy on Biofuels 2018 was amended to bring the E20 goal forward from 2030 to 2025. A blend level of 20% was achieved in June 2025 with the 2025 consumption of fuel ethanol reaching about 10.4 billion liters.
A blend level of 30% ethanol in gasoline by 2030 is likely to be the next target. In May 2026, the Bureau of Indian Standards (BIS) officially published IS 19850:2026, a new standard for ethanol-gasoline blends of E22, E25, E27, and E30. There are also moves to promote the use of E85 and E100.
The 5% biodiesel blending target for 2030 will be challenging to meet. The 2025 blend level was estimated at 0.7%. India’s biodiesel production is based on feedstocks such as animal fats, non-edible oils, used cooking oil (UCO), and imported palm oil and palm stearin. Restrictions on feedstock imports and the lack of a cost-effective, large-scale UCO collection system are some of the challenges to increasing production from 718 million L/y in 2025 to an estimated 4.5 billion L/y required to meet a 5% blend level by 2030. One measure to address the challenge of blending renewable fuel into the diesel pool is reflected in a 2026 announcement by the Union Road Transport and Highways Minister to enable up to 15% isobutanol to be blended into diesel fuel [6814].
Efforts to promote sustainable aviation fuel are also ongoing. The government has mandated that international flights use 1% SAF by 2027, rising to 5% by 2030. There are also plans to promote renewable marine fuels under Maritime India Vision 2030 and Amrit Kaal Vision 2047 that include policies promoting renewable hydrogen, ammonia, methanol, and biofuels for shipping [6813].