NEW DELHI: India builds some of the world’s fastest expanding highway networks but depends on imports for a large share of the bitumen used to bind asphalt.
The country needs about 9 million tonnes of bitumen each year for road construction. In FY25, domestic production was 5.3 million tonnes, with the rest imported—largely from West Asia, a region currently facing conflict.
Against this backdrop, bio-bitumen, an alternative derived from biomass, could replace up to a third of petroleum-based bitumen, potentially reducing India’s import dependence. Mint explains.
How is bio-bitumen different from petroleum-based asphalt?
Conventional bitumen is a heavy residue left over after crude oil is refined into fuels such as petrol and diesel. It acts as the binding material in asphalt, holding together aggregates such as gravel and sand to form road surfaces.
Bio-bitumen, by contrast, is produced from biomass-derived materials rather than crude oil. The most common feedstocks include lignin (a plant-based polymer), vegetable oils, forestry residues and agricultural waste such as rice straw. These materials are processed through technologies such as pyrolysis, which converts biomass into bio-oil and other compounds that can be refined into asphalt binders.
In India, government research bodies such as CSIR-Central Road Research Institute (CSIR-CRRI) have been developing bio-bitumen formulations using crop residues like paddy straw, which could address both road construction demand and the problem of agricultural waste burning.
CSIR-CRRI also piloted its paddy straw-based bio-bitumen in October 2024 on NH6 Jorabat-Shillong Expressway. It showed “satisfactory field performance under traffic”, CSIR-CRRI said. According to the state-run research institute, using its paddy straw-based bio-bitumen could result in annual forex savings of ₹4,000-4,500 crore, and reduce greenhouse gas emissions in road construction by 70%.
India imports bitumen worth ₹25,000-30,000 crore annually, according to a department of science and technology statement in January 2026.
Is bio-bitumen more expensive than petroleum-based asphalt?
Petroleum bitumen benefits from established refinery infrastructure and global supply chains. Bio-bitumen, by contrast, is still produced largely at pilot scale.
Oil-based bitumen costs about ₹40,000-60,000 per tonne, depending on its quality.
Petroleum-based bitumen costs ₹50 per kg, while that of paddy straw-based bio-bitumen was ₹40 per kg, according to road transport and highways minister Nitin Gadkari in the Rajya Sabha in August 2024.
The abundance of agricultural residues may provide a low-cost feedstock base and benefit the country’s agriculture sector, Gadkari had said in his verbal response.
He also said the government would allow blending of lignin in petroleum bitumen up to 35% to reduce import costs and create opportunities for Indian farmers.
Will supply risks from West Asia accelerate India’s shift toward bio-bitumen?
It is important to understand that India’s import dependence is not limited to bitumen shipped from West Asia. The dependence also lies in crude oil imports from West Asia and other regions, which are used in domestic refineries, where bitumen is a byproduct.
Domain experts said the ongoing disruption in the region could prompt road builders to push for further innovation in bio-bitumen production. Jagannarayan Padmanabhan, senior director & global head—consulting, Crisil Intelligence said Indian highway builders are already facing bitumen price hikes, which could command a harder look at options other than petroleum-based bitumen.
Indian oil marketing companies usually revise their prices for all petroleum products every fortnight, but owing to the war situation today, they have hiked bitumen prices by nearly ₹1,000 per tonne only four days after the last revision on 1 March, he said.
“The highway industry expects such revisions to continue till the Hormuz straits clear and the war ends. The industry may increase its efforts on innovations—such as recycling of bitumen pavements (Recycled Asphalt Pavement), using waste plastic additives, and exploring the recently launched bio-bitumen,” he said.
What challenges could slow the adoption of bio-bitumen?
While bio-bitumen is emerging as a potential alternative, it is not the only way to make road construction more sustainable. Researchers and industry players are also experimenting with plastic roads, steel slag roads and other recycled materials in public infrastructure.
Bio-bitumen is still at an early stage of testing and commercial adoption. Another challenge lies in the biogenic nature of the material. Bio-bitumen derived from rice straw can be chemically different from that produced from wood waste or other biomass, which may complicate efforts to develop uniform technical standards for its use in road construction.