Rajiv Dhawan’s take on India’s Journey Toward Biomass Co-Firing
Fire is sacred in Indian tradition – Agni, the eternal flame, is regarded as the purest of the five elements. It is uncorrupted, uncorruptible, and revered as a carrier of transformation – physical, spiritual, and now, industrial. Today, fire lights not just lamps and hearths, but also our ambition to decarbonise the future. One of the most promising ways we are doing that is through biomass co-firing, where the old-world familiarity of crop residue meets the rigour of large-scale energy systems.
The Ancient Spark: Biomass as a Source of Power
The story of biomass begins with the discovery of fire itself – man’s first fuel was wood, leaves, and agricultural waste. In India, where agriculture remains the backbone of rural livelihoods, biomass has always been abundant. But the true challenge has been how to harness this potential for industrial-scale energy generation.
In rural Maharashtra, traditional sugarcane farming communities have long used bagasse – a byproduct of sugar processing – as fuel for village-scale power generation in cooperative-run Sugar mills. Today, some of these cooperatives are formalising partnerships with energy companies to supply bagasse briquettes to nearby thermal plants.
Biomass in its natural form is bulky, fibrous, and inconsistent. Converting it into a usable form for thermal power plants requires both ingenuity and infrastructure, particularly when we aim to replace coal, even partially, in a country where 70% of electricity is still coal-generated.
From Stubble to Steam: The Modern Push for Co-Firing
In 2018, the Government of India mandated a 5-10% co-firing of biomass in thermal power stations, scaling up to 30% by 2030. The goal? To reduce emissions, curb the practice of stubble burning, and create a circular economy around agro-waste.
Under initiatives like the National Bioenergy Mission in 2018 and the SAMARTH scheme (Sustainable Agrarian Mission on use of Agro Residue in Thermal Power Plants) in 2021, the procurement, handling, and feeding of biomass into boilers have seen a nationwide push.
NTPC Dadri in Uttar Pradesh was among the first power stations to successfully co-fire biomass with coal. It began trials using paddy straw pellets from nearby fields, significantly reducing local air pollution during peak stubble-burning seasons. This project became a pilot model for the SAMARTH scheme, highlighting the feasibility of large-scale agro-residue use.
As of 2023, around 39 thermal power plants in India have begun co-firing biomass, consuming over 1.7 million tonnes. But this is still far from the estimated 15 million tonnes/year needed by 2030.
What’s holding us back? The answer lies in logistics, technology, and ground-level execution.
Bridging the Gap: From Field to Furnace
To co-fire efficiently, power plants require clean, dry, energy-dense biomass delivered predictably. This has given rise to specialised handling systems – some of which I’ve had the opportunity to develop and oversee. Here’s what’s working:
1. Baling and Debaling Systems
Loose straw is difficult to store and even harder to transport. Baling compacts it into manageable units, reducing volume by up to 80%. These bales can then be debaled automatically before feeding, making the entire operation seamless and scalable. In Punjab and Haryana, where over 25 million tonnes of paddy straw is produced annually, baling is now a cornerstone of biomass logistics.
In Nabha, Punjab, the government incentivised equipment hiring centres to provide balers to farmers at subsidised rates. Farmer cooperatives now supply compressed paddy straw bales to plants like Rajpura Thermal Power Station, reducing stubble burning and generating extra income. This decentralised model is helping scale operations without centralising biomass collection.
2. Conveying and Feeding Systems
Biomass varies significantly in bulk density, particle size, and flow characteristics, making customised handling solutions essential. Vibratory feeders are commonly used for lighter, fibrous materials like paddy straw, ensuring steady flow without bridging or clogging. In contrast, screw conveyors are well-suited for denser biomass such as bagasse or biomass pellets, offering controlled and consistent movement through enclosed systems.
In high-throughput plants, the handling capacity can reach up to 50 tonnes per hour, necessitating precise engineering to prevent material jamming, reduce wear, and minimise downtime. Incorporating features like variable speed drives, hard-faced screw flights, and modular design further enhances operational efficiency and system longevity.
JSW Energy, operating in industrial belts of Karnataka and Maharashtra, adopted custom screw conveyors with variable pitch screws for handling mixed biomass – including cotton stalks and wood chips. They faced initial clogging issues due to heterogeneous material, which were resolved through trial-based modifications to screw geometry and casing design.
3. Pelletizing and Briquetting
In addition to bales, pellets, and briquettes offer uniformity and high calorific value. Their use is growing across India, with the biomass pellet market projected to grow at 12% CAGR till 2025. NTPC and other leading power producers have already committed to long-term pellet procurement.
NTPC consistently publishes biomass procurement tenders on the Government e-Marketplace (GeM) portal. This benefits micro pelletizing units, particularly in states like Uttar Pradesh, Bihar, and Chhattisgarh. For example, a supplier in Basti, UP, producing 20 tonnes of biomass pellets daily from rice husk and mustard stalks, employs over 50 locals and supplies under long-term contracts to NTPC’s Tanda unit. NTPC Tanda recently achieved a milestone of 20% torrefied biomass co-firing.
4. Storage and Automation
Modern biomass systems now include silos with automated extraction, capable of holding up to 1000 m³ of material. Automation reduces labour costs by up to 40% while improving reliability. Dust suppression, too, has become critical—not just for safety but also to meet environmental standards.
At Maharashtra State Power Generation Company’s (Mahagenco) Koradi plant, new automated biomass silos were installed with level sensors, screw feeders, and dust suppression misting. This upgrade reduced manual handling risks and ensured smoother blending with coal, helping meet air quality norms during biomass trials in 2022.
From Crop Residue to Circular Economy – The Way Forward
India’s agricultural economy produces an estimated 500 million tonnes of crop residue annually. Yet only a fraction of this is being converted to energy. With better infrastructure, smart policy, and private-sector participation, this gap can – and must – be bridged.
In Madhya Pradesh, Holcim India (ACC) has started using biomass briquettes made from cotton stalks and groundnut shells in its cement kilns under its waste heat recovery and sustainability program. This represents cross-sector industrial co-firing, where thermal energy applications extend beyond power plants to other energy-intensive industries.
As someone deeply involved in developing material handling solutions tailored to India’s agro-residues, I believe that co-firing isn’t just a policy directive; it’s a powerful symbol. A symbol that fire, long held sacred, can once again lead us—this time, toward sustainability.
Let’s keep that fire burning.
Author:
Rajiv Dhawan
Managing Director
Rollcon Technofab India Pvt. Ltd.
