Revised Classification of Compressed Biogas (CBG) Plants Under CPCB Guidelines

Introduction

The Central Pollution Control Board (CPCB) has recently revised the Classification of Compressed Biogas Plant (CBG/Bio-CNG) under its new Classification-2025 framework. Specifically, this update categorizes CBG plants into Red, Blue, and White categories based on their Pollution Index (PI) scores. Consequently, the move aims to harmonize industrial classification across India and ensure that essential environmental services, such as biogas production, align with pollution control measures. Moreover, this revision reflects an increasing focus on sustainable energy sources while addressing potential pollution risks. This blog provides a detailed breakdown of the new classification system, the rationale behind these changes, and its implications for the industry.

1. Understanding CPCB’s Classification of Compressed Biogas Plant 2025

CPCB has developed a new classification methodology based on an equal weightage system for pollution factors, including Water Pollution, Air Pollution, and Hazardous Waste. Additionally, it introduces a new Blue Category, which is distinct from the traditional Red, Orange, Green, and White categories. Notably, this classification aims to regulate essential environmental services like biogas production more effectively. Furthermore, the new system seeks to ensure uniformity in regulatory decisions across various states. By doing so, CPCB intends to enhance transparency, simplify compliance, and support sustainable industrial operations.

2. Why Was Reclassification Needed?

CBG plants utilize a variety of feedstocks, including municipal solid waste (MSW), agro-residue, energy crops, animal waste, and industrial process waste. Unfortunately, some of these materials pose significant littering and pollution risks, leading to growing concerns about their environmental impact. In response, a committee was formed to review industry representations and reassess the categorization of CBG plants accordingly. Moreover, this reclassification was necessary to differentiate between plants with varying pollution potentials. Ultimately, this process ensures that regulatory measures are better aligned with environmental risks while promoting sustainable waste management practices.

3. New Categories of Classification of Compressed Biogas Plant

🔵Blue Category (Low-Impact Environmental Services)

These plants handle organic waste but generate minimal pollution, making them suitable for the Blue Category.

CBG plants using feedstocks like MSW, agro-residue, energy crops, animal waste, and press mud, generating ≥ 50 KLD wastewater – PI Score: 82.5.
CBG plants with similar feedstocks, generating < 50 KLD wastewater – PI Score: 79.0.
CBG plants with no wastewater discharge, producing by-products like Fermented Organic Manure (FOM) and briquettes/pellets using fuel – PI Score: 60.0.

⚪ White Category (Minimal Pollution Potential)

CBG plants with no wastewater discharge, producing FOM and briquettes/pellets using electricity – PI Score: 20.0.

🔴 Red Category (High Pollution Potential)

CBG plants based on industrial process waste – PI Score: 82.5.

Overall, this new classification creates a clearer distinction between CBG plants based on their environmental impact. Additionally, industries can better assess their compliance requirements while reducing unnecessary regulatory burdens.

4. Implications of the New Classification

Industries can now clearly understand their regulatory requirements based on their pollution potential. Moreover, this updated classification allows State Pollution Control Boards (SPCBs) and Pollution Control Committees (PCCs) to standardize approvals and monitoring procedures. Additionally, CBG plants categorized under Blue will benefit from reduced regulatory burdens, whereas those in Red will face stricter compliance measures. Consequently, companies must align their processes with the new framework to ensure continued environmental compliance. In the long run, this classification not only supports sustainable energy but also strengthens pollution control initiatives.

Conclusion

The revised classification of CBG plants under CPCB’s Classification-2025 aims to streamline environmental compliance and enhance waste management practices. By clearly differentiating between essential environmental services and industrial waste-based operations, this initiative promotes sustainable energy production while ensuring effective pollution control. Furthermore, these changes simplify regulatory approvals, reduce administrative burdens, and support India’s broader environmental goals. Ultimately, industries must adapt to this framework to remain compliant, mitigate risks, and contribute to a cleaner, more sustainable future.

Download: Classification of Compressed Biogas Plant: Revised by CPCB