Biogases as alternate fuels
Biogas is a renewable, methane-rich fuel produced from organic waste (manure, sewage, food waste) via anaerobic digestion, serving as a sustainable alternative to fossil fuels for electricity, heating, and transport. When purified into biomethane, it functions as a drop-in replacement for natural gas (CNG/LNG), reducing greenhouse gas emissions. 
Key Aspects of Biogas as Alternative Fuel:
  • Production Methods: Generated in biodigesters or landfill gas recovery systems where microorganisms break down organic matter.
  • Composition & Quality: Contains 50-70% methane (\(CH_{4}\)) and 30-40% carbon dioxide (\(CO_{2}\)). Upgrading it removes \(CO_{2}\) and impurities to produce Bio-CNG (>90% methane) for vehicular use.
  • Applications:
    • Transportation: Compressed Bio-Gas (CBG) acts as a direct substitute for CNG in vehicles.
    • Power & Heat: Used in engines to generate electricity, run machinery, or provide cooking fuel (replacing LPG).
    • Industrial Use: Serves as a renewable energy source for heat production.
  • Environmental Impact: It aids in waste management, reduces reliance on imported fuels, and provides a circular economy solution, as it turns waste into energy.
  • Byproduct Benefits: The process yields digestate, a nutrient-rich byproduct usable as organic fertilizer. 
Key Initiatives & Trends (2026):
  • GOBARdhan Scheme (India): Aims to convert bio-waste into energy, promoting sustainable waste management and rural energy access.
  • Renewable Fuel Standards: Biogas, as Renewable Natural Gas (RNG), is recognized as an advanced biofuel.
  • Engine Modifications: Future trends focus on optimizing engines for biogas use, considering its lower heating value compared to traditional natural gas