How should a Sangli sugar mill distillery count methane from spentwash digesters?
Biogas burnt in the boiler gives biogenic CO2, reported separately, but methane that escapes from digesters, leaks or open lagoons counts in Scope 1 at its full warming effect. Measure biogas produced and burnt; the gap, plus any flaring losses, is where the Scope 1 methane is.
Where methane escapes
- Digester leaks and pressure relief.
- Open lagoons holding spentwash before treatment.
- Incomplete combustion in flares.
How to estimate
Biogas flow meters on the digester outlet and boiler inlet give the gap. For open lagoons, use IPCC wastewater methods based on chemical oxygen demand, labelled as estimates.
Good news to record
Capturing biogas that replaces coal in the boiler cuts fossil Scope 1, and well-run digesters may support offset projects under approved methodologies.
What Senseible does here
Senseible reads fuel, electricity and production documents into dated, fingerprinted plant records, so the monthly intensity behind a figure can be traced to its source.
Sources: IPCC 2006 Guidelines for National Greenhouse Gas Inventories, IPCC AR6 Working Group I, GHG Protocol Corporate Standard
Last reviewed 2026-10-22.