Greenhouse Gas Emissions from Waste
Solid waste generated from personal activities end up in solid waste disposal sites (SWDS), where methane is generated. This is why emissions from solid waste is categorized as Scope 3, because the emissions are indirect. The estimation method used is called the Mass Balance Method. The formula is:
CH4 emissions = MSWT × MSWF × MCF × DOC × DOCF × F × (16 / 12) × (1 - R) × (1 - OX)
MSWT = total municipal solid waste generated
MSWF = fraction of MSW disposed to SWD sites (assumed to be 1.0 in this calculator)
MCF = methane correction factor
DOC = degradable organic carbon
DOCF = fraction of DOC that is degraded
F = Fraction of methane in landfill gas
16/12 = stoichiometric ratio between methane and carbon
R = fraction of methane recovered
OX = oxidation factor
Default values used for MCF, DOC, DOCF and F are from the IPCC Guidelines, Volume 5 and the National Solid Waste Management Report (2008 - 2018) by the DENR-EMB. R and OX are assumed to be zero.
The resulting methane emissions must be multiplied by the Global Warming Potential (GWP) to express the results in CO2 equivalent. GWP values used in this calculator are based on the IPCC Fourth Assessment Report.