Formula for Project and Leakage Emissions From Composting

For composting, we used default emission factors recommended by the the UNFCCC’s CDM, methodological instrument of the AMS-III.F, Tool 13, version 02.0, called “Project and leakage emissions from composting”, and they are 2.0 gCH4/kg-1 of “Fresh Weight” of waste for methane and 0.2 gN2O/kg-1 of “Fresh Weight” of waste for nitrous oxide (UNFCCC, 2017). Fresh Weight is the gross weight of a substance, i.e. including the water content.

The following equation is used to calculate emissions:

Where:

Qy = 1.0 t – food waste / 1.0 t – Garden/yard waste (Quantity of waste composted);

EFN2O = 0.2 g/kg of waste (Emission factor of nitrous oxide per kilogram of waste composted);

EFCH4 = 2.0 g/kg of waste (Emission factor of methane per kilogram of waste composted);

GWPN2O = 265 (Global Warming Potential of N2O) – IPCC, 2013; and

GWPCH4 = 28 (Global Warming Potential of CH4) – IPCC, 2013.

*Default emissions factors on a per ton basis are also utilized for fossil fuel and electric power consumption, although not shown in the simplified version of the formula presented above.