Biogenic emissions are carbon released as carbon dioxide or methane from combustion or decomposition of biomass or biobased products. Per ISO 14067, we calculate biogenic carbon emissions separately from fossil based emissions. Biogenic carbon is accounted for in two main areas:
Combustion of biomass fuel
Emissions of food waste during manufacturing
Combustion of biomass fuel:
For any processing, manufacturing, or packaging processes which use a biomass fuel, biomass emissions are calculated in the same way as fossil based carbon:
Biogenic CO2e = biomass fuel required per kg of product x EF
Biogenic emissions from food waste:
During manufacturing, there is typically food waste. Where customer data is available, we can account for the exact loss in the system. When customer data is not available, we assume 5% loss of ingredients during product manufacturing. 42.6% of the loss is assumed to be anaerobically digested and 2.5% assumed to be landfilled (Source EPA). The emissions from decomposition are calculated as:
Biogenic CO2e = โ (total mass of waste ร proportion of total waste being treated by waste treatment method ร emission factor of waste treatment method )
Biogenic carbon calculations are rolled up into a single value for 2 system boundaries: cradle to gate and cradle to shelf.
Cradle to Gate biogenic emissions = (processing biogenic emissions + manufacturing biogenic emissions) * 1.05 + manufacturing waste emissions
Cradle to shelf biogenic emissions = (processing biogenic emissions + manufacturing biogenic emissions) * 1.05 + manufacturing waste emissions + packaging biogenic emissions
Any other biogenic emissions not mentioned in this phase or previous phases are excluded, including biogenic emissions on farm (see farm to farm gate section for more details).