Biogas electricity is the single largest carbon offset for land-applied biosolids.

This offset varies with primary-to-WAS ratio, SRT, sludge age and WWTP technology.

Transport impacts are smaller than total fugitive GHG emissions in the plant.

The fertiliser substitution offset depends on the use of total or available nutrient values.

Soil carbon sequestration credits are important for land-applied biosolids LCAs.