For fixed costs, annual costs (AC) [€/year] were divided by the
annual usage rate of the plant (AURp) [tonne/year], in order to
obtain fixed costs per item involved in treating one tonne of waste
(CIf) [€/tonne], whereas for variable costs the physical amounts
were the amounts of items needed to treat/dispose one tonne of
waste (IxT) [kg (or MJ)/tonne] and they were multiplied by the unit
price of the item (UPI) [€/kg (or MJ)], to obtain variable costs per
item involved in treating one tonne of waste (CIv) [€/tonne], as in
Eqs. (7) and (8). Physical amounts (for example 1 l diesel/tonne
of waste collected) can be obtained from various sources, such as
environmental reports.