3.6. Bottom-up vs. top-down approaches
The cost model applied a bottom-up approach in which cost
items within each technology were calculated first, and then followed
by a calculation of the technology cost and finally the cost
for the entire scenario. This approach requires detailed knowledge
not only of the involved technologies but also of each specific cost
item related to a technology. While this may facilitate transparency
and a higher level of technical accuracy, the approach also
has extensive data needs. Additionally, as state-of-the-art waste
LCAs also follow a bottom-up approach, applying similar principles
in the cost assessment ensures the best possible correspondence
between the two parts of the LCC. Examples of other cost assessments
on waste management applying bottom-up approaches
include Broitman et al. (2012) and SWOLF (Levis et al., 2013).