Rigorous LCA

A rigorous LCA has to be made according to the ISO 14040 series (especially 14044: 2006). The Handbook on Life Cycle Assessment of the EU (see tab data > references 7.1) provides the “translation” of these ISO definitions in a comprehensive guide for experts
This webpage is not meant to replace this Handbook, but gives a general introduction on the subject for non-specialists so they will understand the main principles. A practical guide for non-specialist is available at https://www.delftacademicpress.nl/b018.php .

For some (simplified) definitions, see see Fig. 5.2a. Three aspects of these definitions are important:
– the difference between LCI and LCA
– the difference between LCA and LCC
– how to deal with “from cradle to gave” in real life calculations

An LCI is not more and not less than the result of a mass balances and an energy balances of the system, as it is common practice (already for many decennia) in chemical engineering. Essential is a choice of proper boundary limits of the system which is studied.

Figure 5.2a. Some definitions in LCA

In the classical approach, special software is needed to add-up all LCIs of the sub-systems (Open LCA, Simapro), and after that analyze the big (total) inventory list. The issue is here that such an inventory list comprises often 500 – 2000 emissions, so a method is needed to compress this long list in some indicators that do make sense to the LCA practitioner.
There are a few methods to combine the substances

Content

of the long total list to one or a few indicators. The basic idea is that the substances are combined according their effect in nature (Carbon footprint, Acidification, Eutrification), the effect in terms of human health (toxicity, fine dust, COPD), or the effect on resource scarcity  (metals, water, land-use). Nature, human health, and resource scarcity, are called ‘Areas of Protection’. The level under AoPs (carbon footprint, acidification etc.) are called ‘midpoints’.