Page 143 - Materials Chemistry, Second Edition

3.4 Procurement, Origin and Quality of Data 127

Specific operational data Generic data record Input and output data
(primary data) for inclusion of of unit process including
5 −1
e.g. 5 × 10 kWh a pre-chain, e.g. electricity upstream pre-chain
mix, Germany

Conversion in a unit Inputs and outputs as
Data record of unit process
meaningful in LCA elementary flows:
based on elementary flows
electricity generation from
and usable in the inventory.
raw material extraction
e.g.:
to grid electricity.
/pice
1.5 MJ el
Figure 3.27 From operational data to the unit process data record.
3.4.3
Generic Data and Partial LCIs

3.4.3.1 Which Data are ‘Generic’?
The translation ‘generic’, a word of Greek origin, ‘of general concern’, indicates
that specifics are not meant. They are averages or representative single values. An
example: For each plastic production, for example, polyethene, crude oil is used,
which is processed in a refinery. It would be completely inadequate if for each
product made of plastic the primary data would have to be procured from the
refineries again and again. Besides, because of trade flows, the refinery from which
the molecules that were polymerised to specific kilograms of plastic originated
is usually not traceable. Therefore it makes sense to determine average values of
environmental loads for a type of refinery which manufactures pre-products for the
plastics industry allocated to the appropriate monomer, for example, on ethene.
The resulting data record would then be ‘a generic’ data record. For an estimate of
its usefulness it is important to include an indication of the geographical region
of the examined refineries and the time horizon of the data. In other words, the
indication of the temporal and geographical system boundary of such data records
is very important.
Similarly, the data record for the production of electrical energy (electricity mix
Germany) listed in Table 3.7, is generic. It is based on the analysis of the technology
mix of power plants applied for the production of electricity in 1996 (see data sheet
in the Appendix B).