LCA Food 2012 in Saint Malo, France! - Manifestations et colloques ...

PARALLEL SESSION 6B: FISHIERIES, SOIL, AND EMERGY METHODS 8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
sary directly or indirectly to obtain a certain good or service.” (Odum, 1996). In eMergy, the term Unit
Emergy Value (UEV) (i.e. usually named trasformity,in seJ/J, or specific eMergy, in seJ/g), defines the
eMergy necessary to obtain one unit of product or service (Odum, 1996), representing the coefficient through
which different types of energy are converted to solar energy. Every biotic and abiotic resource in the geobiosphere
can be evaluated in eMergy terms and can be accounted for within the system’s output. Emergy
can be considered as an “energy memory”, i.e. a memory of all solar energy necessary to support a defined
system, considering the environmental work required previously for the production. In eMergy every life
cycle input to the system is multiplied by the corresponding UEV and the resulting eMergy flows are added
to obtain the total eMergy flow of the output. This last value is divided by the product of the considered
process (i.e. annual quantity of olive oil and wine per hectare here) to obtain its UEV, which in the classical
eMergy method is considered as an environmental performance’s index for comparison of products: the
higher the UEV, the higher is the equivalent solar energy demand per unit of product and thus lower is the
life-cycle resource consumption’s efficiency to generate that product. This study refers to the 9.26E+24 sej/J
baseline (Campbell, 2000).
2.3 Case studies: wine and olive oil productions
The selected farms are all located in the centre of Tuscany. The organic wine farm (hereafter OW) had a
vineyard of 10 ha and an average production of 3500L/ha per year (Chianti Colli Senesi wine). The conventional
winery (hereafter CW) presented a semi-industrial management that covered an area of 120 ha and
produced about 2200 L/ha of wine per year (Nobile di Montepulciano CGOD wine). CW presented a lower
yield in wine production because of a rigorous selection of grapes; in fact, in order to improve the quality of
the final product, only half of all the grapes harvested by CW are generally suitable for wine production. The
two farms were selected because of the same price of the wine bottle at the market. For both farms the production
chain can be divided in three phases: planting and production (Phase 1), wine-making and storage
(Phase 2) and bottling (Phase 3). Concerning olive oil production, the organic farm (hereafter OO) extended
for 4 ha, while the annual average yield of olives was 1500 kg/ha with annual production of 250 kg of oil.
With regard to the conventional farm (hereafter CO), olive cultivation extended for 20 ha, whereas the conduction
was directed towards an intensive production management, characterised by hard mechanisation and
chemicals use. The annual mean production was 3820 kg/ha of olives, which are processed in 483 kg of oil
per year (Protected Geographical Indication, PGI, quality). Similarly to wine, these two farms were also selected
because of the same price of one olive oil bottle at market. However, the olive oil production was divided
into two phases: agricultural phase (Phase 1) and oil mill phase, including bottling phase (Phase 2).
Inventory data (the same used for LCA and EME) for both wine and olive oil productions are showed in the
third and fourth columns, respectively, of the corresponding eMergy tables (see Tables 2 and 4).
3. Results
3.1. Wine LCA results
The comparison of the impacts characterisation of the two wine life cycles (Table 1) shows meaningful
differences, highlighting that major values are connected to CW. The major departures were found for the
packaging phase for both managements (average 50% for the 4 impact categories), with the higher values
recorded by the CW. Concerning phase 1 (planting and production) and 2 (storage), the higher values are
related to OW.
Table 1. LCIA of conventional (CW) and organic (OW) wine productions. Data reported for functional unit
(1 L bottled wine).
Impact category unit conventional wine (CW) organic wine (OW)
AP kg SO2 eq. 6,00E-03 4,00E-03
EP kg PO4 eq. 9,80E-04 6,40E-04
GWP100 kg CO2 eq. 7,30E-01 4,80E-01
POP kg C2H4 eq. 2,40E-04 1,50E-04
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