4. PRESENTATION AND ANALYSIS OF THE LCA RESULTS
4.7 S UMMARY AND INTERPRETATION OF THE RESULTS
The results for the different LCIA methods vary with respect to the total amount of environmental load, and the focus point, namely impact categories, where the environmental impact is the highest.
This is due to the very detailed input data. As a result, certain substances may influence the results in one method, and in the other, its importance for the final modelling outcome may be marginal.
This is true for the materials used in the production of the cooker in smaller amounts. For the main materials comprising the essential part of the appliance mass, their share in the creation of environmental load is taken into consideration in the modelling stages of all LCIA methods.
The LCIA modelling results are summarized and compared in tables 4.1 and 4.2. As one can see, the modelling results for different LCIA method are not contradictory to each other. In general, the following patterns may be recognized for all used LCIA methods:
• The materials with the highest impact on the environment are steels (high alloy, low alloy, austenitic steel), glass, and in some cases other high weight materials;
• Other materials, although present in the inventory results, play a smaller role in the overall impact on the environment;
• These materials, may, however, cause some divergence of results, when comparing outcome of modelling from different LCIA methodologies; their influence determines the environmental performance of the product especially in the less important or neglectably important impact categories;
• Generally speaking, the depletion of abiotic resources and emissions from energy generation play the major role, when discussing the impact of the KGE 3490X on the environment;
• Depletion of resources reflects environmental effects stemming from the extraction of ferro metals and use of gas reserves;
• Gaseous emissions influencing the state of the environment are associated mainly with the production of electricity for the use phase and production of ferro and non-ferro metals;
• The assemblies causing the highest environmental damage are equipment, oven, side walls, glass plate, and decorative angle;
• When the use phase is taken into consideration, the impact from the manufacturing of the product is considerable, but much smaller than the impact of the cooking and baking processes;
• The impact from the cooking processes is stemming mainly from the meals most often prepared in the Polish households (i.e. cooking of potatoes, boiling of water for the hot beverages);
• The impact from the use phase may be only predicted, since large variability of habits is present, even inside one single societal group, responding to the questionnaires;
• Impacts stemming from the usage of the upper part of the cooker (gas burners) is bigger that that of baking in the electrical oven; however, these values are comparable in their magnitudes;
• Application of recycling processes in the production phase, as well as in the EoL scenario, helps to avoid some emissions, thus minimising the total impact of the appliance on the environment.
Part C will present the results of sensitivity modelling, focused on the Polish enterprise in the context of the Environmental Managements System, with respect to the implementation of the EuP directive and the application of the LCA techniques.
Table 4.1 Comparison of the LCIA methods with respect to most important damage and impact categories, subassemblies, and materials; cooker without EoL and without use phase. For all LCIA methods, recycling processes reduced the total environmental impact.
No. Method Damage/Impact categories Subassemblies Materials/Processes Remarks
1. CML 2
Marine aquatic ecotoxicity, acidification, fresh water aquatic toxicity, human toxicity
Equipment, oven, door, glass plate
Steel high alloy, nickel, chromium, float glass, steel low alloy and electricity
-
2.
Cumulative Energy Demand
Electricity production: non-renewable fossil fuels and nuclear energy
Oven, equipment, glass plate, door, side walls, packaging, production and transportation
Steel high alloy, steel low alloy,
float glass, nickel, austenitic steel -
3. Ecopoints
97 Emission of the CO2, SOx, NOx
Oven, equipment, door, glass plate, side walls, electrical system screen, drawer
Steel high and low alloy, austenitic steel, float glass, electricity
production
-
4. EDIP/UMIP
Ecotoxicity water chronic, ecotoxicity water acute, human toxicity soil, ecotoxicity soil chronic
Oven, equipment, glass plate, door, side walls, packaging
Steel low and high alloy, float glass, sheet rolling process, austenitic steel, plastic materials
-
5.
Eco-Indicator 99
Resources; respiratory inorganics, fossil fuels. minerals, climate change, land use, ecotoxicity, carcinogens,
acidification/eutrophication
Oven, equipment, door, decorative angle, drawer, production and transportation, side walls
Steel low and high alloy, austenitic steel, float glass coated,
polystyrene, polyethylene, cleaning agent, natural gas, nickel, glass fibre, energy production
-
6. EPS 2000 Abiotic stock resource; depletion of reserves
Production and transportation module, equipment, oven, glass plate, side alls, door
Steel high and low alloy, austenitic steel, energy production, float glass
Negative values for ecosystem production capacity (fish and meat production and wood growth capacity categories)
7. IPCC -
Oven, equipment, glass plate, door, side walls, production and
transportation
Steel high alloy, steel low alloy, austenitic steel, float glass, generation of energy
Impact on the environment is slightly decreasing with the increasing time span
Table 4.2 Comparison of the LCIA methods with respect to most important damage and impact categories, subassemblies, material and meal types; KGE 3490X with EoL and with use phase. For all LCIA methods, recycling processes slightly reduced the total environmental impact.
No. Method Damage/Impact categories Meal types/Assemblies Materials/Processes Remarks
1. CML 2 Marine aquatic ecotoxicity Cooker, cakes and desserts, beverages, main course
Electricity generation,
consumption of natural gas, steel high alloy
-
2.
Cumulative Energy Demand
Energy generation, non-renewable fuels
Cakes and desserts, hot beverages, main course, side dishes, soups
Electricity generation from the hard coal and natural gas combustion
-
3. Ecopoints
97 CO2, SOx and NOx emissions Cakes and desserts, hot beverages, main course, cooker
Electricity generation,
consumption of natural gas, steel high alloy
-
4. EDIP/UMIP Ecotoxicity water chronic, Ecotoxicity water acute
Cakes and desserts, hot beverages, main course, cooker
Electricity generation,
consumption of natural gas -
5.
Eco-Indicator 99
Resources; fossil fuels, respiratory inorganics emissions
Main course, cakes and desserts, hot beverages, soups, cooker
Electricity generation,
consumption of natural gas -
6. EPS 2000 Abiotic stock resource; depletion of reserves
Cakes and desserts, main course, hot beverages, cooker
Electricity generation,
consumption of natural gas, steel high alloy
Negative values for ecosystem production capacity (fish and meat production and wood growth capacity categories)
7. IPCC - Cakes and desserts, main course,
hot beverages
Electricity generation, consumption of natural gas
Impact on the environment is slightly decreasing with the increasing time span