In recent decades, life cycle assessment (LCA) has become a commonly used approach worldwide when studying environmental impacts linked to waste management systems. These systems are of a complex nature which includes everything from technical solutions, the environmental influence, and various stakeholders. To facilitate studies within this area of research, different LCA models are often utilised. WAMPS is a software specifically developed for assessing the environmental and economic impacts for a waste management system. During recent years, the work to bring the model up to date has begun as the software has not been modernised since it was developed in the early 2000s. The purpose of this degree project is to propose new emission factors for recycling and virgin production of glass, aluminium, steel, and plastic. In addition to this, the study intends to investigate how the implementation of the new figures may affect the results obtained in WAMPS.  To fulfil the purpose of the thesis, LCI datasets were collected for each material and evaluated according to three DQIs (Temporal representativeness, geographical representativeness, and documentation). New emission factors were developed based on the evaluation and discussions within the project group, to ensure that all relevant activities of the studied life cycles were included. The implications from implementing the new emission factors were investigated through a comparison with the old values. This was conducted through comparing the obtained results from WAMPS per one tonne of material as well as for a simple scenario.  The evaluation of the collected LCI data shows that many of the datasets represent average production in countries within Europe and that the data were generally older than five years old. The results show that the datasets were primarily well documented according to the criterion utilised in this study. Processes from EcoInvent were mainly used to develop the proposed emission factors. The implementation of the new emission factors in WAMPS resulted in significant change in potential environmental impact per tonne of material. Especially for the impact category photooxidation formation. For the scenario, the results indicated that a significant change in potential environmental burden is received when implementing the new emission factors. A reduction in total impact was obtained for all categories where eutrophication showed the largest absolute difference.  The developed emission factors are considered appropriate based on the design of this thesis. However, it is concluded that these have several limitations that are important to take into account if these were to be implemented in WAMPS in the future. In addition, it is considered established that an update may be considered reasonable based on the result obtained. / Under de senaste decennierna har livscykelanalys (LCA) blivit ett vanligt tillvägagångssätt världen över vid analyser av potentiella miljöeffekter kopplade till avfallshanteringssystem. Dessa system är av komplex natur och inkluderar allt från teknologiska lösningar, miljöpåverkan samt flera intressenter. För att underlätta dessa studier används idag ofta olika LCA-modeller. WAMPS är ett program som är särskilt utvecklad för att bedöma både miljömässiga- och ekonomiska konsekvenser kopplat till avfallshanteringssystem. Under de senaste åren har arbetet med att uppdatera modellen påbörjat eftersom programvaran inte har uppdaterats sedan början av 2000-talet. Syftet med detta examensarbete är att föreslå nya emissionsfaktorer för återvinning och jungfrulig produktion av glas, aluminium, stål, och plast. Utöver detta avser studien att studera hur implementeringen av de nya siffrorna inverkar på resultatet som erhålls i WAMPS.  För att uppfylla tesen av detta arbete samlades LCI data in för varje material och utvärderades enligt tre DQI:er (Temporal representativitet, geografisk representativitet och dokumentation). Nya utsläppsfaktorer utvecklades baserat på utvärderingen och genom diskussioner inom projektgruppen. Framförallt för att säkerhetsställa att alla relevanta aktiviteter i de studerade livscyklerna är inkluderade. Konsekvenserna av implementeringen av utsläppsfaktorerna undersöktes genom en jämförelse av resultat som erhölls i WAMPS då de nya samt de tidigare faktorerna nyttjas. Detta gjordes både per ton material samt genom ett enkelt scenario.  Utvärderingen av den insamlade LCI datan påvisar att många av dataseten representerar genomsnittlig produktion inom Europa och att datan generellt var insamlad för minst 5 år sedan. Resultatet påvisar att dataseten är väldokumenterad enlig indikatorn som ställts upp i denna studie. Främst användes processer från EcoInvent för att utveckla de nya emissionsfaktorerna. Implementeringen av emissionsfaktorerna i WAMPS resulterade i signifikanta skillnader i potentiell miljöpåverkan per ton material, främst för bildning av fotooxid. För fallet med scenariot indikerade studiens resultat att en betydande förändring av den potentiella miljöbelastningen erhålls när de nya utsläppsfaktorerna implementeras. Dessutom påvisades en minskning av miljöeffekterna för alla kategorier varav eutrofiering visade den största absoluta skillnaden.  Slutligen anses de utvecklade emissions faktorerna vara lämpliga utifrån utformningen av denna tes. Dock dras slutsatsen att dessa har flertalet begränsningar som är viktiga att ta i hänsyn ifall dessa implementeras i WAMPS i framtiden. Dessutom anses det vara fastställt att en fortsatt uppdatering kan anses rimlig utifrån det erhållna resultatet.

This thesis covers primarily the detection of operating emission of an old Škoda Felicia car and the emission produced during the manufacturing of a new Toyota Prius, as the selected representative of an ecological car. The thesis also touches on hybrid technology in itself, the question of the greenness of hybrid cars, sphere of emission, but also related problems so called "scrapping" and its influence on environment and also current situation in automobile industry. The target of this study is calculation of operation time of an old Škoda Felicia during which the CO2 emission will reach the same amount of emission produced during manufacturing of a Toyota Prius. The objective is to point out incompetent and therefore not always serious comparison of cars greenness when only the operating CO2 is being compared. Other energy consumption and therefore also the greenhouse gases production is related with the car manufacturing, raw material extraction, petroleum processing and other economic sectors affected by production. Emission laboratory measurement executed by TÜV SÜD Czech discovered that the old Škoda produces 260m/km CO2 during its real running time. For the emission calculation was used an American model EIO-LCA created by Green Design Institute at Carnegie Mellon University that records ecological influence of car production, in stated amount, on all economy sectors. The outputs are quoted in CO2 equivalent. According to this model during manufacturing of 1 hybrid car 13.5 t of CO2e (equivalent CO2). is produced. Recalculation found out that the old Škoda Felicia could run for more than 5 years in order to produce as much emission as the manufacturing of new Toyota Prius third generation.