Design for E nvironment and E nvironmental Certificate at Mercedes-Benz Cars

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1 Design for E nvironment and E nvironmental Certificate at Mercedes-Benz Cars Klaus Ruhland, Rüdiger Hoffmann, Halil Cetiner and Bruno Stark Abstract Life cycle assessment (LCA) is used as a tool for design for environment (DfE) to improve the environmental performance of the Mercedes Car Group products. For new models a brochure including an environmental certificate and comprehensive data for the product are published. This environmental certificate brochure reports on processes, data and results based on the international standards for life cycle assessment (ISO 14040/44) [1,2], for environmental labels and declarations (ISO ) and for the integration of environmental aspects into product design and development (ISO TR 14062), which are accepted by all stakeholders [3]. Furthermore, the DfE process is representing the key element of the environmental management system (ISO 14001) of the R&D organisation at Mercedes-Benz Car Group. The compliance with these international standards and the correctness of the information contained in the certificate are reviewed and certified by independent experts. In 2005, the Mercedes-Benz S-Class became the world s first automobile to receive an environmental certificate. It has now also been granted to the C-Class, the A-/B- Class, the GLK, the E-Class, the new CLS and SLK, and the S 400 HYBRID [4]. 1 Introduction If the environmental compatibility of a vehicle is to be improved, it is important that its emissions and consumption of resources is reduced throughout the whole of its life cycle. The extent of the ecological burden caused by a product is already largely defined during the early development phase. Later corrections of the product design are only possible at great cost and effort. The earlier "Design for Environment" is integrated into the development process, the greater the benefits in terms of minimising environmental effects and costs. Process- and productintegrated environmental protection must be realised during the development K. Ruhland ( ) R. Hoffmann H. Cetiner B. Stark Daimler AG, Sindelfingen, Germany klaus.ruhland@daimler.com M. Finkbeiner (ed.), Towards Life Cycle Sustainability Management, 557 DOI / _54, Springer Science+Business Media B.V. 2011

2 558 Klaus Ruhland et al. phase of a product. Later on, environmental effects can often only be reduced by downstream, end of-the-pipe measures. We develop products which are particularly environmentally compatible within their market segment this is the Daimler Group s second environmental protection guideline. The aim is to improve environmental compatibility in an objectively measurable way, while meeting the demands of the increasing number of customers who are mindful of such environmental aspects as lower fuel consumption and emissions or the use of environmentally friendly materials. The implementation of the Design for Environment Process at Mercedes-Benz will be explained in the following sections and demonstrated by the exemplary case study of the S-Class Hybrid model (S 400 HYBRID). 2 Design for environment process and organisation The responsibility for improving environmental compatibility was an integral part of the organisation of the S 400 HYBRID development project. The so-called DfE team was made up of experts from the fields of life cycle assessment, dismantling and recycling planning, materials and process engineering, as well as design and production. This guarantees complete integration of the DfE process in the vehicle development Design for Environment Process of MBC/ D certified according to ISO by TÜV Süd. Brochure documents the improvement in environmental compatibility. Fig. 1: Process design for environment and brochure environmental certificate The integration of Design for Environment into the process organisation of the S400 HYBRID development project ensured that environmental considerations would be taken into account in the early development stages, and not just prior to

3 LCM in the Mobility Sector 559 market launch. Appropriate objectives were agreed upon early on and reviewed at relevant quality gate stages during the development process. Together with the S- Class HYBRID project management, the DfE team had defined concrete environmental objectives in the areas: prohibited substances, recyclability, use of recycled plastics and renewable raw materials and reduction of all substantial environmental burdens caused by the S-Class HYBRID during its lifecycle (ecological life cycle assessment). To provide the best possible service to as many interested parties the results were documented in a brochure called Environmental Certificate. This brochure documents the clear improvements which have been achieved through the implementation of hybrid technology, as compared with the S 350 reference vehicle. Both the process of design for environment and the Environmental Certificate have been certified by independent experts according to internationally recognised standards. The process carried out for the S 400 HYBRID meets all the criteria for the integration of environmental aspects into product development which are described in ISO standard LCA results: S 400 Hybrid in comparison with S 350 Over the entire life cycle of the S 400 HYBRID, the Life Cycle Analysis calculations indicate, for example, a primary energy consumption of 1093 gigajoules (equal to the energy content of about 33.5 tonnes of premium-grade petrol) and the input into the environment of around 78 tonnes of carbon dioxide, about 32 kilograms of nonmethane hydrocarbons, about 40 kilograms of nitrogen oxides and about 68 kilograms of sulphur dioxide. In addition to the analysis of overall results, the distribution of single environmental impacts among the different phases of the life cycle is investigated. For carbon dioxide emissions and also primary energy consumption, the use phase dominates with a share of over 85 per cent. However, it is not the use of the vehicle alone which determines its environmental compatibility. Some environmentally relevant emissions are caused principally by its manufacture, for example the sulphur dioxide emissions. For this reason the manufacturing phase must be included in the analysis of ecological compatibility. For a great many emissions today, the dominant factor is not so much the vehicle operation itself, but the production of the fuel, for instance for hydrocarbons and nitrogen oxides and for the environmental impacts which they essentially entail: photochemical ozone creation potential (POCP: summer smog, ozone) and acidification potential (AP).

4 560 Klaus Ruhland et al. Parallel to the examination of the S 400 HYBRID an LCA was made of the comparable S 350 petrol engine model in the ECE basic variant version. Fig. 2: Comparison of carbon dioxide emissions - S 400 HYBRID vs. S 350 [t/car] As shown in Figure 2, the production processes for both vehicle models show similar levels of carbon dioxide emissions. But a clear advantage emerges for the S 400 HYBRID over the total life cycle. At the beginning of its life cycle, production of the S 400 HYBRID causes slightly higher carbon dioxide emissions than the S 350 reference vehicle (10.7 tonnes of carbon dioxide in total). The reason for this is the - in part - demanding production of additional components for the drive system (above all, the battery). In the operating phase which follows, comprising fuel production and vehicle operation, the S 400 HYBRID emits approximately 66 tonnes of carbon dioxide; the total, therefore, for production, operation and recycling comes to 78 tonnes of carbon dioxide. The production of the comparable S 350 with petrol engine uses 10.2 tonnes of carbon dioxide. In the operating phase, the S 350 emits 84 tonnes of carbon dioxide due to its higher fuel consumption. Carbon dioxide emissions come to about 94 tonnes in total. When looking at the total life cycle comprising

5 LCM in the Mobility Sector 561 production, operation over 300,000 kilometres and recycling - the S 400 HYBRID causes 18 per cent (16.6 tonnes) fewer carbon dioxide emissions than the S 350. In Figure 3, emission into the air and the relevant impact categories are shown compared across the individual life cycle phases. In each case, the results for the S350 in the production phase are slightly more favourable; however the S 400 HYBRID displays a clear advantage over the total life cycle. Fig. 3: Comparison of selected parameters for the S 400 HYBRID and S 350 Total consumption of resources is reduced by 18 per cent as well (ADP = abiotic depletion potential). The individual values named below show the changes in detail (cf. Figure 4): through the slight changes in material mix, the material resources demand also changes for the production phase of the S 400 HYBRID.

6 562 Klaus Ruhland et al. Fig. 4: Comparison of selected material and energy sources [unit/car] For example, the bauxite demand is higher because of the use of more aluminium, as is the iron ore consumption. The lower energy resources demand (natural gas and crude oil) is above all due to the significantly reduced fuel consumption in vehicle operation. Compared to the reference vehicle, 17 per cent of primary energy is saved over the total life cycle. The reduction in primary energy demand of 231 GJ is equivalent to the energy content of around 7000 litres of petrol. 4 Recycling concept of the S 400 HYBRID The method for calculating the recyclability of cars is laid down in the ISO standard and is divided into the following four steps: 1) Pre-treatment (removal of fluids, tyres, the battery and catalytic converters) 2) Dismantling (removal of reuse parts or components for material recycling) 3) Separation of metals in the shredder process 4) Treatment of non-metallic residual fraction (shredder light fraction, SLF) The recycling concept for the S-Class HYBRID was designed in parallel with the vehicle development process, including analysis of the individual components and materials for each stage of the process. On the basis of the quantitative flows stipulated for each step, the recyclability and recoverability rate for the overall vehicle is determined. The deployment for the first time of a lithium ion battery in

7 LCM in the Mobility Sector 563 a hybrid series model has presented new challenges in the area of disposal and recycling as well. Working together with the suppliers and waste disposal partners, an innovative recycling concept has been developed which makes it possible to recover valuable content materials. Fig. 5: Recycling concept of the S 400 HYBRID To improve recycling, numerous components are dismantled -either for direct sale as used replacement parts or for material recycling with economically worthwhile methods. These include aluminium and copper components as well as certain large plastic parts. All plastic components are marked in accordance with the international nomenclature. During the subsequent shredder process for the remaining body shell, the metals are separated for recycling in raw materials production processes. The remaining, mainly organic fraction is separated into different categories and reprocessed into raw materials or energy in an environmentally sound manner. All in all, with the process chain described and in accordance with the ISO calculation model, a recyclability rate of 85 per cent and a recoverability rate of 95 per cent has been established for the S 400 HYBRID within the framework of the approval for the vehicle model. 5 Avoidance of potentially hazardous materials The avoidance of hazardous materials is the top priority during the development, production, operation and recycling of our vehicles. Since as early as 1996, for the protection of both humans and the environment, our in-house standard DBL 8585

8 564 Klaus Ruhland et al. has specified those materials and material categories that may not be incorporated into the materials or components used in Mercedes passenger cars. This DBL standard is already available to designers and materials specialists at the pre-development stage, during the selection of materials and the planning of production processes. Heavy metals forbidden by the EU End-of-Life Vehicle Directive are also covered by this standard. Materials used for components in the passenger compartment and boot are subject to additional emissions limits which are also defined in DBL 8585 as well as in component-specific delivery instructions. The continuous reduction of interior emissions is a major aspect of component and materials development for Mercedes-Benz vehicles. 6 Use of secondary raw materials The main focus of the research into the use of recycled materials accompanying vehicle development is on thermoplastics. In contrast to steel and ferrous materials, to which secondary materials are already added at the raw material stage, recycled plastics must be subjected to a separate testing and approval process for the component in question. Fig. 6: Use of recycled materials in the S-Class In the S-Class, a total of 45 components with a total weight of 21.2 kilograms can be made in part from high-quality recycled plastics. The potential application

9 LCM in the Mobility Sector 565 areas for the use of recycled plastics are restricted to non-visible areas of the vehicle and have by now been by and large exhausted. Typical applications include wheel arch linings, cable ducts and undercarriage panels, which are mainly made from polypropylene (see Figure 6). Another objective is to obtain recycled materials from vehicle-related waste streams where possible, thereby creating material cycles. For example, the front wheel arch linings of the S-Class are produced from reprocessed vehicle components: starter battery housings, bumper coverings from the Mercedes-Benz Recycling System, and production waste from cockpit units. 7 Use of renewable raw materials The use of renewable raw materials in vehicle production focuses on interior applications. The natural fibres predominantly used in series production of the S- Class are coconut, cotton and wool fibres in combination with various polymers. In total, 27 components with a combined weight of just under 43 kilograms and made using natural materials are used in the S-Class. An overview of the types of renewable raw materials used and their fields of application are shown in Figure 7. Fig. 7: Use of renewable raw materials in the S-Class The fastening elements on the backrest trim are made directly from the production scrap in the manufacture of the trim part, thereby enabling an internal materials

10 566 Klaus Ruhland et al. circulation process to be realised. The fasteners are produced using an injection moulding process, the first time renewable raw materials have been used in such a way in series production. 8 Conclusion The new Mercedes-Benz S-Class S 400 HYBRID not only meets the highest standards in terms of safety, comfort, responsiveness and design, but also satisfies all current requirements with regard to environmental compatibility. The environmental certificate documents the clear improvements which have been achieved through the implementation of hybrid technology, as compared with the S 350 reference vehicle. Both the process of design for environment and the product information have been certified by independent experts according to internationally recognised standards. Mercedes-Benz was the world s first vehicle brand to possess this demanding certification, which was awarded in 2005 by TÜV Süd. Thus, the S 400 HYBRID sets not only new standards with regard to engineering, innovation and driving enjoyment. S 400 HYBRID owners can also enjoy a vehicle that, relative to other cars in its class, has very good fuel consumption, very low emissions, a comprehensive recycling concept, and uses a high proportion of renewable raw materials and high-quality recycled materials in short, an excellent result in terms of life cycle assessment. References [1] ISO (2006) Environmental Management Life Cycle Assessment Principles and Framework. ISO, Geneva [2] ISO (2006) Environmental Management Life Cycle Assessment Principles and Framework. ISO, Geneva [3] Finkbeiner M, Hoffmann R, Ruhland K, Liebhart D, Stark B (2006) Application of Life Cycle Assessment for the Environmental Certificate of the Mercedes-Benz S-Class. Int J Life Cycle Assess 11: [4] Daimler (2009) Environmental Certificate of the S 400 Hybrid. Daimler AG, Stuttgart -