1 Introduction
Transport is accounting for a quarter of global greenhouse gas emissions with road
transport being responsible for three thirds of this share. Towards increasing the
environmental sustainability of the transport sector, use phase energy demands
gained significant importance in the development of mass-produced vehicles. This
is induced by legal requirements targeting greenhouse gas emissions for manufacturers’ vehicle fleets. Several measures enable to improve the use phase efficiency, i.e. drivetrain adaptions or optimised aerodynamics. Introducing lightweight
structures reduces energy demands during driving situations with frequent acceleration and deceleration as well as elevations. There are different strategies to
achieve lightweight design. The predominant approach in vehicle engineering is
material substitution. For instance, the application of high strength steels is widespread in the current vehicle generation. As those designs reach their limits in
achieving further weight reductions, new approaches take the stage. While
multi-material designs assign different materials to each component, hybrid designs
combine different materials on a component level.
The integrated framework by Hauschild et al. is presented (see Fig. 1) in order to
provide a perspective on the overall effect of lightweight structures regarding sustainability goals as well as the role of life cycle engineering (LCE) in this context [1].
Within the framework an environmental impact axis and a temporal axis span spaces
of different scopes. Those scopes set a frame for separate optimisation with spatial/
geographical, organisational and technological implications. It is linked to the IPAT
thinking that relates central driving forces to the production and consumption patterns in a future sustainable society. The total environmental impact is presented
(I) as a function of the human population (P), the human affluence (A) and the
technology factor (T). While this represents a top-down approach within the above
mentioned framework that is strongly interrelated with absolute sustainability limits,
the publication on hand focuses on a complementary bottom-up approach. Here,
product development plays a central role as a large share of the later environmental
impact is already decided at this stage. Methods and tools should help to support
decision making towards the upper scopes of concern, orienting it towards absolute
sustainability. Within the framework, LCE is defined as sustainability-oriented
product development activities within the scope of one to several product life cycles.
The methods and tools used in LCE must support reducing the total environmental
impact associated with technology change. Life cycle management (LCM) has to
support this understanding on a company level [2]. As LCE activities relate to an
integrated product and process life cycle planning, the interface between LCM and
LCE is explained as a floating transition zone [3].
The overarching goal of the presented research is the understanding and adaption
of engineering processes in conceptual design towards eco-efficient lightweight
structures. The term eco-efficiency in general is defined according to [4] as environmental impact per unit of product. The current research is focusing on a rather
technological perspective of that definition. Findings from executing development
182
A. Kaluza et al.
Transport is accounting for a quarter of global greenhouse gas emissions with road
transport being responsible for three thirds of this share. Towards increasing the
environmental sustainability of the transport sector, use phase energy demands
gained significant importance in the development of mass-produced vehicles. This
is induced by legal requirements targeting greenhouse gas emissions for manufacturers’ vehicle fleets. Several measures enable to improve the use phase efficiency, i.e. drivetrain adaptions or optimised aerodynamics. Introducing lightweight
structures reduces energy demands during driving situations with frequent acceleration and deceleration as well as elevations. There are different strategies to
achieve lightweight design. The predominant approach in vehicle engineering is
material substitution. For instance, the application of high strength steels is widespread in the current vehicle generation. As those designs reach their limits in
achieving further weight reductions, new approaches take the stage. While
multi-material designs assign different materials to each component, hybrid designs
combine different materials on a component level.
The integrated framework by Hauschild et al. is presented (see Fig. 1) in order to
provide a perspective on the overall effect of lightweight structures regarding sustainability goals as well as the role of life cycle engineering (LCE) in this context [1].
Within the framework an environmental impact axis and a temporal axis span spaces
of different scopes. Those scopes set a frame for separate optimisation with spatial/
geographical, organisational and technological implications. It is linked to the IPAT
thinking that relates central driving forces to the production and consumption patterns in a future sustainable society. The total environmental impact is presented
(I) as a function of the human population (P), the human affluence (A) and the
technology factor (T). While this represents a top-down approach within the above
mentioned framework that is strongly interrelated with absolute sustainability limits,
the publication on hand focuses on a complementary bottom-up approach. Here,
product development plays a central role as a large share of the later environmental
impact is already decided at this stage. Methods and tools should help to support
decision making towards the upper scopes of concern, orienting it towards absolute
sustainability. Within the framework, LCE is defined as sustainability-oriented
product development activities within the scope of one to several product life cycles.
The methods and tools used in LCE must support reducing the total environmental
impact associated with technology change. Life cycle management (LCM) has to
support this understanding on a company level [2]. As LCE activities relate to an
integrated product and process life cycle planning, the interface between LCM and
LCE is explained as a floating transition zone [3].
The overarching goal of the presented research is the understanding and adaption
of engineering processes in conceptual design towards eco-efficient lightweight
structures. The term eco-efficiency in general is defined according to [4] as environmental impact per unit of product. The current research is focusing on a rather
technological perspective of that definition. Findings from executing development
182
A. Kaluza et al.