Product design and sustainable development in engineering process.

Vargova, Jana ; Badida, Miroslav ; Hricova, Beata 等

1. INTRODUCTION

Traditionally, the design process is seen as one link in a chain of steps. An organisation commissions a new process or product to help it reach its goals. The engineer that accepts the task of delivering the design is given a programme of requirements, which the product should ultimately adhere to. This list of requirements is also used subsequently to evaluate the design that the engineer has produced.

Once the designer has accepted the programme of requirements, the next step is to obtain a solution that fits into all requirements completely (even if the demands seem to be inconsistent). This lack of critique depends on the engineer's culture.

2. THE DESIGN PROCESS

Most engineers concern themselves with physical products in the broadest sense, i.e. every physical system designed with a certain purpose is a product. A bicycle is a product, but so is a factory, a water treatment facility, and a new area of a city. Designing is the developing and planning of such a product.

Different disciplines have different design processes, though they share some common characteristics. The design process can be characterized by the cycle of design, which describes certain steps present in each design process (Fig. 1). When designing for sustainable development, designers should bear it in mind throughout the design process.

The most important decisions concerning sustainable development take place in the initial phase of the design process--analysis; the earlier sustainable development plays a role in the process, the larger its influence. It is much easier to alter the assignment to improve sustainability than trying to increase the sustainability of an already finished detailed design. (Mihok & Liberkova, 2005)

2.1 Analysis

The core of the design process is the function of the product that is to be designed. 'Function' does not only mean the technical function, but also any social, cultural, psychological and economic functions the product will per-form. Although the programme of requirements will contain the main functions, these need to be analysed for further requirements.

Every design process follows from a problem that needs to be solved. It is the designer's job to identify the actual problem, clarify it and express it in a problem statement, i.e. the designer analyses what the real problem is. This often turns out to be a different problem from the one expressed by the commissioner. Only when the problem is defined clearly and in 'do-able' terms can the designer search for the most sustainable way of solving it. (Rusko & Volakova, 2004)

The designer may conclude that major changes need to be made for a sustainable solution. But the commissioner will frequently not allow the designer to bring about such a large change. The programme of requirements is generally so restrictive that only small product improvements are possible. The engineer should therefore review the commissioner's programme of requirements critically before accepting a design assignment.

[FIGURE 1 OMITTED]

3. LIFE-CYCLE ANALYSIS (LCA)

LCA is a tool that allows the total environmental impact of a design or a product to be analysed. It can be used during different phases of the design process. It can also be used to optimise the environmental performance of a design.

LCA quantifies the environmental impact of a certain product-system. The LCA of an existing product or system can set the bottom line for a new design. The product system encompasses all phases of the product life, i.e.

* Raw materials acquisition and refining (e.g. mining, drilling, agriculture, forestry, fisheries)

* Processing and production of product and production equipment

* Distribution and transport

* Use, re-use and maintenance

* End-of-life landfilling, incineration, litter and recycling

In all these phases, the contribution of the product to different forms of pollution (e.g. the greenhouse effect, ozone layer depletion and acidification) is calculated.

However, these different forms of environmental impact cannot be added together. In order to calculate one single number as the result of the LCA, weight factors have to be introduced that set the relative priority for each environmental problem. Weight factors can be derived from the relative distance of the current situation in regard to the goals set out in policy documents. (Muransky & Badida, 2005) Alternative designs and materials can thus be compared. If priorities change, the LCA score will change too.

4. DESIGN TOOLS AND STRATEGIES

There is a large number of strategies that a designer can follow to design eco-efficiently. In the LiDS wheel (Lifecycle Design Strategies), these strategies are clustered and visualised. Each strategy contains a number of basic rules. (Mulder, 2006) Strategy 1: choose materials with low environmental impact Chose materials that are:

* Clean materials. Choose non-toxic and harmless materials. For example, avoid materials containing heavy metals, asbestos, chlorofluorocarbons (CFCs) and endocrine disruptors such as phthalates.

* Renewable materials. Avoid scarce materials, i.e. materials from a non-renewable or slowly renewing sources such as fossil fuels, copper, tin, zinc and platinum. Plastics too are made from fossil fuels and are counted as scarce materials.

Strategy 2: dematerialise

The principles of dematerialisation are:

* Reduction of weight. Using less material often reduces the product's environmental impact. Less material means less resource consumption, less waste and a lower environmental impact during transportation.

* Reduction in volume. When the product and its packaging are reduced in size and volume, more products can be transported in a given transport facility, making transportation more efficient. Another solution is to make the product foldable or 'nest-able'.

Strategy 3: select environmentally efficient production techniques

* Environmentally sound production processes. For example, DSM-Cist in Delft replaced 15 chemical production steps in pharmaceutical production with five bio technological ones. This drastically reduced the consumption of water and harmful emissions.

* Fewer production steps. For example, combining various parts into one cast item can save assembly steps and simplify the design. Chose materials that require no finishing touches or only apply finishing to parts that absolutely require it (e.g. because they are visible).

* Lower/cleaner energy consumption. Make efficient use of (sustainable) energy sources. Use sustainable energy sources such as windmills and solar cells in the production process. Also use waste heat from other companies situated nearby.

Strategy 4: select an environmentally sound distribution system

* Less and cleaner packaging. Use less packaging material or packaging with a lower environmental impact, e.g. replace polystyrene packaging with cardboard. Bioplastics made from starch, for example, can be a good replacement for plastic foams in some applications. A reduction in packaging can also be obtained by designing the product in such a way that there is no need for packaging or less packaging is needed.

* Energy-efficient transport mode. Some modes of transport are more polluting than others. Freight transport by train or boat is preferable to transport by road or plane.

* Energy-efficient logistics. The cleanest transport is no transport. Nowadays, production sites in a supply chain are often far apart. Reducing transport distances can result in significant energy savings.

Strategy 5: reduce environmental impact in the use phase A product also has an environmental impact during the use phase. This should be considered in the design process. The following principles hold:

* Reduce energy consumption during use. For example, energy consumption by a vehicle is generally far greater than the energy consumed in its production.

Strategy 6: optimise the life-span

A product with a long life-span will have a lower environmental impact because fewer materials are used overall. Prolongation of the technical lifespan can be obtained by making:

* The product more reliable and easier to repair.

* Maintenance easier.

Strategy 7: optimise end-of-life system

* Stimulate re-use of the entire product.

* Remanufacturing/refurbishing. Stimulate re-use of parts. But to enable the re-use of parts, it is necessary that the product can be dismantled easily.

* Recycling of materials the less variation in materials used, the more efficiently materials can be recycled.

* Safe incineration. Avoid the use of substances that generate hazardous fumes when incinerated. (Mulder, 2006)

5. CONCLUSION

A company's societal an economical responsibilities are more than just making a profit. The role of companies is to create value by using scarce goods in an effective and efficient manner to produce goods and services. Sustainable entrepreneurship generally implies that corporations are willing and able to behave responsibly towards society and environment.

The paper was elaborated in connection with the projects VEGA No. 1/3232/06, solved at the Technical University in Kosice.

6. REFERENCES

Hauschild, M., Jeswiet, J. & Alting, L.(2004): "Design for the Environment--Do we get the focus right". 2004 Annals of CIRP Vol. 53/1/2004; pp 1-4

Mihok, J.--Liberkova, L.(2005): Vyhodnocovanie efektivnosti znizovania miery zatazenosti ZP. Evaluation of efficiency of environmental load elimination. In: Moderne pristupy k manazmentu podniku, Bratislava, STU, 2005, s. 360-363, ISBN80-227-2284-7

Muransky, J.--Badida, M. (2005): Ekodizajn v strojdrstve. Zdklady metodiky. Ecodesign in Mechanical Engineering. Technicka univerzita v Kosiciach, Vydavatel'stvo Michala Vaska, Presov, 2005, 304 s., ISBN 80-8073-119-5

Mulder, K (2006): Sustainable development for engineers. Greenleaf publishing, Sheffield, UK. 288p. ISBN-10: 874719-19-5.

Rusko, M., Volakova, M.(2004): Prieskum vyuzivania environmentdlneho oznacovania a LCA na Slovensku. Review of utilisation of environmetal labelling and LCA in Slovakia. Environmentalni znaceni 2004/2, Praha, 2004, s. 6-7, ISSN 1212-4761