Developing green design guidelines: a formal method and case study

Abstract

This thesis describes and demonstrates a method for consolidating, developing, and using green design guidelines for the innovation of greener products. Life cycle analysis (LCA) is one well-accepted tool for quantifying the environmental impacts of a product so designers can identify areas for redesign effort. However, LCA is a retrospective design tool that requires detailed design information that isn’t known until designs are near completion. Alternatively, green design guidelines provide proven techniques for designing greener products. They can be used during the early stages of design, when many decisions fundamental to innovation and environmental impact are made and before LCA is viable. This thesis extends the work already done in green design guidelines, by updating the current knowledge base and introducing a method for extending the set of existing guidelines to encompass new and emerging areas of sustainability. While guidelines have been created from prior experience in design for environment and life cycle analysis, they have not been maintained as a shared and coordinated repertoire of green design solutions. Instead, sets of guidelines are scattered throughout the literature, contain overlaps, operate at different levels of abstraction, and have varying levels of completeness. For example, some areas of green design guidelines, such as design for disassembly, are well established, while other areas of green design guidelines, such as minimizing energy consumption during use, are still being explored. Additionally, while numerous examples of green design guidelines exist, many of the guidelines have no documented validation of their life cycle impacts. The work for this thesis began with the compilation of a dynamic knowledge base of green design guidelines. This set of guidelines is a consolidation and updating of the green design guidelines already available in literature and can be used as a starting poinrt for future improvements and extensions as the field develops. A standard method was then proposed and tested for creating guidelines in currently undeveloped areas of green design, particularly energy consumption during the operation of a product. The method employs reverse engineering techniques and life cycle analysis to identify green requirements and develop corresponding, new green design guidelines. A case study of electric kettles demonstrated the usefulness of the method by yielding four new guidelines and four, corresponding, energy saving re-designs. For this example, the redesigns showed that guidelines can reduce energy consumption, but may incur tradeoffs with other life cycle stages. Calculation of tradeoffs revealed a range of net life cycle impact values that were caused by increased manufacturing demands and variability in consumer use habits. In addition to redesign in the kettle study, the four new guidelines were tested for usefulness in new product design by use of focus groups. Two groups were tasked with designing a new energy efficient toaster concept. Only one group was given the four green design guidelines that were uncovered using the proposed method. The design group using the new green design guidelines produced more viable and practical green features than the design group that did not have the guidelines as a design tool. These preliminary results suggest that the proposed method is useful for creating new guidelines that are beneficial to design teams tackling novel design problems that differ from the original case study. Further work is needed to establish the statistical significance of these results.