Absolute sustainability: Challenges to life cycle engineering

The global society faces huge challenges to meet the expanding needs of a growing population within the constraints posed by a climate crisis and a strongly accelerated loss of biodiversity. For sustainability, the total environmental impact of our activities must respect the planetary boundaries that define what is a safe operating space for our civilization. Engineering must change the current focus on eco-efficiency to a search for solutions that are effective in terms of operating within the share of the total pollution space that they can claim. Engineering for environmental sustainability must be life cycle engineering, and the paper positions it relative to the constraints given by the boundaries of the ecosystems, the targets of the United Nations’ sustainable development goals and the strategies for a circular economy. This top-down perspective is combined with a bottom-up perspective from the life cycle of the product and technology. For each stage of the life cycle, the contents of the toolbox for life cycle engineering are reviewed, and a perspective is given on how absolute environmental sustainability requirements can be incorporated in a target-driven life cycle engineering.