Is sustainability measurable?

The term "sustainability" is one of the buzzwords of the 21st century and is finding its way into more and more areas and industries - including the transport sector: sustainable mobility is becoming increasingly popular. But how can one assess whether a planned mobility project is really sustainable? And is it even possible to compare different project alternatives with each other? Andre Noack addressed these questions in his bachelor's thesis in collaboration with the mobility specialization field and the automotive cluster at Bayern Innovativ. In an interview, we talked to him about his project work and analytical approaches.

Mr. Noack, how can I recognize the sustainability of a transport project?

Andre Noack: Measuring the degree to which a transport project is sustainable is difficult. This is because it must first be defined which goals sustainable mobility has in the first place. This can be done through a meta-analysis of existing literature or by surveying the stakeholders of the project. Here, the three dimensions of sustainability - economic, ecological and social - must be considered. It must then be determined whether the projects achieve the goals from the various dimensions. Between the objectives, however, the results cannot be fully compared because they do not share the same unit. For example, the economic aspects are expressed in a currency such as dollars or euros. However, there is no universal unit for social and environmental aspects. Thus, a tool is needed that allows the comparison of goals with different units of all three dimensions.

You chose the utility value analysis because it makes the three dimensions - economic, ecological and social - comparable?

Andre Noack: In the utility value analysis, a point scale is formed with a highly aggregated characteristic value for each goal to be reviewed. This means that for each project alternative is examined how successfully it achieves the previously determined goals of sustainable mobility. In the end, points are assigned for each objective so that one can determine at a glance which project achieves the most points and is therefore the most effective. By awarding points, the problem of unequal units is circumvented.

Are there further strengths of the utility value analysis?

Andre Noack: Compared to other evaluation methods, the utility value analysis has further advantages: it is not subjective, since it is not based on opinions of individual persons. Furthermore, it represents a proven evaluation method in sustainability controlling and in the transport sector. It measures the effectiveness of projects and makes it possible to analyze qualitative and non-monetizable goals and to compare them in a multidimensional goal system by aggregation. Last but not least, utility analysis provides a concrete figure at the end that can be compared with the results of other projects and enables rational decisions.

Are there also weaknesses?

Andre Noack: Like almost everywhere, there are strengths and weaknesses in this tool. A major drawback is that the evaluation of qualitative goals, such as road safety, is abstract and laborious. In addition, utility analysis relies on a broad and accurate database to allow for fair scoring of objectives. Moreover, it only measures the effectiveness of projects, not their efficiency.

One major problem in the acceptance of transportation projects is often the relationship between tax revenues used and the added value achieved for the general public. Does benefit analysis offer a solution here?

Andre Noack: A cost-benefit analysis would have to be carried out to measure efficiency, but this would require the monetization of qualitative goals such as traffic safety. Sustainability goals are often qualitative goals and in some cases can only be monetized with great difficulty or inadequately, as there is often no market price for them. In the transport sector, noise is a case in point. There is no generally accepted scale that can monetize, for example, a noise level of 50 decibels or 70 decibels. The implementation of cost-benefit analysis reaches its limits here.