Sustainability Assessment Unit

Institute-wide central contact point for ecological and economic technology assessment

New technologies are often presented as cure-all solutions – be it in the socio-economic field or from the perspective of ecological sustainability.

However, due to their novel, fast-growing and uncertain nature, new technologies can also lead to increased resource consumption, offsetting all the benefits.

INATECH established the Sustainability Assessment Unit to tackle this issue. It brings expertise on and methods for sustainability assessment under one roof.

The unit is funded by the Eva Mayr-Stihl Foundation.


The Sustainability Assessment Unit combines competencies and thus makes it possible for all professorships to evaluate their research projects comprehensively. The focus is on the following areas:


Methods used

The focus is on the following methods:

Life-cycle analysis (LCA)

Ecological assessment is a systematic analysis of the ecological footprint left by products and services over their entire life cycle.

In accordance with the cause-and-effect principle, the resources used (materials and energy) and emissions generated (air, water, earth) are allocated to the product from raw-material extraction, through production, distribution and use, and finally to disposal.

Life-cycle costing(LCC)

Life-cycle costing analyzes the costs of a product or service over its entire life cycle. Life-cycle costing is used as a method for planning, evaluating and comparing investment alternatives as well as for profitability analysis of systems and products.

Material-flow analysis (MFA)

Material-flow analysis balances material and energy flows within and beyond a system’s boundaries. A system could be a service, process, industry, or an economy. Material-flow analysis analyses supply chains, with particular attention given to resource efficiency.

Case study: “Recycling bottle caps in sandwich structures”

This case study shows the application of industrial-ecology methods in the context of a doctoral thesis at INATECH.

P. Oliveira, S. Kilchert, M. May, T.H. Panzera, F. Scarpa, S. Hiermaier: »Life cycle analysis of upcycled bottle caps as sustainable honeycomb-core«, Environmental Management, in review.

  • Challenge

    The recycling and efficient use of materials and natural resources is an essential component of resource-conserving recycling management. The extent to which a technical approach delivers advantages in this respect is, however, often difficult to assess. Recycling not only leads to more resource-efficient use, it also alters a material’s mechanical properties. This often results in a different application of the material in question. To determine under which conditions a technical approach is advantageous for ecological performance, we have to combine engineering-science and industrial-ecology perspectives.

  • Method

    The mechanical properties of various recycled materials and structures representing different options for the components of a sandwich structure were characterized experimentally from an engineering-science perspective. The environmental impact associated with the material and structure options was then evaluated using life-cycle assessment from an industrial-ecology perspective. Examples investigated include:

    – Recycled bottle caps from different production sites as sandwich core
    – Top layers of flax laminate, recycled PET and aluminum
    – Epoxy and bio-based polymer adhesives

  • Results

    Using the observed strengths and weaknesses of the different material and structural options, we were able to identify the combinations of sandwich components that effect a favorable balance between mechanical and environmental performance.

    The objective of the present analysis was to minimize the weight and ecological footprint of the sandwich structure while increasing its mechanical properties (in this case dynamic-impact load, flexural stiffness and strength). A balance of these aspects is derived from the ratio of environmental indicators, e.g. climate change potential (kg CO2-eq.), to weight-specific mechanical properties, such as flexural modulus or impact strength. Lower ratios indicate a lower specific ecological footprint compared to the mechanical properties.

    On balance, recycling bottle caps in sandwich structures shows promising environmental performance and mechanical properties. The relationship between the mechanical performance of the bottle-cap plate and its life cycle showed up to 71% lower specific emissions with more sustainable components. The sandwich structures studied with the recycled honeycomb core of bottle caps showed up to 14% lower values compared to commercial honeycombs from the literature in terms of climate-change indicators.



You can reach the Sustainability Assessment Unit via the following contact:

Dr. Sebastian Kilchert
Sustainability Assessment Unit

INATECH, Emmy-Noether-Str. 2,
79110 Freiburg, Germany

Tel.: +49 (0)761/203-54248