Under the magnifying glass: circular economy and recycling

Reduce, reuse, recycle: That is the annual motto at zdi.NRW. The robot competition, Science Video Award and the zdi heroines October focus on this topic. But what exactly does circular economy mean? What technologies are behind it? And what economic size and importance for the labor market does it have for Germany?

Gold prospecting in the present

From old to new! – This is how one could summarize the objective of today’s circular economy. The circular economy has undergone an enormous change in the last 30 years; from a pure garbage disposal and city cleaning to a complex economic sector with a wide range of services. Waste has a different reputation today. It's no longer just something we throw in a big hole and fill up with dirt. Waste is nowadays the supplier of many valuable raw materials and energy.

Circular economy - what is it?

In short: The circular economy arose from the need for environmentally friendly and resource-saving production processes.

With the beginning of the industrial revolution, a linear economic system prevailed. This meant that the consumption of goods was designed for one-time use. Resources were taken from the earth, goods were manufactured, bought and disposed of. But for several decades it has been clear that resources are finite and our consumer behavior is destroying the world with pollutants and hazardous waste.

Graphic comparison of the linear economy system and the circular economy, © AdobeStock

Our economic system is undergoing a paradigm shift. The production of goods is no longer designed for one-time use, i.e. linearly. Rather, goods should circulate. And in the best case, this economic system will get by without waste (zero waste) and without emissions (zero emissions).

Pioneers of the modern circular economy are the German chemist Michael Braungart and the American architect William McDonough. Together they developed the cradle-to-cradle principle (English, German: from cradle to cradle). Products that are manufactured according to this principle return their biological nutrients to biological cycles and try to keep their technical components in technical cycles continuously.

Examples: from house construction to mobility

Urban Mining

The construction and real estate sector is the most resource-intensive industry of all. They account for about half of the total raw material consumption. Therefore, nowadays the rubble is separated into its components and recycled.


With upcycling, discarded objects are given a new function (e.g. sewing a wallet out of old jeans or using an old jar as a tea light). In the meantime, there are already so-called repair cafés in many cities, where hobby craftsmen repair defective devices.


Resource efficiency is a key pillar of the circular economy. Renewable sources such as wind and solar energy are increasingly becoming an alternative to fossil fuels. But the use of waste heat in production facilities or the production of energy from waste is also becoming more and more popular.


A private car is only used for about 4 percent of its lifespan. Cars offered by sharing services experience about 45 percent of their lifespan.

technologies in the circular economy


Processes at the highest technical level are required for the pre-sorting and recycling of waste. From Blockchain to the Internet of Things, many technologies are represented in the circular economy. Around waste disposal today there are networked rubbish bins or glass collection containers that communicate via radio technology. They tell the disposal company how full the waste containers are and help to optimize the routes of the collection vehicles.

Sort by

Once the rubbish has been collected, a technologically sophisticated sorting technique is important. This is the only way that waste can be recycled or processed into secondary fuels. In the waste collection centers, people are therefore increasingly relying on smart waste separation. Here, adaptive robot systems take over the separation and evaluation of the waste. Also the recycling processes are optimized with the latest technology. The special challenge here is the complex composition of modern products. The better and cleaner a product can be broken down into its individual parts, the more efficiently the individual components can be recycled. Digital technologies, for example, which display and record the individual product life cycles, help here. Companies can then plan recycling processes during product development.


More and more methods are being developed to generate energy from waste. Incidentally, the first incinerators already existed at the end of the 19th century. Modern incinerators reduce the initial volume of waste by up to 95%. The resulting energy can be used in part as electricity. And now the heat generated when burning can also be used for heating. To the energy there are also biochemical processes. In the production of biogas, organic waste is fermented with the help of bacteria. Another approach is to harvest energy directly from organic matter using decomposing enzymes. One could imagine a potato battery here. Dozens of other approaches to produce something that can be used to generate energy from waste are currently being tested.

Source: Status report of the German circular economy BDE-BDSV-bvse-ITAD-PlasticEurope Deutschland eV-VDM-VDMA-VHI-VKU 2018

Economic importance in Germany and NRW*

In 2020, more than 310.000 people were involved in the circular economy in almost 11.000 municipal and private companies. They generated sales of around 85 billion euros.
With 75.000 employees in this sector and a turnover of 27,3 billion euros, North Rhine-Westphalia is the largest location in Germany. The circular economy has developed into a real engine of growth here. In addition, 19 percent of all nationwide patents come from NRW.

This makes the circular economy one of the most important economic sectors in the German environmental economy. But it is also a major player in international trade, particularly in plant, machinery and secondary raw materials. In many countries of the world there is a high demand for technologies and solutions for waste disposal. The market segment "technology for waste management" alone had an export volume of 2018 billion euros in 5,1.

* The figures are taken from the Environmental Economy Report NRW 2017 and the Circular Economy Status Report 2020.

Circular economy at zdi

zdi is always oriented towards the latest technological and socially relevant topics. In this way, we can specifically contribute to the promotion of young MINT specialists.

This year, for example, the zdi robot competition under the motto "Reuse - Reduce - Recycle". This year, 170 student teams from all over NRW will compete against each other with their self-programmed robots.
In addition to its environmental relevance, the topic also has a pedagogical advantage; Connections between scientific, ecological and economic challenges could be communicated in an interesting and understandable way.

In addition, some zdi networks and zdi student laboratories have specialized in this topic with their range of courses and experiments.
Two zdi student laboratories are particularly worth mentioning at this point:

  • The zdi-MINTlab - laboratory for schoolchildren in Minden-Lübbecke recently opened the Smart Recycling Factory. Focal points include creative gardening in the city, innovative 3D printing, robotics and sensors in waste disposal, renewable energies or the programming of a smart recycling robot.
  • The  zdi school laboratory MINT-Lab is active on the premises of the Leppe disposal center. As part of the :metabolon project, it offers all age groups a learning-specific experience space for the topics of environment, resources and forms of energy of the future. A special focus is on the promotion of young STEM students.

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