Resource Efficiency and Climate Technologies- Projects 2022

Many industries, including the aviation industry, are turning to carbon fiber-reinforced plastics (CFRP) to an ever greater extent. However, the advantages of these composites, like their low weight, come with disadvantages such as high manufacturing costs and limited recyclability. Until now, the costly components have mostly been disposed of as landfill or incinerated. New technologies and product ideas for fiber composite materials are now paving the way for economically viable reuse. These have been developed as part of the EU project “FiberEUse”. The project has involved 20 partners from seven countries, including the Fraunhofer Institute for Machine Tools and Forming Technology IWU.

One of the developments is a reusable platform for electric vehicles. The individual parts are designed to be usable for up to another 30 years after a car’s first service life. This applies not only to the vehicle frame, but also to the associated seating structure. The platform consists of extruded elements containing carbon fiber-reinforced plastic — these significantly improve the vehicle’s rigidity and protect the batteries from the impacts of any accidents. The longer period of use makes up for the high production costs.

To ensure that the platform and seating structure are durable, recyclable products, large yet simple profiles and nodal elements were combined with complex geometry. Technologies such as pultrusion, presses and detachable joining technologies are used in the production process. In most cases, fiber-reinforced plastics are adhesively bonded, so it is advisable to add thermally expandable particles to the adhesive for subsequent separation. After separation, the adhesive residues can be removed by a laser or by milling, for example, and the components can be bonded again.

The experts at Fraunhofer IWU firmly believe that the circular economy approach will generate new business models, especially in the automotive sector. They are developing new value creation cycles and business scenarios that will enable them to manufacture new products from recyclates.

Project information "FiberUse"

Electric bikes are all the rage. But when a bicycle motor malfunctions, conventional repair methods have limitations — for technical and economic reasons. Consequently, the majority of faulty motors are replaced as a whole. Remanufacturing is a resource-saving alternative. As part of the “Resource Efficient Circular Economy — Innovative Product Cycles (ReziProK)” grant initiative of the German Federal Ministry of Education and Research (BMBF), the “AddRE-Mo” project demonstrated the technical feasibility of remanufacturing electric bicycle motors using 3D printing (additive manufacturing).

To this end, a consortium led by the Fraunhofer Institute for Manufacturing Engineering and Automation IPA analyzed the process chain: A visual classification of the motor variant in question was undertaken with the aid of a neural network, followed by descriptions of suitable disassembly methods that were as non-destructive as possible. In addition to selecting suitable cleaning approaches, the reusability or potential remanufacturing of individual components was also assessed and, finally, the technical feasibility of remanufacturing electric bicycle motors was demonstrated by way of reassembly. 

Additive manufacturing technologies are a key element of the circular economy, particularly when it comes to the gears or torque supports installed in the motor. This led the partners to analyze suitable additive manufacturing processes and materials, and ultimately to produce gears with different geometries using additive manufacturing processes. In addition to service life, other characteristics such as noise generation and temperature resistance were investigated in various load cycles in a specially developed test rig. Finally, field tests under real-world conditions proved the technical feasibility and sustainability of remanufacturing using 3D printed parts. 

Besides Fraunhofer IPA, the project partners involved in “AddRE-Mo” were: Electric Bike Solutions GmbH, cirp GmbH, Trägerverein Umwelttechnologie-Cluster Bayern e. V. and the Wuppertal Institute for Climate, Environment and Energy

Presseinformation »Ersatzteile für Elektrofahrräder aus dem 3D-Drucker«

Geothermal energy has enormous potential to help in the fight against climate change. The water, which can reach temperatures of up to 200 degrees Celsius and be found at depths of up to 5,000 meters, is pumped above ground via boreholes, where it is used for purposes such as driving steam turbines to generate electricity or heating buildings using heat pump systems. Then the cooled water flows back into the earth's crust via a second well, where it is heated up again in the hot rock.

However, drilling these boreholes is expensive and success is not guaranteed, as the exploration risk — i.e., the risk of not finding hot water — is high. The patent-pending Micro Turbine Drilling (MTD^®) technology is intended to increase the chances of success during drilling and improve flow rates. The approach: The mini drill goes down the boreholes and drills out into the surrounding earth to depths of multiple meters. This pushes into the surrounding cracks and fissures and opens them up for hot water extraction. The key component of the MTD^® is a micro boring turbine with a diameter of 36 millimeters and a length of 100 millimeters. The drill bit consists of a tungsten carbide matrix with diamond punches. It can grind through crystalline rock like granite at a rate of 80,000 revolutions per minute; it can also cut through the steel that is used for lining boreholes. Thanks to its deflection saddle, the turbine can drill out from the main bore at an angle of around 45 degrees. The drilling tool uses this to open up new cracks and fissures with hot water around the main well. The MTD^® was developed at the Fraunhofer Research Institution for Energy Infrastructures and Geothermal Systems IEG and at the Fraunhofer-Chalmers Research Centre for Industrial Mathematics FCC. The procedure has already gone through successful testing near the Gotthard Tunnel, at the Bedretto Underground Laboratory for Geosciences and Geoenergies in Switzerland. In 2022, the micro boring turbine won a Red Dot Award in the industry devices category.

Project information "AddRE-Mo"

If the circular economy is to succeed, sustainable production, sustainable consumption and closed-loop economic cycles must be implemented in practice. This will require both technical and system-level solutions. In addition, existing initiatives should be combined so that they can benefit from each others’ expertise rather than starting from scratch every time. This is why the Fraunhofer-Gesellschaft has taken the network of smaller projects that Fraunhofer institutes are involved in across Germany and started combining them to formCIRCONOMY^® Hubs. In this way, it is creating a collective data, knowledge and learning platform that all members of the hubs can access and benefit from. Fraunhofer’s transfer- oriented collaboration activities under the CIRCONOMY^® brand stem from its voluntary commitment to contribute to the United Nation’s Sustainable Development Goals (SDGs).

A number of Fraunhofer institutes have come together to create a charter for Sovereign Value Cycles (SVC), which represents a form of statute for all initiatives cooperating in the CIRCONOMY^® Hubs. The charter is based on three strategies for future sustainable production and consumption models: the systematic implementation of circular processes, the creation of sustainable values and the necessity of sovereignty in value creation. The latter strategy will be realized primarily by involving stakeholders from civil society. The first hub, which has already been established, is focusing on circular carbon technology. The members of the hub are working on combining energy and raw material processes, for example, in order to tap into non-fossil carbon sources, to capture carbon or bring it into a circular system and to integrate these technologies into circular energy and economic systems. They will also develop demonstrators for circular carbon technologies (CCT) in local application centers that will be operated in conjunction with industry partners. At the end of 2022, a second CIRCONOMY® Hub was launched, with a focus on establishing a circular economy for construction materials.

CIRCONOMY^® Hub- project website