Keeping carbon in the loop is a short sentence that describes the Carbon2Chem (R) project. Climate protection requires a reduction of CO2 emissions as well as less use of fossil fuels. In the project, a consortium from industry and science works on implementing a flexible carbon capture and utilization (CCU) concept for the carbon-based industry. An example is the cross-industrial network of steel industry, chemical industry, and energy industry. Instead of being harmful waste, top gases from the steel mill now serve as raw material for the production of synthetic fuels, plastics, and basic chemicals. This is possible through the systemic use of renewable energy.