Used tyres and waste oil have been used as alternative fuels in cement production for a long time. The most commonly used alternative fuel is plastic, often mixed with production waste from paper, cardboard or textiles. Biomass is also becoming increasingly interesting. This includes, for example, meat and bone meal, which has been used across Europe since the BSE crisis. In addition, we use wood and, to an increasing degree, sewage sludge, nutshells and rice husks, as well as other locally available materials, for energy.