CONCLUSION - CO2 reduction on industrial composting plants using GNSS-based cooperative localization

Composting of organic waste plays a significant role in climate protection. Nevertheless, climate-damaging greenhouse gases such as carbon dioxide (CO2) or methane (CH4) are produced in the process of composting. The project aims to reduce climate-damaging emissions in commercial composting. The project is based on three pillars to reduce emissions. The first pillar is an innovative concept for GNSS-based cooperative localisation of several electrically driven, autonomous compost turners (e-Wenders), which is being developed and tested in the project. By turning the compost more frequently with climate-friendly e-turners, the generation of climate-damaging greenhouse gases during rotting is to be reduced. To test the concept, machinery at a composting plant is equipped with low-cost GNSS receivers. By combining the measurements of the low-cost receivers with the measurements at a dynamic GNSS reference station (baseline computation via double-differentiated carrier phases), the positions of the working machines are to be determined precisely. A collaborative localisation of machines with GNSS sensors of varying quality and experimental testing in the laboratory is an absolute novelty. The second pillar is the development of a sharing concept for working machines with an innovative system engineering approach. The idea is that several composting plants share autonomous e-Wenders to save resources. The e-Wenders are equipped with GNSS receivers and are transported from distribution centres (hubs) to the respective composting plants. In this way, even small composting plants can compost in an environmentally friendly way and do not have to rely on diesel-powered equipment. The third pillar is the development of an emission model using a coupled Computational Fluid Dynamics (CFD)- Discrete Element Method (DEM) simulation. The aim is to investigate how CO2 and CH4 are released during the compost-turning process. Based on the simulation, it will be investigated which measures could be taken to reduce emissions. By measuring and georeferencing the actual emissions, emission heatmaps can be created and the simulations validated. As a result, the project’s final evaluation of the emission reduction should reveal how many CO2 and CH4 emissions can be saved in composting with the help of the developed approaches.