Sewage sludge consists of organic material up to 70% and is therefore an excellent energy source and raw material for high-quality fertilizers. The G+R Technology Group  manufactures most-modern drying plants for the conversion of sewage sludge into high-quality combustibles. Entirely dried sewage sludge provides as much energy as brown coal – having one decisive advantage: the combustible is CO₂ neutral and environmentally friendly. G+R drying plants are already in operation in many major German sewage treatment plants.