Overview of cost:
The investment costs depend on the surface area of the channel and average 31 € per fattener place (European Commission, 2017). The annual extra costs may be € 2 for fattening pigs, €14 for pregnant or lactating sows and €1 per animal place for weaners. The emission reduction costs for fattening pigs make 4 €, for pregnant sows 16 €, for lactating sows 8 € and for weaners 6-7 € per saved kg NH3 (UN/ECE, 2014). Cleaning the balls require additional labour work (European Commission, 2017).