Port-related emissions are a growing problem for urban areas often located directly next to ports highly frequented by trucks and vessels. Empty truck trips are responsible for a significant share of these emissions. Truck appointment systems (TASs) allow scheduling of truck arrivals and enable collaboration among truckers. Though, TASs leveraging the potential to reduce avoidable emissions due to empty trips have hardly been studied. We aim to show how a TAS following this idea may be designed and evaluate the approach. We thus review requirements for a collaborative TAS and develop a discrete-event simulation model to assess coordinated truck appointments in a practical case of drayage. The results indicate that the approach effectively reduces port-related truck emissions, but might create congestion in the port. The considered case refers to drayage processes, but may also be transferred to the hinterland. The developed simulation model assumes a generic truck appointment process and may also serve to analyze diverse cases.