A paper presented at City Logistics 2025 (Winkelmann, Nandakumar, Spruijtenburg, de Bok — TNO and TU Delft) puts a number on something many city logistics practitioners have suspected but rarely quantified: zero-emission zones (ZEZs) can improve air quality in the city center while quietly shifting the burden onto poorer neighborhoods nearby.
The Netherlands has committed to introducing ZEZs for freight vehicles in 30–40 major cities by 2025, part of the Klimaatakkoord agreement. A common accompanying measure is the urban consolidation center (UCC); a hub at the edge of the zone where diesel trucks hand off goods to electric vans for the final leg.
This study links two existing models to test what that actually does to a city: the agent-based freight simulator MASS-GT (which generates realistic shipment and tour patterns across eight logistics segments, from parcels to construction goods) and the TNO Digital Twin, which assigns those trips to Amsterdam’s real road network and computes traffic, emissions, and air quality indicators.
The team modeled five scenarios for 2035: a no-intervention baseline, plus small and large ZEZs (following the S100 ring road and A10 highway respectively), each tested under low and high assumptions about how much freight would actually route through UCCs versus simply converting to electric vehicles.
The headline result is a genuine trade-off. Zero-emission vehicle kilometers rose to a 9–33% share of total freight travel, and NO2 emissions dropped sharply in the city center (Centrum saw roughly 25–30% reductions). But total trips and vehicle-kilometers both increased overall, because each rerouted journey gets split into two: a combustion-engine leg to the UCC, then an electric leg into the zone. That extra traffic concentrates around the UCC locations themselves. And in the large-ZEZ scenarios, the UCC sited in Amsterdam Nieuw-West actually saw emissions rise by 5–7%.
The equity angle is the sharpest finding. The paper contrasts two real neighborhoods: Slotermeer, near the Nieuw-West UCC, with an average income of about €26,000, saw a marked increase in NO2; Jordaan, a wealthier neighborhood (€45,500 average income) closer to the city center, saw emissions fall substantially. In other words, UCC placement decisions can end up redistributing air pollution from higher- to lower-income areas — precisely the kind of unintended distributional effect that’s easy to miss without spatially granular modeling.
The authors are careful to flag this as exploratory: UCC-use probabilities for the “high consolidation” scenarios are hypothetical, not observed. Their call to action is clear. UCC siting needs to be treated as an equity question, not just a logistics-efficiency one, and participatory planning approaches deserve more attention.