Electrification of milk collection routes : route-level energy modelling and charging-time feasibility for battery-electric milk collection

Sammanfattning

The technical feasibility of electrifying milk collection routes using a battery-electric heavy-duty truck was evaluated by combining reconstructed route data with a physics-based, segment-wise energy model and a time-constrained DC fast-charging model. Event-based trip logs from a Swedish milk haulier were reconstructed into continuous routes using digital maps and elevation data, and each route was discretised into short segments. For each segment, battery energy demand was calculated from rolling resistance, aerodynamic drag, road gradient, kinetic energy changes and auxiliary loads. A time-varying vehicle mass was estimated using a loading model based on farm-level cow numbers, assumed milk yield and pumping capacity. A representative long-range battery-electric truck configuration was assumed with 780 kWh nominal battery capacity and a 10–90% operational state-of-charge (SoC) window. DC fast charging was modelled using a piecewise power–SoC curve and applied at candidate locations with assumed maximum charging powers of 400 kW at depots/dairies (Class 1) and 150 kW at farms (Class 2). Three representative milk collection routes were analysed. One route was found to be technically feasible within the SoC constraint when high-power charging was applied at the haulier’s yard and at the dairy, complemented by opportunistic charging at selected farm stops within available dwell times. For the other two routes, the SoC dropped below the minimum limit before route completion even when charging was allowed at all candidate stops using the full available dwell time; critical points occurred at a Class-2 farm stop for route type 2 and at a non-electrified rest area before the final stretch for route type 3. It is concluded that electrification potential is strongly route-dependent and that, for more energy-demanding milk routes, feasibility is primarily constrained by charging time availability and achievable charging power rather than by battery capacity alone. Under the optimistic charging assumptions applied in this study—particularly for farm-based charging—full electrification of the most demanding routes would likely require substantial grid reinforcement and/or operational changes such as route redesign, additional vehicles or dedicated intermediate charging hubs.