Grid Infrastructure
The charging infrastructure needed for all HGVs in Scotland will require at least 1.3TWh of electrical power.
Substation Strengthening
The research has innovated a methodology for exploring where the energy system will need strengthening to support a switch to BEVs.
The primary substation closest to each proposed charging location was identified. Its ability to support the charging demands resulting from 2% of journeys switching to BEV was assessed using data from Distribution Network Operators (DNOs) unutilised grid capacity.
The highest electrical draw scenario for the sample dataset —mixed depot and en-route charging using 500kW equipment—was selected for analysis. Two further scenarios were considered: a high-intensity scenario with trucks arriving for charging in two concentrated peak periods, and a low-intensity scenario with arrivals spread across four periods. The expected total power draw at each primary substation was calculated and compared to its forecasted headroom. Substations are colour-coded in Figure 11:
- Green: Sufficient headroom even in the high-intensity scenario (80% of substations).
- Amber: Sufficient headroom only in the low-intensity scenario, potentially requiring strengthening (2% of substations).
- Red: Insufficient headroom even in the low-intensity scenario. Strengthening required (18% of substations).
Even with a single digit sample of HGV journeys running with BEV technology, 11 substations require upgrade: Gartsherrie, Glendinning Terrace (Galashiels), Larbert, St. Ninians, Bridge of Don, Burghmuir, Dalwhinnie, Lochdonhead, Milnathort, and Mount Pleasant.

Further Work
Further work using the methodology is required alongside deeper engagement with energy stakeholders. The Agent-Based Model approach enables the findings from the sample to be scaled to the entire HGV fleet while ensuring a wide range of interacting factors are considered. The result will be a robust approach to guiding investment decisions.