Electric Long Haul (LH) Transport Trucks may feature batteries that are 10 or more times the capacity of passenger electric vehicle (EV) batteries. Charging these enormous Trucks could put a major strain on our electric grid. Conversely, these massive batteries could offer valuable services and put power back onto grid at strategic times and places. A study will examine the potential grid impacts of LHEVs on the Ontario grid. Archetypal long-haul routes of existing transport patterns across Ontario will provide a foundation for the analysis. Critical variables such as state of charge, charging rates, and charging times will be parameterized to assess impacts on the size and shape of electricity demand at a distribution, and wider grid level. Finally, a regionalized case study will examine the potential for LHEVs to function as Distributed Energy Resources (DERs) while serving in Ontario’s rapidly growing, and electrically intensive, Indoor Agricultural sector.