Impacts of electric vehicle policy on the New Zealand energy system: A retro-analysis

Abstract

Policy in New Zealand supports a transition to Electric Vehicles (EVs), which are projected to comprise 40% of the light vehicle fleet by 2040. The impact of EVs cannot be decoupled from the power generation. Therefore, in this study, New Zealand’s energy system (transport and national power generation) is modelled in LEAP and the impacts of a 40% transition to EVs assessed with a multiple-scenario 2019-based retro-analysis. Two charging scenarios are simulated, modelling “Optimistic” and “Concentrated” charging. Two methods of generation expansion are modelled: “Mixed Renewables” and “Non-Renewables”. Results show existing generation can support a 16% EV transition with Concentrated charging, and a 43% transition with Optimistic charging, without decreasing the reserve margin. It is expected a 40% EV transition with a Non-Renewable power system expansion will reduce energy sector GHG emissions by 2% and costs by 7%, and a Mixed Renewables expansion will reduce emissions by 17%–18% and costs by 4%–5%. These results suggest an EV transition is an effective method for New Zealand to meet GHG emission targets, particularly with renewable generation expansion. Important areas of future research are identified, including: alternative EV charging strategies, peak travel events, embodied vehicle emissions, and the costs of power-system upgrades.