Electric Vehicles: Impacts on New Zealand’s Electricity System

Abstract

Electric vehicles (EVs) have emerged as genuine contenders as high-energy efficiency, low emissions alternatives to conventional internal combustion vehicles, which have totally dominated road transport for the last century. In the longer term they will compete with such technologies as biofuels, hydrogen and fuel cells in the diversification away from oil fuels and the continuing objective of reducing environmental impacts, in particular the reduction of carbon dioxide emissions from the transport sector, to date a largely intractable problem in the drive to reduce greenhouse gas emissions. Compared to the other alternative transport fuels options, electricity already has an established supply system in New Zealand with a fully integrated system of generation, transmission and distribution. Supplying electricity to vehicles will place additional demands on each of these components but not necessarily in proportion to the additional energy consumed, particularly as much of the electric vehicle battery charging can be undertaken during periods of relatively low electricity demand and battery charging is potentially a controllable load. The objective of this study is to investigate the impacts of electric vehicles on electricity supply and identify when these impacts might become significant. CAENZ has a long-running interest in the supply of energy to the New Zealand economy and the development and resilience of the countyʼs infrastructure. Electric vehicles will impact on both these interests. As yet no independent study of the supply-side issues relating to electric vehicles has been made public. This report is a first step in providing this information and, as such, is not intended to promote electric vehicles but rather to provide some substance to the debate regarding future transport fuels options. The paucity of public information is partly due to the small number of electric vehicles in operation today and their anticipated slow uptake as they gradually become economically competitive with conventional vehicles. It is commonly held that electricity supply will not be a constraint to the use of electric vehicles in that the gradual uptake of electric vehicles over the next ten years at least will allow the electricity supply industry to adapt in turn. This report does not dispute this view but sets out to identify where this adaptation will take place and what issues and opportunities will arise during the process. It does not address the comparative economics of operating electric and conventional vehicles but uses different electric vehicle uptake scenarios based on other studies to place electricity demand from transport into the context of the otherwise expanding electricity market.