Powering the Future: A Global Analysis of Well-to-Wheel Efficiency in Electric Vehicles

Abstract

Over the past few decades global warming and its effects on the environment has gained a lot of attention. Many studies have determined that keeping the increase in global temperature below 1.5 degrees Celsius is key to avoid irreversible damage to the environment. This is particularly challenging for the auto industry as it relies on fossil fuel combustion as a source of energy to enable transportation. With this goal of keeping rise in global temperatures down, several automotive OEMs have adopted modern technologies like hybrid electric vehicles, plug in hybrid electric vehicles, fuel cell batteries and battery electric vehicles to combat climate change. Among most these technologies, the common theme is to move away from using any direct fossil fuel combustion and rely on electricity from the grid to power propulsion. Although this is beneficial for reducing the number of direct emissions from automotive sector, it can increase the emissions from energy sector because the grid needs to produce more energy to charge these vehicles. However, this additional demand can be met via electricity production from renewable sources or non-renewable sources. Therefore, to get an accurate analysis of the impact of these alternative technologies, it becomes critical to analyze the efficiency, energy consumption and CO2 emissions from the source of energy to the stage where the energy is converted to useful work. This study focuses on the estimation of a well to wheels efficiency of electric vehicles across the globe. Well to wheels efficiency considers the efficiency of all stages of energy consumption that form a part of the lifecycle of the electric vehicles. In addition to computing the well to wheels efficiency, this study also analyses the variation in wells-to-wheels efficiency in various parts of the world. Understanding this regional dependency is vital (and unique to this study) as each region relies on a different composition of sources to generate electricity which results in large variation of well to wheels efficiency across the globe. Computation of well to wheels efficiency is crucial to get a comprehensive estimate of energy consumption and losses at each stage in the lifecycle of electric vehicle’s operation and this can aid in identifying key stages where efficiency can be improved to make the most impact.