Can Electricity Replace Gasoline?

Many people are concerned that we will not be able to produce enough electricity to power a rapidly growing fleet of electric vehicles. In 2019, the United States burned 146 billion gallons of gasoline, and it is hard to imagine all that energy being delivered by our electrical grids instead. The skepticism is entirely understandable, but energy experts believe that it is unwarranted.

The U.S. Department of Energy took a close look at how fast we would have to increase the electricity supply to keep pace with EV adoption. Their Grid Integration Technical Team and Integrated Systems Analysis Technical Team published a report in November of 2019 titled, “Summary Report on EVs at Scale and the U.S. Power System”. The researchers examined other periods in U.S. history when electricity demand grew quickly, noting that we have always been able to generate an adequate supply. They do not believe that EV adoption would pose a substantially greater challenge, even if we were to transition to EVs quickly. In their Executive Summary, the researchers write, “The overall conclusion the analysis in this report demonstrates is that, based on historical growth rates, sufficient energy generation and generation capacity is expected to be available to support a growing EV fleet as it evolves over time, even with high market EV growth.”

The technical teams looked at three different adoption scenarios for slow, medium, and fast rates of EV market penetration. Assuming the fastest rate, the proportion of EVs in the national fleet mix would not reach 95% until 2050. Under this scenario, we would have to generate an additional 26 terawatt hours of electricity each year to fuel the growing fleet of EVs. The analysis suggests that incremental increases of this magnitude are entirely feasible. Recently, we have only had to increase the electricity supply by 5 terawatt hours each year, but over the last twenty years the average annual increase was 30 terawatt hours. There were periods when we sustained annual increases of 100 terawatt hours, enough to roll out 25 million new EVs, 50% more than all the light duty vehicles currently being sold each year.

The researchers recognize that there are other obstacles to the electrification of transportation related to distribution, inadequate supply during unusual periods of peak demand, and additional demand from electrified heavy-duty vehicles. But they remain optimistic, writing that these issues “do not undermine the overarching conclusion that EVs at Scale will not pose significantly greater challenges than past evolutions of the U.S. electric power system.”

In order to maximize the significant environmental benefits of EVs, we will need to decarbonize our grids at the same time that we are increasing the supply of electricity, and this will surely be challenging. But these critical industrial transformations will occur gradually over a period of roughly three decades. Judging from past experience, we should be able to deliver a sufficient supply of clean electricity to modernize our national fleet by midcentury.