A lot has been discussed about transportation becoming carbon-free by 2035. Standard battery-powered EVs require an average of about 0.3 kilowatt-hour per mile. With 230 million registered drivers in the U.S., driving about 13,500 miles each year means the economy demands about 3 trillion miles/year. If this current need were totally electrified it would require about 1 trillion KWH per year or 1 million gigawatts.
Solar photovoltaic combined with wind power currently generates about 170 gigawatts/year (energy.gov, 2018). We would need to expand these carbon-free footprints by a factor of 6,200 times just to accommodate today’s personal transportation needs.
Another possible avenue would employ nuclear power. The largest operating reactor site (the Kori reactors in South Korea) generates about 5,000 gigawatts/year. Only 200 such reactors would be needed and we already have 94 working today; although many are older designs, not 24/7, less powerful and are used more for home heating/cooling/cooking. Starting from scratch, the next 14 years we will need to bring one reactor online almost every month.
Admittedly, these are aspirational targets and no one knows the future of renewable efficiencies, battery storage or transpiration needs, but the math here just doesn’t seem to work out.