Charging six cars at once is fine. Charging 60 million might be a bit tougher. Nadya Kubik/Shutterstock.com December 4, 2018 Switching to electric vehicles could save the US billions, but timing is everything F. Todd Davidson, The University of Texas at Austin; Dave Tuttle, The University of Texas at Austin; Joshua D. Rhodes, The University of Texas at Austin, and Kazunori Nagasawa, National Renewable Energy Laboratory Ensuring that everyone doesn’t charge their cars simultaneously will make a big difference.