Where are you getting 0.003 terawatts? Another user elsewhere in the thread[0] claimed "Global total energy (not just electricity) consumption is currently 180,000TWh/year, or about 20TW."
Google is showing me other figures like 25,000 terawatt hours of electricity consumption annually.
One might also be careful to count energy properly. The fossil fuel industry has been counting "total energy" including losses to make fossil look bigger and harder to replace. But a gas car throws away like 70% of the energy, so going electric, you don't need the same energy to run the car. Not even close.
Google is showing me other figures like 25,000 terawatt hours of electricity consumption annually.
[0] - https://news.ycombinator.com/item?id=43234856