Reaching this goal would enable all new cars, buses, and trucks to be electric and it allows solar and wind power to provide around half of the energy supply.
IEA (International Energy Agency) have projections of these kinds of goals in 2070-2080.
The Bloomberg New Energy Fund is far more optimistic than the IEA. In 2018, the BloombergNEF Vehicle Outlook for 2030 was for sales of electric cars to be 28% and 84% of electric buses of annual new vehicle sales. The Tesla Battery Future would be to reach 2030 electric vehicle share of new vehicle sales at 100% cars, 80% trucks, and 100%.
Getting 100% of new car sales is only the beginning as there is about 20 years' worth of cars on the world's roads.
If electric vehicles end up having a far lower operating cost that improves too much that they replace the internal combustion engine (ICE) vehicles. The number of electric vehicle sales could go to 200% of annual ICE vehicle sales if the economic benefits encourage a more rapid replacement of older vehicles. The reduction of vehicle miles driven (usage) of the non-electric vehicles would determine how much CO2 emissions are reduced. It will also matter how clean the energy is that we use to charge up the global fleet of electric vehicles. If electric cars are still charged with coal and natural gas power then the cars would only be about 70-80% of the CO2 level of gasoline cars.