A large oil/gas/coal burning plant is more efficient than thousands of engines burning petrol/diesel, so just converting a large proportion of the fleet with BEVs nudges us a little bit in the right direction. Further, as the grid becomes greener (which it is, in most places in the world), the transport sector automatically gets greener in large fell swoops, without needing to replace thousands of cars. Plus the power generation plants can be placed far from large residential areas, mitigating the health effects on people.
Yes, but it is NOT more efficient than generating all that power, transmitting it, and then putting it into a battery, and reconverting it into mechanical energy again. End-to-end it is LESS efficient.
A tank of gas does not lose energy in transmission nor in storage, and it is far far more weight:performance efficient.
Using oil to generate oil is very very rare. It really only happens on small islands where some other power plant doesn’t make sense and there is no connection to a larger grid. For example, many places in Hawaii used oil before solar became cheap enough. Alaska would have also, if it weren’t for abundant hydro that villages and towns off the grid have always been able to tap into.
Most EV's are charged from a grid that's still burning oil/gas/coal to power them. We haven't achieved much of anything in those areas.
The batteries simply DO NOT EXIST to enable a grid that is based off of renewables - or even half off renewables.