It seems to me that cars waste a lot of energy and don’t take advantage of energy opportunities.
Yes, we’ve got braking and even not pushing as the gas recycling energy into batteries – but what about putting little turbines in the exhaust system to reclaim the pressure of the exhaust rushing out – and while we’re at it, let’s close the exhaust and run it to a condenser (maybe powered by the steam pressure of exhaust over the new turbines in the pipes) and then dump the liquid back into the tank – after all exhaust is the unused vaporized part of the gas, it’s not necessarily exhausted materials – there’s energy to still be wrong.
In addition to the exhaust system turbines, putting a turbine wind resistance collector on the hubcaps and maybe the roof would had some wind energy, enough to offset fuel consumption by the external turbine wind resistance.
Then there’s all the surface area, wasted in paint that could be solar heat collectors – to put energy into the battery.
Combustion engines are poor by design, so we need to boost the efficiency of the engines and use multiple energy sources that the vehicle is currently wasting or not talking full advantage of.
Perhaps even something inside to collect and draw off the heat in a parked car and keep the inside cool – something like a car heat pump to provide cool air inside and stop the senseless deaths of pets, babies and small children.