" Coming to think of it, turbochargers recycle some exhaust energy at the expense of increased backpressure. Also, and correct me if I am wrong, the main reason why the turbochargers are as close as they are to the engine is for their direct coupling into the intake. If the turbines are used instead as electrical generators then the location does not need to be as close to the engine as it is which could reduce the thermal stress quite a bit and remove the need of wastegates. If anything, if the battery is used as a buffer to recycle the exhaust flow energy it makes more sense for them to be in the rear (where the battery is located), from electrical stand point. The recycled energy can be used to power the electrical compressor and increase efficiency overall (less load on the crankshaft coupled generator). Another advantage of the electrical compressor that I can think of is that it is decoupled from the crankshaft which imposes certain limitations to superchargers, generally speaking. The downside – increased weight. Oh well, this is just the 2c of an electrical engineer with a limited knowledge in IC engines.