Why are all modern hybrid and plug in hybrid cars paired with gas engines rather than diesel engines? The diesel and hybrid pair seem like a great idea in theory.

Question

A lot of people see hybrids and plug in hybrids as a great middle ground between ICE and EV, so why not make a diesel hybrid. They can be used in a variety of vehicles, and can reduce the nox and particulate emissions diesels are known for. So why isn’t there a modern diesel hybrid being produced, at least as a passenger car?

In: Engineering

Answer 1

there are multiple reasons for this.

first of all diesel engines have a very low RPM range to work with which is something you dont really want.

Beside this Diesel engines have major emissions problems that almost always require the engine and exhaust to be very hot in order for the emissions systems to work and even with that they still need Diesel emission fluid to meet their emissions.

You will also notice that the vast majority of **good** hybrids are not using turbo charged engines as the turbo lag is also something you want to avoid as well as the complexity and reliability problems of turbos which can be entirely avoided by not using them.

Overall the characteristics of a naturally aspirated engine combined with an electric motor are simply the best of both worlds as the electric motor makes up for the low torque and power of the combustion engine at low RPM while the combustion engine itself can output peak power at the upper end where smaller electric motors run out of steam.

And beside all this theres also the fact that diesel engines are more expensive so this would make hybrids even more expensive then they already are.