The Extended Range Electric Vehicle is an electric vehicle system with an additional energy storage and conversion system. A Fuel Cell could be that alternative, but we tend to describe that as a FCEV and keep the EREV or REEV definition as an internal combustion engine based generator.
Advantages and Disadvantages
The advantage of the EREV over the PHEV is that the driveline can be optimised independently of the range extender. The Plugin Hybrid Electric Vehicle (PHEV) is a complex system where the internal combustion engine and electrive drive are both connected to the driveline and have to operate in parallel and independently.
Considerations
- Battery energy and power capability
- energy sized for a given daily range
- power for maximum load and speed
- regen power from braking and range extender
- Generator capability
- sized for average power demand over a cycle
- or power output to meet high load average
- single point optimised output or range of power outputs
- continuous operation with extra power absorbed by the battery or stop-start to match demand
- Driving experience
- seamless power delivery
- consistent overrun braking
- quiet operation of the range extender
- Emissions
- fast warm-up and operation of exhaust treatment
- fuel quality, storage and evaporation over long term EV only use
References
- Could extended-range EVs nudge more car buyers toward full electric?, McKinsey and Company
- Understanding Scout’s New Range-Extender, Evan Coder, LinkedIn