Evrest-project
Main results

E V R E S T Main Results

Electric Vehicle with Range Extender as a Sustainable Technology

Key Figures of the E V R E S T Concept

The main results summarise how an electric vehicle with a range extender combines battery-electric driving with an onboard generator to deliver a sustainable and practical transport solution.

2
Energy sources: battery and onboard generator
1
Electric traction system driving the wheels
3
Core operating modes assessed in the project
100%
Focus on electric propulsion at all times

Principal Findings

Two findings stand out from the analysis of the E V R E S T architecture in everyday use.

Electric vehicle with range extender on a city road
Energy use

Efficient daily driving on the battery

For most daily trips the vehicle runs on stored battery energy alone. The electric drive keeps energy losses low at urban speeds, where regenerative braking recovers a significant part of the kinetic energy that a conventional car would lose as heat.

Charging connector attached to an electric vehicle
Range

Range extension without grid dependence

When the battery reaches its lower charge threshold, the range extender generator supplies electricity to the traction motor. The driver keeps the same driving experience, and the vehicle can cover longer journeys where charging points are scarce.

Sustainability Benefits

The E V R E S T approach reduces the need for a very large battery. A smaller battery lowers the mass of raw materials, the embodied emissions of manufacturing and the pressure on charging infrastructure. The vehicle therefore addresses several sustainability goals at once.

  • Smaller battery pack with reduced material demand
  • Lower range anxiety and fewer dependencies on fast charging
  • Electric traction for quiet, zero-tailpipe urban driving
  • Flexible fuel use for longer journeys
Battery and drivetrain components of an electric vehicle

Operating Modes in Practice

The results confirm that the choice of operating mode strongly affects efficiency. Battery-led driving is most efficient at low and moderate speeds. Range-extender operation is best kept near the generator's optimal load, which avoids inefficient part-load running and keeps emissions low.

Battery modeRange-extender modeEnergy management
Dashboard showing energy flow in an electric vehicle

Frequently Asked Questions

A range extender is a small generator, usually driven by an internal combustion engine, that produces electricity to charge the battery or power the electric motor. The wheels are always driven electrically.

It allows a smaller battery, reduces dependence on public charging and lets the generator run in its most efficient load range, which lowers overall energy use compared with a conventional combustion vehicle.

The full analysis is presented in the project deliverables, and the wider context is described in the project overview.

Explore the Full E V R E S T Project

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