Speed Limiters for Electric Vehicles: Do EVs Need Them?

Yes, electric vehicles need speed limiters in exactly the same circumstances as diesel or petrol equivalents. Any electric HGV over 3.5 tonnes or electric bus carrying more than eight passengers for hire and reward must have a speed limiter fitted by law. For electric vans and lighter commercial vehicles, speed limiters are not legally mandatory but offer the same fleet safety, fuel cost, and insurance benefits as on conventional vehicles. AutoKontrol’s System 80 speed limiter is fully compatible with electric drivetrains and integrates directly through the vehicle’s motor controller.

The Legal Position: EVs Are Not Exempt

The Road Vehicles (Construction and Use) Regulations 1986 require speed limiters on goods vehicles over 3.5 tonnes GVW and passenger vehicles with more than eight seats used for hire and reward. These regulations apply to the vehicle, not to the drivetrain type. An electric HGV has exactly the same legal obligation as a diesel one.

As the UK fleet market transitions to electric — driven by the zero-emission vehicle mandate and clean air zone requirements — the number of electric commercial vehicles requiring speed limiters is increasing rapidly. Electric vans from manufacturers like Mercedes-Benz (eSprinter), Ford (E-Transit), Renault (E-Tech Master), and Vauxhall (Movano Electric) are now common in delivery, service, and utility fleets.

Many of these electric vans have manufacturer-set top speeds, sometimes limited to around 75-80 mph. However, a manufacturer top-speed setting is not a calibrated, certified speed limiter. It does not come with tamper-evident seals, a calibration certificate, or the ability to set a fleet-specific speed. For operators who want to limit their electric vans to 60, 65, or 70 mph — or who need location-based speed control with GeoKontrol — an aftermarket speed limiter is still required.

How Speed Limiters Work on Electric Drivetrains

On a conventional diesel vehicle, a speed limiter restricts speed by modulating the electronic throttle signal — the signal between the accelerator pedal and the engine management system. This is known as drive-by-wire speed limiting.

On an electric vehicle, the principle is identical but the components are different. Instead of an engine management system controlling fuel injection, an electric vehicle has a motor controller (also called an inverter) that controls the power delivered to the electric motor. The accelerator pedal sends a signal to the motor controller, and the motor controller adjusts the torque output accordingly.

A speed limiter on an electric vehicle intercepts the signal between the accelerator pedal and the motor controller, limiting the maximum torque request when the vehicle reaches the set speed. The integration is cleaner than on many diesel vehicles because electric drivetrains are entirely electronic — there are no mechanical throttle cables, turbo actuators, or fuel pump governors to complicate the interface.

CAN Bus Integration

Most modern electric commercial vehicles use a CAN bus network for communication between vehicle systems. The speed limiter can read the vehicle speed directly from the CAN bus — a highly accurate and reliable speed source — and send its torque limitation commands through the same network.

This means the speed limiter is fully integrated into the vehicle’s electronic architecture rather than being an add-on that taps into individual wires. The result is smoother operation, faster response times, and better compatibility with the vehicle’s other electronic systems including regenerative braking, traction control, and stability management.

EV-Specific Considerations

While the basic principle of speed limiting is the same for electric and combustion vehicles, there are several EV-specific factors that affect how the limiter is configured and operates.

Regenerative Braking

Electric vehicles use regenerative braking — the electric motor acts as a generator when the driver lifts off the accelerator, converting kinetic energy back into battery charge. This creates a natural deceleration effect.

When a speed limiter reduces the torque request to maintain the set speed, it works in harmony with regenerative braking. The vehicle decelerates smoothly and recovers energy at the same time. This is actually a better experience than on diesel vehicles, where lifting off the throttle at the limiter speed relies on engine braking alone.

Instant Torque Delivery

Electric motors deliver maximum torque from zero rpm. This means an electric van can accelerate very rapidly from a standstill — faster than many drivers expect, and faster than the equivalent diesel model. In urban environments, depots, and car parks, this instant torque can be a safety concern.

Speed limiters, particularly when combined with GeoKontrol zone control, address this by limiting not just the top speed but effectively the rate at which the vehicle can accelerate in speed-restricted zones. A vehicle limited to 10 mph in a depot zone will have its torque request managed to prevent aggressive acceleration even if the driver stamps on the pedal.

High-Voltage Safety

Electric commercial vehicles operate at voltages between 400V and 800V. The speed limiter installation must respect the high-voltage safety boundaries of the vehicle. AutoKontrol engineers are trained in high-voltage vehicle systems and ensure that speed limiter installation does not interfere with, or compromise the isolation of, the high-voltage drivetrain.

The speed limiter itself operates on the vehicle’s standard 12V or 24V auxiliary system and communicates with the motor controller through the low-voltage CAN bus network. There is no direct connection to the high-voltage system.

Range Considerations

Fleet operators transitioning to electric vehicles are acutely aware of range. Every mile of range matters, and anything that reduces efficiency is a concern.

Speed limiters actually improve range on electric vehicles, for the same reason they reduce fuel consumption on diesel vehicles: aerodynamic drag increases with the square of speed. Reducing maximum speed from 70 mph to 62 mph can improve real-world range by 10-15%, depending on the journey profile. For fleet operators managing tight depot-to-depot range requirements, this is a meaningful benefit.

Compatibility with Current Electric Commercial Vehicles

AutoKontrol has developed speed limiter solutions for the current generation of electric commercial vehicles. For a comprehensive overview of compatibility across electric and hybrid platforms, see our detailed guide to speed limiters for electric and hybrid vehicles.

Our engineering team maintains an up-to-date compatibility database and develops new vehicle interfaces as new electric models enter the UK market. If your fleet is transitioning to electric — or running a mixed fleet of diesel and electric vehicles — we can provide a consistent speed limiter solution across all vehicle types.

The Fleet Electrification Opportunity

Fleet electrification and speed limiter installation can be coordinated to reduce cost and downtime. If vehicles are being prepared for entry into service — whether new purchases, lease returns being recommissioned, or conversions — speed limiter installation can be completed at the same time as other pre-delivery checks.

For fleets already running electric vehicles without speed limiters, AutoKontrol’s mobile fitting service can install and calibrate systems at your premises, typically completing each vehicle in two to three hours.

Get Started

Whether you are planning a fleet electrification programme or need speed limiters on existing electric vehicles, AutoKontrol can provide a solution tailored to your specific vehicle types and operational requirements. Request a free quote to discuss your EV speed limiter needs.