Why Electric Vehicles Have Lower Range and Top Speeds Compared to Petrol and Diesel Cars

Many electric vehicle (EV) enthusiasts often wonder:

“Why do EVs have electronically limited top speeds?” and

“Why is their driving range shorter than internal combustion engine (ICE) cars?”

The answers lie in understanding energy density differences between fuels and EV batteries, and how this affects performance, range, and refueling times.

Petrol vs Diesel vs Electric: Energy Content Comparison

Let’s break down the energy content of common fuels:

1 liter of petrol = 9 kWh

1 liter of diesel = 10 kWh

So, a 40-liter fuel tank holds:

360 kWh (petrol)

400 kWh (diesel)

In contrast, a typical EV battery in a compact car has a net usable capacity of only 50–80 kWh. This "net" value is crucial. Manufacturers reserve part of the total capacity as top and bottom buffers to preserve battery health, meaning drivers can’t use the full battery charge.

In fact, most manufacturers recommend keeping your EV battery between 20% and 80% charge during daily use to extend lifespan.

Comparing Real-World Efficiency and Range

Let’s look at the Peugeot 208, a model available in petrol, diesel, and electric versions:

Model Energy Content (kWh) Consumption (kWh/100 km) Range (km)

Peugeot 208 1.2 PureTech 396 47.7 830

Peugeot 208 1.5 BlueHDi 410 40.0 1025

Peugeot e-208 (Electric) 45 15.4 292

Key takeaway:

EVs are about 3x more efficient than ICE cars (thanks to up to 94% drivetrain efficiency vs 38–40% in ICEs), but the energy content of their “fuel” (battery) is far lower.

To match the range of:

The petrol version, an EV would need ~128 kWh usable battery

The diesel version, around 158 kWh

But such large batteries would increase weight, cost, and energy consumption, making them impractical with today’s lithium-ion tech.

Refueling vs Charging Speed

Refueling is another major gap area:

Fuel Type Charging/Refill Power (kW)

Petrol 13,500 kW

Diesel 15,000 kW

Electric 270 kW (best case)

EVs like the latest models from Tesla or Hyundai can charge at up to 270 kW, but it still takes 20–30 minutes to get a significant charge. Compare that to 2 minutes at the pump for petrol/diesel, which effectively delivers thousands of kilowatts of “charging power”.

That said, EVs can be charged overnight at home, something ICE vehicles can’t do. And solid-state battery tech on the horizon promises better range and faster charging—potentially narrowing the gap further.

Conclusion

EVs are more efficient, but still carry far less energy than fuel tanks.

Range and charging speed remain limited by today’s battery tech.

Solid-state batteries and ultra-fast charging could soon change the game.