Wheelie good idea! E-car engineers develop engine that sits inside WHEEL hub

KOMEL’s engineers have designed a 'direct drive' that’s placed in a car’s wheels. KOMEL/Facebook

How can the move to electric cars be eased, reducing C02 emissions? Polish engineers at the Institute of Drives and Electrical Machines (KOMEL) in Katowice have an answer: an engine placed directly inside a car wheel.

As electric cars gain popularity worldwide, the Polish government wants to have one million of them on its roads by 2025. An Electromobility Development Plan adopted by the government last year provides a roadmap for reaching this target.  

The move to e-cars would not only reduce air pollution caused by car emissions, but also create new opportunities for Polish businesses, spurring on innovation.

For now, though, e-cars remain relatively expensive, which is where KOMEL’s idea can help.

KOMEL’s engineers have designed a “direct drive” that’s placed in a car’s wheels.

While the current prototype weighs around 30kg, KOMEL’s engineers plan to develop on a lighter one.KOMEL/Facebook

Rather than sit in the car’s engine compartment, as is usually the car, the engine is built directly into the wheel hub.

Striking in its simplicity, this solution’s advantages include eliminating mechanical transmissions, which reduce efficiency and require maintenance, more space inside the car itself, relatively simple instalment and easier disassembly of the engine.

Drivers also have more control over the vehicle, because the rotational force on each wheel can be set separately.

Challenges include relatively little space for the engine and difficulty cooling it, KOMEL notes.

While the current prototype weighs around 30kg, KOMEL’s engineers plan to develop on a lighter one.

The solution could be used in a wide range of vehicles, from small city cars to delivery vans and buses.KOMEL/Facebook

For a small passenger car, two wheels with engines are plenty. Larger cars will require four, and buses even more.

The solution could be used in a wide range of vehicles, from small city cars to delivery vans and buses, the Institute suggests. An electric engine of this kind could also be used to supplement traditional combustion engines, turning the car into a hybrid.

The engine-in-wheel idea was developed as part of the "Innovative direct drive solutions for electric vehicles” project”, part of a broader project funded by Poland’s National Centre for Research and Development.

Based in the city of Katowice, in south-western Poland, KOMEL has been producing engines and electric drives for seven decades. With its own laboratories, it can test prototypes for new products, before manufacturing them at its own production plant.