Renault-backed combustion engine firm Horse has revealed a range-extender powertrain that has been designed to allow easy conversions of battery-electric vehicles.

The new set-up, which will be shown by the Renault, Geely and Aramco joint-venture at the Munich motor show, comprises a naturally-aspirated 1.5-litre four-cylinder engine with an integrated generator and inverter. It produces up to 94bhp and is claimed to be no larger than a briefcase. As such, the unit – named C15 – can be installed in the ‘frunk’ of an EV or at its rear end; either horizontally or vertically.

There will also be a turbocharged version designed for D-segment models and commercial vehicles, capable of putting out 161bhp.

The engines have been designed to run on petrol, synthetic fuels and ethanol or methanol flex-fuel; and are said to be compliant with the upcoming Euro 7 emissions regulations.

Neither has been designed to drive a car’s wheels. Instead, they will run in their most efficient rev range for generating electricity for an EV’s drive battery, balanced against noise, vibration and harshness requirements.

Horse CEO Matias Giannini said: “Range extended EVs [REEVs] are the fastest-growing powertrain category in many global markets. The Horse C15 range extender solution offers [car companies] a straightforward and cost-effective way to tap into this opportunity, and adapt their native BEV platforms into REEVs. We believe demand for REEVs will continue to grow.”