Convert EV to a hybrid: Horse Powertrain retrofit kit

Stagnating growth in demand for battery electric vehicles in some markets has prompted UK-based Horse Powertrain to develop a modular hybrid system that retrofit an internal combustion engine to existing BEV platforms with minimal modifications.

The company, a joint venture between Renault Group and Geely with backing from Saudi oil giant Aramco, revealed its Future Hybrid Concept (FHC) at the 2025 Shanghai Auto Show as a plug-and-play solution for car-makers seeking powertrain flexibility.

The innovative unit combines an internal combustion engine, electric motor, transmission and power electronics, allowing manufacturers to convert existing BEVs into hybrids without major redevelopment or new production lines.

“For over a decade it looked like battery electric vehicles were the only path to net zero, and OEMs planned accordingly,” said Horse Powertrain chief executive Matias Giannini.

“However, we’re now shifting towards a technology-neutral world, with different markets and applications each pursuing their own sustainable mobility journey.”

The FHC bolts directly onto an EV’s existing subframe and replaces the front electric drive unit. Its compact, longitudinal layout fits into current BEV platforms without complete redesign, requiring only minor adjustments such as space for an exhaust system and fuel tank.

The powertrain supports petrol, E85 ethanol blends, methanol (M100), synthetic fuels and biofuels. The combustion engine works primarily as a range extender by recharging the vehicle’s high-voltage battery rather than powering the wheels directly, gaining all-wheel drive when paired with a rear electric axle.

Explaining the concept’s benefits, Mr Giannini said Horse Powertrain was focused on solving the biggest problems facing automotive manufacturers.

“Through our innovation, we can deliver a full hybrid powertrain system that seamlessly integrates onto a battery electric vehicle platform,” he continued.

“This compact, integrated powertrain concept allows OEMs to offer powertrain diversity with minimal disruption to the production process and resource expenditure.”

The FHC includes an integrated inverter, controller, DC-DC converter, onboard charger and an 800V fast-charging booster, making it compatible with high-speed charging networks.

At the Shanghai debut, Horse Powertrain showcased a range of new internal combustion engine and hybrid technologies, including compact range extenders.

Among them was the Gemini, a 1.0-litre, two-cylinder engine weighing just 91kg, designed as a generator for BEVs, producing 31kW and running on both petrol and methanol blends.

The company also unveiled a 1.0-litre turbocharged three-cylinder engine producing 89kW for flex fuels and a 1.5-litre engine with 115kW for plug-in hybrids.

Additionally, two 2.0-litre four-cylinder engines designed with a focus on thermal efficiency were introduced; one for methanol producing up to 151kW/375Nm and another for hydrogen producing 106kW/230Nm.

However, the Renault-Geely alliance is expected to be among the first to adopt the technology in its shared vehicle platforms.

A smaller-scale deployment is already underway, with Horse signing a contract to supply its 1.0-litre, three-cylinder extended-range BEV engine for a minibus in the South American market.

Horse Powertrain currently employs about 19,000 people across 17 factories and aims to produce approximately five million engines per year.

Horse says the first production vehicle equipped with the Future Hybrid Concept could arrive as early as 2028, although the company has not yet confirmed any commercial customers.

Renault and Geely each hold a 45 per cent stake in the joint venture, while Aramco holds the remaining 10 per cent, contributing its expertise in alternative fuels.