A revolution under the hood: what lies behind Horse Powertrain’s new engine?
Horse Powertrain has unveiled the HR12 LPG MHEV — the world’s first mass-produced engine to combine direct fuel injection with operation on liquefied petroleum gas (LPG). Production has begun in Romania, and the unit is already compliant with European standards.
The automotive world continues to debate the future of internal combustion engines. While some bet entirely on electric vehicles, others keep refining traditional powertrains. And now, in 2025, a true technological breakthrough has arrived: the first production engine that marries direct injection with LPG. The developer is Horse Powertrain, a joint venture between Renault and Geely.
At the core of the innovation is the HR12 LPG MHEV powertrain. It is based on a 1.2-liter three-cylinder engine paired with a 48-volt mild-hybrid system. The setup includes a belt-integrated starter-generator and a DC converter. This design not only saves fuel but also provides extra torque during acceleration and enables start-stop functionality.
In its current configuration, the engine delivers 138 hp at 5,500 rpm and 230 Nm of torque available from just 2,100 rpm. It can run on both gasoline and LPG. When switched to LPG, CO₂ emissions are reduced by 9% — a crucial advantage in Europe’s tightly regulated markets.
A key focus for engineers was the direct-injection system, specially adapted for LPG. The unit features an electronic vaporizer that ensures precise control of compression and fuel delivery. For added durability, the valvetrain has been reinforced. LPG is stored in a dedicated tank under the trunk floor, in the space usually reserved for a spare wheel.
Development and fine-tuning of the engine were carried out entirely in Romania, where Renault not only operates its Dacia brand but also maintains research centers. Series production began last week at the Mioveni plant. It remains undisclosed which models will receive the new engine, but it already meets Euro 6e and Euro 7 standards and is intended for both European and global markets.
Horse Powertrain’s ambitions go far beyond this project. Earlier this year at Auto Shanghai, the company showcased a full lineup of new engines, hybrid systems, and transmissions. Among them was the Future Hybrid concept, designed to turn EVs into hybrids with minimal platform modifications. This solution integrates an internal combustion engine, electric motor, transmission, and power electronics into a single module that can replace a standard EV drive unit. The hybrid setup can run on gasoline, ethanol, methanol, biofuels, and synthetic fuels — and also serve as a range extender for electric vehicles.
Other innovations include compact, fuel-efficient generator engines for EVs capable of running on multiple fuels, as well as new transmissions that improve the efficiency of hybrid and plug-in hybrid vehicles. For instance, a 1.5-liter engine producing 154 hp and 225 Nm is designed as a main power source for hybrids, with its automatic transmission pairing delivering up to 20% better efficiency than comparable systems.
Horse Powertrain is also working on 2.0-liter engines for mid-size and large vehicles, including a hydrogen-capable version. These units produce up to 201 hp and 375 Nm of torque, opening new opportunities for alternative fuels and expanding automakers’ options.
For now, it remains a mystery which models will debut with the innovative HR12 LPG MHEV. But one thing is clear: the company is betting on eco-friendliness, versatility, and efficiency. We’ll be following developments closely as the first cars with this unique engine arrive on the road.