A new era for extreme off-road vehicles
Fording deep water and tackling extreme off-road routes is entering a new technical dimension. The Horse Powertrain division — the entity created to develop internal combustion and hybrid engines within the Renault Group and its partners — has unveiled an innovation unprecedented in the production automotive industry: the Horse B20 powertrain.
Designed specifically for the harshest environmental conditions, this internal combustion engine is the first in the world capable of operating completely submerged in water, redefining endurance standards for the next generation of off-road vehicles.
Technical architecture and record efficiency
At the heart of the new Horse B20 is a 2.0-liter 4-cylinder petrol unit, designed with a low weight of just 130 kilograms. Despite its compact dimensions, the engine offers a flexible power range and high performance:
- Maximum power: between 190 and 252 hp;
- Engine torque: between 300 and 380 Nm;
- Operating cycle: Miller, optimized for low consumption and low emissions;
- Thermal efficiency: 48.4%, a top value for series internal combustion engines.
The versatility of the new powertrain is designed directly for electrification. The Horse B20 can operate in simple hybrid (HEV), plug-in hybrid (PHEV) or extended-range electric vehicle (EREV) systems, in which the combustion engine functions exclusively as a generator to charge the batteries.
Underwater engineering and IPX8 certification
What radically differentiates the Horse B20 from any other propeller on the market is its resistance to the aquatic environment. The motor can operate without problems underwater up to a depth of 1.1 meters, being created according to the IPX8 insulation standard.
To achieve this extreme off-road performance, engineers have integrated a series of dedicated technical solutions:
- Advanced sealing: A special sealing structure for the joint between the engine and transmission, complemented by torsional vibration dampers.
- Dual active cooling system: Maintains the optimal engine block temperature both on dry land and during total immersion.
- Adaptive Electronic Management: At the moment of dive, dedicated sensors send real-time data to the electronic control unit (ECU), which automatically adjusts throttle response and delivers optimal power.
- 100% gradeability: The lubrication and fuel system is designed to function flawlessly even when tackling extremely steep slopes, with a grade of up to 100% (45 degrees).
Official debut and series applications
The first public appearance of the new Horse B20 engine took place at the Beijing Auto Show. The working prototype was mounted under the hood of the Geely Galaxy Cruiser 700, a large off-road vehicle intended for the Chinese market.
The development of the B20 unit paves the way for a new series of 4x4 vehicles ready for heavy expeditions. The new engine will be integrated into future Renault Group off-road models, but will also be supplied to other global automakers looking for a hybrid solution capable of withstanding the toughest demands of the outdoor environment.