Re-born Engine Innovations--Three Businesses Engineer Internal Combustion Engines for Decarbonization
Subaru Unveils Next-Generation e-BOXER Engine
Subaru has announced its next-generation e-BOXER engine, a significant advancement in hybrid technology. This innovative system combines a 2.5-litre naturally aspirated boxer 4-cylinder petrol engine with a powerful 90kW electric motor and a 1.1kWh lithium-ion battery pack, delivering a combined system output of 145kW [2][4].
Key Features and Technical Details
The e-BOXER engine is a horizontally opposed (boxer) 4-cylinder petrol engine, with an integrated 90kW electric motor and a 1.1kWh lithium-ion battery. The petrol variant uses a Lineartronic CVT with an 8-speed manual mode, optimized for stronger take-off acceleration and downhill performance. The hybrid variant manages electric and engine power seamlessly [1][4]. Both variants maintain Subaru's hallmark all-wheel-drive capability.
Fuel Efficiency and Emissions
The hybrid system drastically improves fuel economy compared to the petrol-only version. The new Forester Hybrid achieves a claimed fuel consumption of 6.2L/100km, significantly better than the petrol-only model’s 7.9L/100km. CO2 emissions drop from 180g/km to 140g/km, indicating a substantial environmental benefit due to the hybrid powertrain [1][4].
Strategic Move for Subaru
The implementation of this hybrid system marks a strategic move by Subaru to sharpen the fuel economy and emissions profile of its popular SUV lineup without sacrificing power or Subaru’s distinct boxer engine character [2][4]. The electric motor output (90kW) is a large step up from Subaru’s previous mild hybrids, enabling stronger electric assistance and better overall system output [1].
Collaboration with Mazda and Toyota
Subaru's collaboration with Mazda and Toyota in developing carbon-neutral fuels is a testament to the competitive spirits of all three companies, constantly honing their technologies by facing off on the racetrack [5]. On May 28, Subaru, Mazda, and Toyota participated in the Multipathway Workshop, demonstrating their commitment to new engine development in the electrification era [6].
The Age of Decarbonization
The e-BOXER engine is not intended to extend the life of Internal Combustion Engines but rather to create a new engine for the age of decarbonization. Subaru's Chief Technology Officer, Fujinuki, aims to resonate strongly with Subaru's supporters and address the company's current weakness in fuel efficiency [6].
Basic Explanation of Engine Types
For a basic explanation of in-line, horizontally-opposed, and rotary engines, refer to the end of this article.
Conclusion
Subaru's next-generation e-BOXER engine innovatively merges a sizeable electric motor and battery with a 2.5L boxer petrol engine, significantly boosting combined power while improving fuel efficiency and reducing emissions, thus advancing Subaru's hybrid technology and environmental goals for the Forester [1][2][4].
Engine Types Explained
- In-line Engines: Engines where the cylinders are arranged in a straight line, usually found in most cars.
- Horizontally-Opposed (Boxer) Engines: Engines where the cylinders are arranged in pairs, one above the other, and opposite each other, so that the pistons move in and out in opposite directions, reducing vibration and improving balance.
- Rotary Engines: Engines where the rotor rotates around a central axis to create power, known for their compact size but high fuel consumption and durability issues. Subaru is the only mass-market brand currently producing horizontally-opposed engines.
The strategic move by Subaru to integrate a large electric motor and battery with a 2.5L boxer petrol engine in the next-generation e-BOXER engine signifies their focus on improving the fuel economy and emissions profile of their popular SUV lineup, while maintaining the distinct boxer engine character. This new approach is a significant advancement in Subaru's hybrid technology, aligning with the global shift towards decarbonization and electrification in the automotive industry, as well as the collaborative efforts between Subaru, Mazda, and Toyota in developing carbon-neutral fuels.
