At the international workshop “Developing Biofuels in the New Era - Key Tasks for Building a Sustainable Fuel Future in Vietnam,” Pham Huu Tuyen, Director of the Center for Research on Power Sources and Autonomous Vehicles (Hanoi University of Science and Technology), presented findings from over a decade of research on the effectiveness of E5 and E10 biofuels on car and motorbike engines in Vietnam.

Tuyen said the center began research and testing biofuels in 2010-2011, supported by the Ministry of Industry and Trade and in collaboration with fuel producers and car and motorbike manufacturers.

The goal was to comprehensively assess the feasibility of biofuels for common vehicles, providing a scientific basis for Vietnam’s implementation roadmap.

Studies used a comparative method: using the same engine model, the same car or motorcycle, operated under identical conditions, and the only variable was the fuel type (mineral gasoline, E5, and E10).

Notably, since testing started early, the fuel types included a variety of blends such as RON92, E5RON92, E10RON92, later expanding to RON95, E5RON95, and E10RON95.

Key evaluation criteria included engine power (kW)/torque (N·m), fuel consumption (g/kWh, liters/100 km), and emissions components.

Specifically, in tests on a 2003 electronically fuel-injected car, performance and fuel consumption were similar between RON92, E5RON92, and E10RON92 fuels.

Evaluated metrics included power (kW)/torque (N/m), fuel consumption (g/kWh, liters/100km), and emission components.

In tests on 2003 electronically fuel-injected cars, performance and fuel consumption were similar for RON92, E5RON92, and E10RON92 fuels.

Cars using E10 had a 33 percent reduction in CO emissions and 18 percent in HC compared to RON92 mineral gasoline.

Acceleration improved significantly. For the same test car, E10 gained 0-100 km/h in 15.7 seconds, compared to 19 seconds for mineral gasoline, proving that E10 is not only eco-friendly but also enhances performance.

In tests on a 2015 model with electronic fuel injection, cars using RON95 and E10RON95 started easily, with no differences for different fuels. However, cars using E10 had CO emissions reduced by 19.3 percent, HC by 30.3 percent, and fuel consumption decreased by 2.42 percent compared to RON95.

Idle-mode emission tests on 12 car models with different production years showed reductions in CO, HC, and NO when using E10RON95.

A similar method was applied to 2020-model motorcycles with electronic fuel injection. When using E10, acceleration from 20-80 km/h took only 15.9 seconds, while it was 15.95 seconds for RON95.

Under full-load operation, motorcycles using E10 had CO emissions reduced by 10.9 percent and HC by 11.7 percent compared to RON95. In standard cycle tests, CO emissions were down by 24.9 percent and HC by 12.6 percent with E10.

Idle-mode emission tests on nine motorcycle models with various years of manufacturing also showed reductions in CO, HC, and NO when using E10RON95.

Tuyen said durability tests were also conducted on older vehicles: 1999 carburetor motorbike, 20,000 km; two 1995 carburetor engines, 300 hours; six 2003 cars with carburetors or electronic fuel injection, 20,000 km) using RON92 and E10RON92.

Durability indicators included wear on key components like pistons and cylinders, changes in technical performance (e.g. power, fuel consumption), exhaust gas quality, and lubricant condition.

Results showed that the degradation levels between RON92 and E10RON92 were similar and within acceptable limits.

For newer vehicles, manufacturers have confirmed that they are compatible with E10, Tuyen emphasized.

Compatibility tests on older fuel system components (carburetor motorbikes, carburetor cars, pre-2010 electronic fuel pumps) via fuel immersion showed similar changes for RON92 and E10RON92, with E10RON92 having a more pronounced effect on rubber and copper parts in carburetors.

Tuyen concluded that E10 generally has positive effects on vehicles, improving power and reducing fuel consumption.

Additionally, E10 reduces harmful CO and HC emissions, as ethanol (used in E10 blending) is bio-based, renewable, and lowers CO2 emissions.

“Our research and global studies all show E10 is suitable for most vehicles in use, though it may affect older carburetor-based vehicles,” he said.

Thus, Tuyen recommended that car and motorbike manufacturers and importers in Vietnam publish lists of E10-compatible models and provide warnings if needed.

They could also support owners of older vehicles by specifying which incompatible parts or materials need replacement, reassuring the public in transitioning from mineral gasoline to E10, Tuyen suggested.

It is expected that from January 1, 2026, all gasoline produced, blended, and distributed nationwide for gasoline-powered motor vehicles must be E10.

From January 1, 2031, all gasoline sold for motor vehicles must be E15 or other biofuel blends as prescribed by the Minister of Industry and Trade.

Tam An