Does E10 gasoline make cars consume more fuel?

Many believe that E10 bioethanol fuel may cause vehicles to consume more fuel or perform less efficiently compared to traditional RON95 gasoline. However, test results from a research team led by Associate Professor Dr. Dam Hoang Phuc ( Hanoi University of Science and Technology) show the opposite under certain real-world operating conditions.

The university's research team collaborated with PetroVietnam BSR and Toyota to conduct a direct comparative test between RON95, E5, and E10 gasoline on the Toyota Corolla Cross model, including both internal combustion engine (ICE) and hybrid (HEV) versions.

The tests were conducted in the laboratory as well as under real-world operating conditions in Hanoi, including the inner city area during peak and off-peak hours, and on Thang Long Boulevard.

The results show that urban traffic congestion is the best condition for E10 gasoline to perform well: Vehicles using internal combustion engines running on this fuel type have a fuel consumption reduction of about 2.3% compared to RON95. For hybrid versions, the reduction is up to 7.8%.

Even at high speeds of around 90-120 km/h, E10 showed lower fuel consumption than RON95 in testing.

Experimental results show that E10 gasoline helps reduce fuel consumption compared to RON 95 mineral gasoline. (Photo: FBNV)

Regarding performance, Associate Professor Dr. Dam Hoang Phuc stated that internal combustion engine vehicles may experience a power reduction of approximately 6% during maximum acceleration when using E10 fuel. However, under normal urban driving conditions, this difference is difficult to notice significantly.

Meanwhile, in hybrid vehicles, E10 helps increase power by about 2.15%. "The high octane of ethanol comes into play when the hybrid system controls combustion," Mr. Phuc explained.

Associate Professor Dam Hoang Phuc at the announcement of research results in 2023. (Photo: Manh Hung)

In addition to fuel consumption, the research team also noted a significant reduction in harmful emissions when using E10. Specifically, internal combustion engine vehicles reduced hydrocarbon (HC) emissions by approximately 10.87% and CO emissions by nearly 15% compared to when using RON95.

According to recommendations, modern vehicles can use E10 normally. The main group to note is older vehicles using carburetors, especially those manufactured before 2000 or vehicles that have been left unused for a long time. In these cases, users should fill the tank with a moderate amount of fuel and use the vehicle regularly to minimize the risk of moisture absorption and fuel phase separation.