The University of Nebraska’s Department of Chemical and Biomolecular Engineering recently released results of a study of 50 non-flex fuel vehicles from the State of Nebraska to determine the adaptability, economic feasibility, and environmental impact of using E30 (30% ethanol blend). Twenty-six vehicles were fueled by E15, and 24 vehicles were fueled by E30.
Each vehicle was equipped with a monitoring device to track different driving parameters in real time throughout the duration of the demonstration. Furthermore, the drivers were provided with driver logs to track fuel consumption. This data was analyzed to determine the long-term adaptability of non-FFVs to E30 and to demonstrate the economic feasibility and environmental impact of using higher ethanol blends.
Long-term fuel trim (LTFT) and O2 sensor readings were monitored to investigate whether the vehicle’s engine control module (ECM) can adapt to the increased oxygen concentration resulting from the added ethanol. The ECM controls the air/fuel ratio (AFR) by measuring the voltage generated through the oxygen sensor which indicates the proportion of oxygen in the exhaust.
The distribution of these two parameters was compared between vehicles operating on E30 and those operating on E15.
The study found an expected average increase in the LTFT of vehicles operating on E30; however, the distribution of O2 sensor readings for the two conditions were similar. This indicates that the ECM of the tested vehicles was able to account for the increased oxygen content in the fuel.
Furthermore, a similar comparison was implemented on coolant temperatures from vehicles running on each fuel type. The researches found that the increase in ethanol concentration does not cause engine coolant temperature to change significantly.
Finally, a number of more complex statistical data analyses were conducted to determine the effect of E30 on overall vehicle performance. Results from that analysis indicates no significant change in performance between the two fuel types.
The study also found no compromise in fuel efficiency due to the increase ethanol content of E30. Mileage obtained per gallon was comparable throughout the year.
The study went on to project that if only 10% of the 1.7 million registered non-FFVs in Nebraska converted from E10 to E30, ethanol consumption would increase by 18.5 million gallons per year and CO2 emissions would decrease by 64,000 tons per year.