To promote utilization of renewable fuels in transportation
sector, the Thai government has actively sought to obtain
higher-ratio ethanol blends in gasoline as early as 2007, at which
time E85 was introduced and fuel specifications were determined.
The purpose of this study is to evaluate E85 fuel performance in
flexible-fuel vehicles (FFVs) with considerations for tailpipe
emissions, formaldehyde, acetaldehyde emissions, evaporative
emission and vehicle performance. These findings will aid future
research in ethanol blends.
All tests were conducted utilizing three Volvo S40 FFVs and four
specific ethanol blend fuels: E10, E20, E50 and E85 (E-Fuels,
collectively). Tailpipe emission tests were conducted in full
compliance with Thailand Industrial Standard Institute; TIS 2160 -
2546 (Euro 3 legislation).
The three FFVs employed in this study demonstrated a comparable
tendency toward reduction of hydrocarbon (HC) and carbon monoxide
(CO) as ethanol content increased; however, acetaldehyde
concentration increased slightly in all cases, E85 exhibiting the
highest acetaldehyde yield. Fuel consumption of E85 increased
between 35 and 38% over that of E10. Evaporative emission test
results were in full compliance with Euro 3 limit values (≺2
g/test) for all E-Fuels, E85 the lowest of these due to reduced
raid vapor pressure (RVP). There was not a significant difference
in full-load power among E-Fuels.