Effects of Ethanol Blend Fuels E10 and E85 on the Non-Legislated Emissions of a Flex Fuel Passenger Car

A well-balanced use of alternative fuels worldwide is an important objective for a sustainable development of individual transportation.

Several countries have objectives to substitute a part of the energy of traffic by ethanol as the renewable energy source.

The global share of Bioethanol used for transportation is continuously increasing.

Investigations of limited and unregulated emissions of a flex fuel vehicle with gasoline-ethanol blend fuel have been performed in the present work on the chassis dynamometer according to the measuring procedures, which were established in the previous research in the Swiss Network to adequately consider the transient (WLTC) and the stationary operation (SSC).

The investigated fuel contained ethanol (E), in the portions of 10% & 85% by volume.

The investigated vehicle represented a newer state of technology and an emission level of Euro 5. The engine works with homogenous GDI concept and with 3-W-catalyst (3WC).

Since there is a special concern about the particle emissions of gasoline cars with direct injection, the nanoparticle counts measurements were systematically performed with SMPS at stationary and with CPC at dynamic operation.

The non-legislated gaseous emissions were tested at the tailpipe with FTIR, this with special focus on NH₃, N₂O and HCHO (Formaldehyde).

The main results obtained from the investigated test vehicle are:

• the particle counts emissions are generally significantly reduced with Ethanol blend fuels at all operating conditions,
• in WLTC there is a clear increase of NH₃ with E85 and an insignificant tendency of increasing NH₃ with E10,
• with all fuels (E0, E10 & E85) there are no emissions of N₂O and no increase of HCHO (below 1 ppm), in WLTC warm,
• at cold start (22-25°C) there are emission peaks with all investigated fuels, with Ethanol blends there are emission peaks of Formaldehyde HCHO, which do not exist with gasoline and which are higher with higher Ethanol content.

The present research did not address the durability aspects and the cold startability in extreme conditions.