Abstract: Air pollution is a major global problem as it harms the human respiratory system, plants and property. Among all the pollution sources in a city the road transport emissions are often the most important source. In nowadays there is a great increase in car ownership and use. Therefore, it remains to be seen what measures needs to be adopt, in order to reduce emissions from road traffic and consequently to prevent transport related air pollution problems. One solution of reducing emissions from road traffic is the use of alternative fuels. Alternative fuels are derived from resources other than petroleum. Some are produced domestically, reducing dependence on foreign oil and some are derived from renewable sources. Alternative fuels produce less pollution than gasoline or diesel. The transportation fuels that are made from biomass through biochemical or thermochemical processes are known as biofuels. Examples of well known alternative fuels and particularly biofuels include biodiesel, ethanol and methanol. This paper examines the behavior of a small four-stroke engine when mixtures of gasoline-ethanol and gasoline-methanol are used as fuel. This engine moves a small alternative generator. CO and HC emissions tests were conducted using different mixtures of gasoline-ethanol and gasoline-methanol as fuel, under different load conditions: under full electrical load and without load conditions. These tests showed that when the percentage of ethanol and methanol in the fuel increases the CO and HC emissions decrease. There was an exception with the mixtures: gasoline-90%ethanol, 100%ethanol, for which the engine malfunctioned and the HC emissions were increased. During the tests the regulation of the engine relatively to the air/fuel ratio, maintained the original adjustment that concerned gasoline. It is important to mention that the ethanol that was used was 95ï alcoholic degrees and not 100% pure ethanol. Furthermore, during the use of the mixtures of gasoline-ethanol and gasoline-methanol there was a small increase of fuel consumption when the percentage of the ethanol and methanol in the fuel was increased.

Brief Biography of the Speaker:
Dr. Charalampos Arapatsakos is a Greek citizen, who has been born in Athens. He has studied Mechanical of Engineering. He is a Ph.D. Assoc. Professor in the University of Thrace in Greece. At the present he is a member of Technical Chamber of Greece, member of Electrical and Mechanical Engineering Association and member of Combustion Institute of Greece too. Mr C. Arapatsakos has participated in many research programs about biofuels, gas emissions and antipollution technology. His research domains are mainly on biofuels and their use in internal combustion engines, the power variation from the use of biofuels, the gas emissions and mechanical damages.