Nowadays more and more emphasis is placed on the protection of the natural environment. Scientists notice that global warming is associated with an increase of carbon dioxide emissions, which results inter alia from the combustion of gasoline, oil, and coal. To reduce the problem of pollution from transport, the EU is introducing increasingly stringent emission standards which should correspond to sustainable conditions of the environment during the operation of motor vehicles. The emissivity value of substances, such as nitrogen oxides (NO_x), hydrocarbons (HC), carbon monoxide (CO), as well as solid particles, was determined. The aim of this paper was to examine, by means of simulation in the Scilab program, the exhaust emissions generated by the 1.3 MultiJet Fiat Panda diesel engine, and in particular, carbon monoxide and nitrogen oxides (verified on the basis of laboratory tests). The Fiat Panda passenger car was selected for the test. The fuels supplied to the tested engine were diesel and FAME (fatty acid methyl esters). The Scilab program, which simulated the diesel engine operation, was the tool for analyzing the exhaust toxicity test. The combustion of biodiesel does not necessarily mean a smaller amount of exhaust emissions, as could be concluded on the basis of information contained in the subject literature. The obtained results were compared with the currently valid EURO-6 standard, for which the limit value for CO is 0.5 g/km, and for NO_x − 0.08 g/km, and it can be seen that the emission of carbon monoxide did not exceed the standards in any case examined. Unfortunately, when analyzing the total emissions of nitrogen oxides, the situation was completely the opposite and the emissions were exceeded by 20–30%.

Economic progress, development of transport, production of new cars, production of more and more energy, and the combustion of fossil fuels are causing huge changes that are currently occurring in the environment. Ecological problems of the contemporary economy combined with perspectives of resources exhaustion, as well as the need to follow sustainable rules of living, require the search for new fuels. Fuels which can assure their availability and good environmental performance are needed for maintaining sustainable transportation. Knowledge about the behavior of various fuels is necessary for realistic methods of technology management in transportation means and the fuel industry. This paper describes biofuels that can be an addition to petrol or can exist as standalone fuels. A simulation was carried out on an urban vehicle and the tested fuels were petrol 95, ethanol, methanol, and dimethyl ether. For the selected engine a simulation corresponding to that of the New European Driving Cycle (NEDC) test was created using the Scilab package. Based on this simulation, values of carbon dioxide and water vapor emission were determined. The fuel demand for each fuel mixture and the amount of air for the fuels used were also calculated (and verified on the basis of laboratory tests). It was demonstrated that addition of biofuel decreases emission of carbon dioxide, simultaneously increasing emission of water vapor. Biofuel additive also caused an increase in fuel consumption. Unfortunately, in the New European Driving Cycle test being investigated, carbon dioxide emissions in all cases exceeded the permissible level of 130 g CO₂/km, which is bad news in the context of the further tightening of norms and standards. The simulation tests confirmed that when using the start/stop system and applying specific additives, the carbon dioxide emission decreases and the consumption of mixtures with the activated start/stop system is smaller. The analyzed problems and results of this analysis become more important in light of the Worldwide Harmonized Light Duty Vehicles Test Procedure (WLTP) standard, which became binding from September 2018 and applies to the sale of cars that had been approved prior (in accordance with the New European Driving Cycle standard). Although the NEDC standard appears obsolete the computer model simulating this type of test will be necessary in many cases. It is, however, needed and possible to develop a similar simulation procedure for WLTP tests.

Managing of wastes rich in lignocellulose creates the opportunity to produce biofuels that are in full compliance with the principles of sustainable development. Biomass, as a suitable base for the production of biofuels, does not have to be standardized, and its only important feature is the appropriate content of lignocellulose, which assures great freedom in the selection of input. Biobutanol, obtained from this type of biomass, can be used as fuel for internal combustion engines, including diesel engines. In the era of strict environmental protection regulations, especially concerning atmospheric air, any new fuel, apart from good energetic properties, should also show beneficial ecological effects. This study investigates the carbon dioxide emissions from biobutanol powered diesel engine by means of use of the simulation model. The parameters of a real passenger car powered by a diesel engine were used for simulation carried out accordingly to the WLTP (Worldwide Harmonized Light Vehicle Test Procedure) approval procedure as the current test for newly manufactured cars. The results obtained for biobutanol were compared with simulated exhaust emissions obtained for conventional diesel and with FAME (fatty acid methyl esters)—the most popular biofuel. Biobutanol, in spite of its higher consumption, showed lower direct carbon dioxide emissions than both: the conventional diesel and FAME. In addition, a LCA (life cycle assessment) was carried out for the fuels and vehicles in question using the SimaPro package. Therefore, the implementation of butyl alcohol as a fuel provides favorable environmental effects. This result gives arguments towards biofuel production management indicating that implementation of biobutanol production technology mitigates carbon dioxide emission, as well as promotes lignocellulosic resources rather than edible parts of the plants.

The depletion of conventional energy sources, including crude oil, is one of the cause of the search for alternative carriers and fuels in order to prevent an energy crisis. Due to the progressing climate change, each new solution must comply with the principles of sustainable development. Dynamic development in the transport sector and, as a consequence, the increase in the number of vehicles on the roads negatively affect the atmosphere and the environment, which is why the share of biofuels, which are used to minimize this negative impact, is steadily increasing. This paper analyzes the emissivity (emission capability) of biofuels such as fatty acid methyl esters (FAME), ethanol, dimethyl ether and butanol and compares them with conventional fuels. A computer simulation was used, based on the real parameters of vehicles and fuels. The test procedure was carried out in accordance with the appropriate New European Driving Cycle (NEDC) approval test for such cars. In addition, a life cycle assessment (LCA) for the fuels and vehicles in question was carried out using the SimaPro package. Based on the results obtained from the z computer simulation, it was found that diesel fuel showed lower emissivity than petrol and its alternatives. However, FAME fuel provided more carbon dioxide than conventional diesel. As far as petrol is concerned, it was less emissive than dimethyl ether. Ethanol and butanol reduced emissions by 7% and 15%, respectively. After taking into account CO₂ emissions generated in the production process, both FAME and butanol were not very favorable in the context of other fuels. The results might be used for appropriate fuel use management.