In article the market for electric buses in the world and in Poland have been discussed. The test methods for energy consumption of citi buses in Poland and the appropriate measuring devices have been presented. The article presents the results of the energy consumption of the citi bus in the test SORT 2. The results obtained were referred to results in the case other electric and conventional buses.

Currently produced diesel engines of different manufacturers, used for the same applications, have comparable specific fuel consumption. Therefore, the laboratories measuring fuel consumption, especially in comparative tests, require the use of more accurate methods of measurement. The Environmental Protection Centre of Motor Transport Institute has recently implemented the fuel consumption measurement method using KMA Mobile flow meter produced by AVL company. This device allows to carry out measurements by both volumetric and mass method, thanks to builtin device for measuring the fuel density. Due to some customers requirements the laboratory began with preparations for obtaining accreditation of the Polish Centre of Accreditation for the procedure of measuring fuel consumption by volumetric and mass method. One of the requirements of the Polish Centre for Accreditation is carrying out the validation of the new method. It can be done by comparing the results obtained with new method with the results of the method already validated. The validated method is described in the regulation. This is the carbon balance method described in UN-ECE Regulations No. 101. The calculation of fuel consumption according to this method is based on a measurement of pollutants emissions of carbon dioxide (CO2), carbon monoxide (CO) and hydrocarbons (THC). This paper describes the fuel consumptions measuring procedure using two methods: mass method using a AVL KMA Mobile flow meter and carbon balance method using the AVL AMA i60 analyzers. To verify measurement results additionally there was fuel consumption measured with using a scale, as a difference of the external fuel tank mass change, from which the vehicle was fuelled during the tests

The reduction of emissions of harmful exhaust gases is one of the main aspects in broadly understood automotive sector. Representatives of the European Union are encouraging vehicle manufacturers to comply with increasingly stringent standards related to the emission of harmful substances in passenger cars. From 2020, the new standard for CO, HC and NOX road emissions from these vehicles will come into force. It also assumes average CO2 emissions from fleets producer car at the level of 95 g/km. It is a big challenge. The emission of harmful emissions is also a problem during the operation of vehicles. In real traffic conditions, a big challenge is the need to reduce average driving speeds due to emissions of harmful exhaust substances. With increasing driving speed, it increases. Therefore, the authors of the article decided to investigate the problem on the initial road and highway. In our research, mobile PEMS type testing equipment was used for tests of vehicles with emission standards: EURO 5 and EURO 6. The tests were carried out in real traffic conditions on a fast-moving and motorway road with speeds up to 110, 120, 140 and 160 km/h. The research was aimed at showing differences in the level of exhaust emissions of emitted vehicles resulting from the speed of travel. In the article, on the basis of the tests carried out, speed was determined and recommended, which from the point of view of emission will be optimal for efficient and ecological movement on this discussed type of roads.

The paper presents results of the pollutants emission measurements from the exhaust system of the forklift truck as a representative of the off-road mobile machinery operating in real conditions. Directive 96/68/EC does not include spark ignition engines with maximum power output greater than 19 kW. In order to check the emission characteristics of the off-road mobile machinery equipped with such engine, the tests have been carried out of the H16T type forklift truck, manufactured by Linde company, fuelled with LPG. The portable analyzer (PEMS) Semtech-DS by Sensors was used for the measurements. It allowed making the necessary calculations to determine the road-test pollutants emission as a function of time. The tests included emission testing in stationary conditions and roadside emission testing of the forklift truck. The paper contains illustrations with many figures and tables showing CO, CO 2 , THC and NO x emissions versus speed, time and fork load of the tested machine. It contains discussion on the possibility of road emission measurements expressed in g/km for off-road machineries as well as usefulness of these measurements using portable emission measurement systems for the off-road machinery.

Due to finishing of conventional fossil energy resources, energy security, the desire of independence from imported fuels and reduction of emission of harmful compounds and greenhouse gases in the atmosphere, there is need to explore new technologies using alternative energy sources. One of alternative energy sources, which can be used in transportation, is natural gas. Natural gas can be use in two forms: as a gas (CNG-Compressed Natural Gas), and as a liquid (LNG-Liquefied Natural Gas). Currently the most often used is CNG fuel. The vehicles, which can be supplied by CNG or LNG fuels are called Natural Gas Vehicles (NGV). The article presents the basic properties of liquefied natural gas (LNG) used as a fuel for internal combustion engines. There were made the comparison of the characteristics of CNG, LNG and diesel oil as an engine fuels in different aspects. There was presented the measurement method and measurement equipment applied in the Motor Transport Institute, used to measure the fuel consumption of LNG bus in real traffic conditions in comparison to bus, supplied by diesel oil. The results of measurements in SORT tests were presented and compared with fuel consumption of similar buses fuelled with diesel fuel.