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The nature and conditions of the execution of tests (open or duct flow) in terms of evaluating the flow rate generated by positive pressure ventilators (PPV) may affect the parameters of the drive unit recorded during testing. In this article, popular PPVs (conventional type—W1 and turbo type—W2) of about 4.2 kW were tested under open flow (Method A) and duct flow (Method B) conditions. During the tests, engine load values were recorded: torque, speed, horsepower and, using portable emissions measurement systems (PEMS), exhaust gas emissions: carbon monoxide (CO), carbon dioxide (CO2), hydrocarbons (HC), nitrogen oxides (NOx) and fuel consumption. Depending on the method used to measure ventilator flow rates, drive units can have different drive power requirements (from 3.2% to 4.5%). Changes in drive unit operating conditions induced by the flow measurement method are observed in the results of fuel consumption (from 0.65% to 9.8%) and emissions of harmful exhaust compounds: CO2 up to 2.4%, CO up to 67%, HC up to 93.2% and NOx up to 37%. The drive units of turbo type fans (W2) are more susceptible to the influence of the test methods in terms of flow assessment, where they have higher emissions of harmful exhaust gases when tested by Method A. Flow measurement methods affect the oscillation of propulsion power, which contributes to disturbances in the control of the fuel–air mixture composition. The purpose of this article is to analyse the impact of testing methods for measuring the flow rate of positive pressure ventilators on the performance of the drive unit.

Operating conditions often fluctuate during processing of branches and sawmill offcuts using low-power wood size reduction machines (WSRMs), mainly due to changes in wood supply frequency. This results in relatively high proportions of idling time. Fuel consumption and associated exhaust emissions of WSRMs with combustion engines can be reduced by using innovative drive unit control systems during idling. The objective of the research was to determine the effects of two speed control systems on the fuel consumption and exhaust emissions of a WSRM with a two-cylinder cutting mechanisms driven by a small 9.5 kW spark ignition engine. Speed control system A (commercially available) had a substantially higher rotational speed than system B (an innovative, adaptive solution subject to patent application No. P433586). Pine (Pinus sylvestris L.) wood sawmill offcuts (average cross-sectional area, length and water content: 25×40 mm, 3000 mm and ca. 12, respectively) were used in system tests at a feed rate of ca. 5 pieces min-1. Material of this size is typically processed by such machines. Operating conditions were monitored by recording the rotational speed and torque. Emissions of harmful exhaust compounds–carbon monoxide (CO), carbon dioxide (CO2), hydrocarbons (HC), and nitrogen oxides (NOx) – were recorded using a portable emission measurement system. Fuel consumption values were also calculated from the data. The following effects were observed: application of innovative system B resulted in 33% lower fuel consumption, as well as 30%, 37% and 33% lower CO, CO2 and NOx emissions, respectively, than system A, but at the same time 290% higher HC emissions were registered. In operating conditions with higher proportions of idling time, solution B provides even higher reductions in fuel consumption and exhaust emissions.

Road traffic is a common phenomenon in cities, and all urban road users suffer its negative effects. Therefore, the subject of this article is a comparative analysis of exhaust emissions of toxic compounds and operating parameters of two-wheeled vehicles measured in real operating conditions. The comparison applies to two drive cycles: in the first - the vehicle was traveling in standard city traffic (without using the bus lanes), while in the second - the vehicle travelled on bus lanes whenever those were available. Such analysis made it possible to assess the ecological usefulness of bus lanes by assessing the exhaust emissions and the travel time of the test vehicle. For this purpose, an analysis of the exhaust emission values in time was done for gaseous compounds (HC, CO, CO2, NOx) from a scooter equipped with a 125 cm3 displacement engine with a maximum power of 9 kW. The tests were carried out in real operating conditions in the city of Poznań. The route has been chosen so that it consists of roads with a number of bus lanes. AXIONR/S+ mobile apparatus belonging to the PEMS (Portable Emissions Measurement Systems) group was used in the research. The device is one of the most modern measuring instruments, where the entire device is a suitcase weighing only 18 kg containing two analyzers for measuring concentrations of both gaseous and solid exhaust components

Road transport holds for the largest share in the freight transport sector in Europe. This work is carried out by heavy vehicles of various types. It is assumed that, in principle, transport should take place on the main road connections, such as motorways or national roads. Their share in the polish road infrastructure is not dominant. Rural and communal roads roads are the most prevalent. This fact formed the basis of the exhaust emissions and fuel consumption tests of heavy vehicles in real operating conditions. A set of vehicles (truck tractor with a semi-trailer) meeting the Euro V emission norm, transporting a load of 24,800 kg, was selected for the tests. The research was carried out on an non-urban route, the test route length was 22 km. A mobile Semtech DS instrument was used, which was used to measure the exhaust emissions. Based on the obtained results, the emission characteristics were determined in relation to the operating parameters of the vehicles drive system. Road emission, specific emission and fuel consumption values were also calculated.

The article presents emission test results comparison carried out on a dynamic engine dynamometer. Parameters were recorded during a drive made in accordance with the requirements of the RDE. Test bench allowed to determine the particle mass and number emission in the repetitive engine operation conditions. One of three used elements wan an OEM solution from one of particulate filters producers, the other was intended for use in original systems, the third was a custom product. The highest efficiency of particulate filtration was demonstrated by the last filter, which was adapted to the engine.

W artykule zaprezentowano badania i analizę wskaźników ekologicznych dwóch ciągników szynowo-drogowych zrealizowane podczas rzeczywistej eksploatacji. Warunki testów i konstrukcje pojazdów charakteryzowały się zbliżonymi parametrami, przy czym obiekty spełniały odmienne normy emisji spalin: Stage IIIB i Stage IV. W badaniach zastosowano aparaturę z grupy PEMS. W analizie wskaźników ekologicznych wyznaczono jednostkową emisję szkodliwych związków gazowych i cząstek stałych. Uzupełnienie stanowi ocena wskaźników toksyczności, będących odniesieniem poszczególnych związków do emisji CO2. Korzystniejsze charakterystyki ekologiczne uzyskał pojazd spełniający nowszą normę emisji spalin, co wynikało przede wszystkim z zastosowania w jego konstrukcji zaawansowanych układów oczyszczania spalin.

The subject of this article is the analysis of the current state of legislation regarding the exhaust emissions from two-wheeled vehicles. Regulations and emission limits have been analyzed and compared for different areas of the world. What’s more, the review of the legal provisions includes an individual approach to specific categories of two-wheeled vehicles. The study also describes research and exhaust emission measurement methods from mopeds and motorcycles both in laboratory conditions and in actual operation. The methods were evaluated in the aspect of future emission requirements and trends. In addition, emissivity measurements results in real operating conditions obtained in the Poznań agglomeration with the use of motorcycle units were discussed and analyzed. The values of road emissions of all toxic compounds limited by legislators have been compared with emission standards.

The subject of the article is proposed proprietary M toxicity indicator, which is based on the assumption that CO2 emissions are a measure of the correctness of the combustion process. For this purpose, gaseous exhaust compounds such as hydrocarbons, nitrogen oxides, carbon monoxide and carbon dioxide were measured and analyzed. The test object was a motorcycle, equipped with an gasoline engine with a displacement of 0.7 dm3 and a maximum power of 55 kW. The tests were carried out using the PEMS (Portable Emissions Measurement System) AxionR/S+. The exhaust emissions measurement was done in line with the WMTC (World Motorcycles Test Cycle) certification test, dedicated to vehicles in this category. The test consists of three parts, each of them lasts 600 seconds and has a different maximum speed value. The test was performed on a single-roller chassis dynamometer, designed for testing two-wheeled vehicles. The toxicity indicators and rotation speed results were presented as a function of time.

The development and operation of road infrastructure requires machines and equipment driven by low-powered internal combustion engines. The authors of this paper examined five small spark-ignition engines. They used the most popular commercial design on the market, the Lifan GX 390, with a carburettor power system, and another commercial power unit with the most innovative power system, the Honda iGX 390, characterised by an electronically controlled carburettor flap. The remaining three tested constructions are proprietary solutions modernising the design of the Lifan GX 390 engine. The first is the application of an electronic injection and ignition system powered by gasoline, the second and third are systems powered by alternative fuels. Emissions tests were conducted under identical operating conditions on an engine dynamometer coinciding with European Union guidelines (Regulation 2016/1628/EU).The results of the tests showed that innovative solutions in most cases reduced CO,CO2, and HC emissions while increasing NOx compounds.

The subject of this article is the analysis of the particle number and mass road emission from a hybrid vehicle in real operating conditions. Additionally, the operating conditions of the tested vehicle and engine were also analyzed. To this end, particulate emissions and performance tests were carried out from a light hybrid vehicle, equipped with a 77 kW engine with a displacement of 1.58 dm3. The tests were conducted in real traffic conditions, following the standard RDE (Real Driving Emission) procedure. The test was performed within the Poznań agglomeration, the route included roads with different maxi-mum speed limits. The research involved the use of mobile measuring equipment, belonging to the PEMS (Portable Emissions Measurement System) group, which included equipment such as: SEMTECH DS, AVL MSS (Micro Soot Sensor) and EEPS 3090 (Engine Exhaust Particle Sizer). The results obtained have been referred to the vehicle exhaust emission limit values in accordance with the Euro 6 norm.

The projected increase in the availability of gaseous fuels by growing popularity of household natural gas (NG) filling stations and the increase in the production of gaseous biogas-derived fuels is conducive to an increase in the use of NG fuel. Currently, natural gas in various forms (compressed natural gas (CNG), liquefied natural gas (LNG)) is popular in maritime, rail and road transport. A new direction of natural gas application may be non-road mobile machines powered by a small spark-ignition engine (SI). The use of these engines in the wood chippers can cause the reduction of machine costs and emissions of harmful exhaust gases. In addition, plant material chippers intended for composting in bio-gas plants can be driven by the gas they are used to produce. The biogas can be purified to bio-methane to meet natural gas quality standards. The article presents the design of the natural gas supply system, which is an upgrade of the Lifan GX 390 combustion engine spark ignition engine (Four-stroke, OHV (over head valve) with a maximum power of 9.56 kW), which is a common representative of small gasoline engines. The engine is mounted in a cylindrical chipper designed for shredding branches with a maximum diameter of up to 100 mm, which is a typical machine used for cleaning work in urban areas. The engine powered by CNG and traditionally gasoline has been tested in real working conditions, when shredding cherry plum (Prunus cerasifera Ehrh. Beitr. Naturk. 4:17. 1789 (Gartenkalender4:189&ndash, 204. 1784)). Their diameter was ca. 80 mm, 3-metere-long, and humidity content ca. 25%. The systems were tested under the same actual operating conditions, the average power generated by the drives during shredding is about 0.69 kW. Based on the recorded results, it was found that the CNG-fuelled engine was characterized by nitrogen oxides (NOx) emissions higher by 45%. The other effects of CNG were a reduction in carbon dioxide (CO2), carbon monoxide (CO) and hydrocarbon (HC) emissions of about 81%, 26% and 57%, respectively. Additionally, the use of CNG reduced fuel consumption by 31% and hourly estimated machine operating costs resulting from fuel costs by 53% (for average fuel price in Poland: gasoline: 0.99 EUR/L and CNG: 0.71 EUR/m3 on 08 November 2020). The modernization performed by the authors ensured the work of the drive unit during shredding, closer to the value of stoichiometric mixtures. The average (AVG) value of the air fuel ratio (AFR) for CNG was enriched by 1.2% (AVG AFR was 17), while for the gasoline engine the mixture was more enriched by 4.8% (AVG AFR was 14). The operation of spark-ignition (SI) combustion engines is most advantageous when burning stoichiometric mixtures due to the cooperation with exhaust aftertreatment systems (e.g., three-function catalytic converter). A system powered by CNG may be beneficial in systems adapting to operating conditions, used in low-power shredding machines, whose problem is increased HC emissions, and CNG combustion may reduce them. The developed system does not exceed the emission standards applicable in the European Union. For CO emissions expressed in g/kWh, it was about 95% lower than the permissible value, and HC + NOx emissions were 85% lower. This suggests that the use of the fuel in question may contribute to tightening up the permissible emission regulations for non-road machinery.

This work determines the effect of the addition of various amounts of vanadium oxide on the work of a cell built from a hybrid VxOy-TiO2-rGO system in a lithium-ion cell. Moreover, a new method based on solvothermal chemistry is proposed for the creation of a new type of composite material combining reduced graphene, vanadium oxide and crystalline anatase. The satisfactory electrochemical properties of VxOy-TiO2-rGO hybrids can be attributed to the perfect matching of the morphology and structure of VxOy-TiO2 and rGO. In addition, it is also responsible for the partial transfer of electrons from rGO to VxOy-TiO2, which increases the synergistic interaction of the VxOy-TiO2-rGO hybrid to the reversible storage of lithium. In addition a full cell was created LiFePO4/VxOy-TiO2-rGO. The cell showed good cyclability while providing a capacity of 120 mAh g&minus, 1.

Analysis of the energy balance for an exhaust system of a diesel engine fit with an automotive thermoelectric generator (ATEG) of our own design has been carried out. A special measurement system and dedicated software were developed to measure the power generated by the modules. The research object was a 1.3-l small diesel engine with power output of 66 kW. The tests were carried out on a dynamic engine test bed that allows reproduction of an actual driving cycle expressed as a function V = f(t), simulating drivetrain (clutch, transmission) operating characteristics, vehicle geometrical parameters, and driver behavior. Measurements of exhaust gas thermodynamic parameters (temperature, pressure, and mass flow) as well as the voltage and current generated by the thermoelectric modules were performed during tests of our own design. Based on the results obtained, the flow of exhaust gas energy in the entire exhaust system was determined along with the ATEG power output. The ideal area of the exhaust system for location of the ATEG was defined to ensure the highest thermal energy recovery efficiency.

The article discusses the results of tests carried out under real operating conditions, based on which a custom test for road-rail vehicles was developed. The proposed test reflects the working conditions in which road-rail vehicles are used. The measurements were performed for a vehicle equipped with an internal combustion engine during five stages of operation. Measuring cycles included driving on a paved road, rolling on tracks and running on a track without load, with a load of 90 tons and with a load of 140 tons. The article compares the legislative guidelines with actual operation, thanks to which guidelines for the road-rail test for assessing the exhaust emission of harmful gases were developed. Based on the recorded data, a test proposal was described, taking into account the operating time share during the test, the average speed of travel and the duration of the test cycle. In addition, guidelines on the test procedure in the proposed test are discussed.

The subject of the article is the exhaust emission analysis of harmful gases from an two-wheeled urban motor vehicle in real operating conditions. For this purpose, characteristics of ecological indicators of compounds such as hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2) and nitrogen oxides (NOx) were presented. The tests were carried out on a two-wheeled urban vehicle, equipped with an engine with a stroke volume of 49 cm3 and a maximum power of 2.5 kW. What's more, the operating parameters of a moped registered during the test were also analyzed. The measurements were performed in real operating conditions in the Poznań agglomeration. The designated route included streets in the city center, and the maximum permissible speed did not exceed 50 km/h. The AXION R/S+ mobile apparatus belonging to the PEMS (Portable Emissions Measurement Systems) group was used for the research. The device is one of the most modern measuring instruments, enabling the measurement of concentrations and emissions of both gaseous and solid exhaust components. What is more, the obtained results of road emissions of harmful compounds were referred to the limit value of the exhaust emission norms, which the tested vehicle is expected to meet (Euro 3). The results indicated that the limit value for carbon monoxide was exceeded by 52%.

The paper presents the investigations of exhaust emissions under actual operation of two rail vehicles: a track geometry vehicle and a clearance vehicle. The environmental assessment of this type of objects is difficult due to the necessity of adapting the measurement equipment and meeting the safety requirements during the tests (particularly regarding the distance from the overhead electrical lines). The authors have proposed and developed a unique research methodology, based on which a detailed exhaust emissions analysis (CO, HC, NOx, and PM) was carried out. The complex assessment included the unit and on-track exhaust emissions. In the analyses, the authors also included the operating conditions of the powertrains of the tested machinery. The obtained environmental indexes were referred to the homologation standards, according to which the vehicles were approved for operation. Due to the nature of operation of the tested vehicles, the authors carried out a comprehensive environmental assessment in the daily and annual approach as well as in the aspect of their operation as combined vehicles, which is a novel approach to the assessment of the environmental performance of this type of objects.

The paper describes the analyses of the exhaust emissions from a city scooter performed under actual operating conditions. The measurements of the exhaust emissions were performed for CO2/fuel consumption, CO, HC and NOx. The investigations were carried out in actual traffic of high congestion in Poznan (Poland) in a driving cycle of the length of 7.35 km. The analyses were performed on a scooter fitted with a 125 cc engine with a start-stop system. The performed analyses revealed that the actual emissions of CO and HC were greater by 57% and 4%, respectively for the scooter with the start-stop system enabled, while the emission of NOx decreased by 10%. The application of the start-stop system contributed to the reduction of the fuel consumption/CO2 emission by approx. 12%. Large differences between the emission in real operating conditions and the Euro 4 emission standards have been obtained.

At the beginning of the twenty-first century, one of the major challenges of humanity was to reduce the negative effects of civilization development. Besides the engines used in road vehicles there is a large group of engines for non-road applications. This group includes motor propelled vehicles not used on the road NRMM (Non-Road Mobile Machinery). Engines of these vehicles, among all of the non-road applications, are characterized by very specific working conditions that do not allow for them to be qualified for propulsion engines. The main problem with these vehicles is the particulate matter and nitrogen oxides emission. Rail vehicles operating conditions these requirements take by the similar way, as having a wide range of rolling stock markedly alters the environmental impact of these vehicles. Thus it becomes necessary to consider the issue of the method of evaluation of engine emissions in rail vehicles in terms of their actual operating conditions. Thus, efforts to assess the actual level of emissivity for rail vehicles and attempts to improve it are necessary and justified.

We have analyzed the increase of the overall efficiency of a spark ignition engine through energy recovery following the application of an automotive thermoelectric generator (ATEG) of our own design. The design of the generator was developed following emission investigations during vehicle driving under city traffic conditions. The measurement points were defined by actual operation conditions (engine speed and load), subsequently reproduced on an engine dynamometer. Both the vehicle used in the on-road tests and the engine dynamometer were fit with the same, downsized spark ignition engine (with high effective power-to-displacement ratio). The thermodynamic parameters of the exhaust gases (temperature and exhaust gas mass flow) were measured on the engine testbed, along with the fuel consumption and electric current generated by the thermoelectric modules. On this basis, the power of the ATEG and its impact on overall engine efficiency were determined.

Due to the growing demand for traditionally sourced fossil fuels such as oil or natural gas, it became necessary to search for new unconventional sources of these raw materials. The latest results of research work targeted the exploration and exploitation of resources of yet another type of fuel – shale gas. According to estimates, Poland alone may have reserves of 5.3 billion cubic meters of natural gas, accumulated in non-conventional sources. This potential can be used in many sectors of the economy, including in transport. Thus, it became reasonable to consider the use of natural gas as an alternative power source for vehicles. The article presents the results of emissions from public buses powered by diesel fuel and compressed natural gas. The study was conducted in real traffic conditions on a regular bus line in Poznan. The measurement of toxic exhaust elements was conducted with the use of a mobile measuring system of exhaust gas analyzers PEMS (Portable Emissions Measurement System). The data obtained were used to determine the average emissions of individual components. Based on the obtained values it can be concluded that the use of different types of fuels to drive public transport vehicles leads to a reduction of air pollutants and thus to improvement in the quality of life in the city.

This article presents investigations of fuel consumption and CO2 emission of a farm tractor operating with a cultivator. The cultivator has been designed to operate at greater speeds of up to 15 km/h. During the tests, the tractor operated with different speeds, which influenced the fuel consumption and the time of operation. An increase in the cruising speed resulted in greater fuel consumption and a reduced time of operation. A fuel consumption curve was determined depending on the tractor speed. At the same time, the authors assessed the quality of the cultivation through soil analysis after the cultivation. The fuel consumption was measured with the carbon balance method – the most accurate method available. Such measurements were performed by the Portable Emission Measurement System (PEMS) equipment. The investigations utilizing the PEMS equipment enable measurements of the exhaust emissions under actual operating conditions, during fieldwork. The methodology used in the research is the most accurate and most reliable one currently available. It takes into account all of the variables of actual operation. This method is a state-of-the-art achievement in exhaust emissions measurement and has great potential. It may be successfully used for research related to assessment of energy consumption of farm tractors depending on the analyzed factors, e.g. type of soil, design of tools, and method of fieldwork. The performed tests allowed formulating conclusions related to the influence of the speed of the farm tractor with the cultivator on fuel consumption and emission of CO2. From the test, it follows that upon reaching a certain operating speed the increment of the fuel consumption is getting smaller while the time efficiency increases. The authors also observed that the above did not have impact on the quality of the cultivation. The presented results of the investigations and their analysis confirm the usefulness of the applied methodology in the assessment of energy consumption of farm tractors and machines during fieldwork operation.

The use of alternative fuels is a contemporary trend in science aimed at the protection of non-renewable resources, reducing the negative impact on people and reducing the negative impact on the natural environment. Liquefied petroleum gas (LPG) is an alternative fuel within the meaning of the European Union Directive (2014/94/UE), as it is an alternative for energy sources derived from crude oil. The use of LPG fuel in low-power internal combustion engines is one of the currently developed scientific research directions. It results from the possibility of limiting air pollutant emissions compared to the commonly used gasoline and the lower cost of this fuel in many countries. By &ldquo, gasoline 95&rdquo, the Authors mean non-lead petrol as a flammable liquid that is used primarily as a fuel in most spark-ignited internal combustion engines, whereas 95 is an octane rating (octane number). This article presents the results of research on fuel consumption, toxic exhaust gas emission, and operating costs of a woodchipper used for shredding branches with a diameter of up to 100 mm in real working conditions. The woodchipper, powered by a 9.5 kW internal combustion engine, fueled by gasoline and LPG was tested. Liberal regulations of the European Union (Regulation 2016/1628/EU) on the emission of harmful exhaust compounds from small spark-ignition engines (up to 19 kW) and non-road applications contribute to the low technical advancement level of these engines. The authors researched a relatively simple and cheap LPG fueling system, as in their opinion, such a system has the best chance of being implemented for use. In the study, the branches of cherry plum were shredded (Prunus cerasiferaEhrh. Beitr. Naturk. 4:17. 1789 (Gartenkalender4:189-204. 1784)). Their diameter was ca. 80 mm, length 3 m, and moisture content ca. 25%. The system was tested during the shredding of the branches in real working conditions (the frequency of supplying the branches about 4 min&minus, 1 and the mass productivity of about 0.73 t/h). Based on the recorded results, it was found that the LPG fueled engine was characterized by higher carbon monoxide (CO) and nitrogen oxides (NOx) emissions by 22% and 27%, respectively. A positive effect of using LPG was the reduction of fuel consumption by 28% and carbon dioxide (CO2) and hydrocarbons (HC) emissions by 37% and 83%, respectively. The results of the research show that the use of alternative fuels can bring benefits in terms of CO2 and HC emissions, but at the same time be characterized by an increase in CO and NOx emissions. Further research should be conducted on innovative alternative fuel supply systems, such as in the automotive industry. At the same time, legislators should limit the use of low-quality fuel supply systems with the limits of pollutant emissions in exhaust gases, contributing to the development and economic competitiveness of new fuel injection systems.

This paper discusses the determination of fuel consumption and exhaust gas emissions when shredding branches in urban areas. It aimed to determine the hourly emission of exhaust gases to the atmosphere during such work and to identify the designs that can reduce it. The research was carried out with a cylinder woodchipper driven by a low-power (9.5 kW) combustion engine. There were three configurations of the tested drive unit: The factory setting (A) with a carburettor fuel supply system, modernized by us to include an electronic injection system (B). This system (B) was expanded with an adaptation system patented by the authors (P. 423369), thus creating the third configuration (C). The research was carried out when shredding cherry plum (Prunus cerasifera Ehrh. Beitr. Naturk. 4:17. 1789 (Gartenkalender 4:189-204. 1784)) branches with a diameter of 80 mm, which presented a large load for the machine. The machine was operated by one experienced operator. The average operating conditions during the tests were as follows: Branch delivery frequency of about 4 min&minus, 1 and mass flow rate of about 0.72 t h&minus, 1. During the tests with the use of PEMS (portable emissions measurement system, here Axion RS from Global MRV), we analyzed the emissions of compounds, such as CO, CO2, HC, and NOx, and determined the fuel consumption based on the carbon balance. The research showed that the use of an injection system (B) reduced fuel consumption from 1.38 to 1.29 l h&minus, 1 (by 6.7%) when compared to the carburettor system (A). Modernization of the injection system (B) with an adaptive system (C) reduced fuel consumption from 1.38 to 0.91 l h&minus, 1 (by 34%) when compared to the carburettor system (A). An hour of shredding with a cylinder chopper emits the following amounts of flue gases: design A (HC 0.013 kg h&minus, 1, CO 0.24 kg h&minus, CO2 2.91 kg h&minus, NOx 0.0036 kg h&minus, 1), design B (HC 0.0061 kg h&minus, CO 0.20 kg h&minus, CO2 2.77 kg h&minus, NOx 0.0038 kg h&minus, 1), and design C (HC 0.017 kg h&minus, CO 0.22 kg h&minus, CO2 1.79 kg h&minus, NOx 0.0030 kg h&minus, 1). The adaptive system entails significant reductions in non-HC emissions, which indicates that the system needs to be improved with respect to fuel-air mixture control for its enrichment of the low-to-high-speed change. The admissible emission limits for harmful compounds in exhaust gas for the tested group of propulsion units are in accordance with the provisions in force in the European Union from 2019 for the tested propulsion units during operation, with a full CO load about 6100 g h&minus, 1 and HC + NOx about 80 g h&minus, 1. The tested propulsion units emitted significantly less pollution under real operating conditions (because they did not work under full load throughout the entire test sample).