The critical role of energy in contemporary life and the environmental challenges associated with its production imply the need for research and exploration of its novel resources. The present review paper emphasizes the continuous exploitation of non-renewable energy sources, suggesting the transition toward renewable energy sources, termed ‘green energy’, as a crucial step for sustainable development. The research methodology involves a comprehensive review of articles, statistical data analysis, and examination of databases. The main focus is biomass, a valuable resource for bioenergy and biopesticide production, highlighting not only its traditional diverse sources, such as agricultural waste and industrial residues, but also non-edible invasive alien plant species. This study explores the utilization of invasive alien species in circular economy practices, considering their role in bioenergy and biopesticide production. The potential conflict between bioproduct acquisition and food sector competition is discussed, along with the need for a shift in approaching non-edible biomass sources. The paper emphasizes the untapped potential of under-explored biomass resources and the necessity for policy alignment and public awareness. Species with a significant potential for these sustainable strategies include Acer negundo L., Ailanthus altisima (Mill.) Swingle., Amorpha fruticosa L., Elaengus angustifolia L., Falopia japonica (Houtt.) Ronse Decr., Hibiscus syriacus L., Koelreuteria paniculata Laxm., Paulownia tomentosa Siebold and Zucc., Partenocissus quenquefolia (L.) Planch., Rhus typhina L., Robinia pseudoacacia L. and Thuja orientalis L. In conclusion, the paper highlights the intertwined relationship between energy, environmental sustainability, and circular economy principles, providing insights into Serbia’s efforts and potential in adopting nature-based solutions for bioenergy and biopesticides acquisition.

The main aim of the article is to present the design of laboratory test equipment, which is appropriate for monitoring the efficiency of oil filters and the system for evaluating the technical life of engine oils in terms of possible extension of service intervals. The functionality of the designed laboratory test equipment for the filtration of motor oils was verified by a practical experiment with a verification measurement and assessment of the suitability of the hydraulic circuit elements and the designed sensing equipment. The laboratory equipment enables the testing of oil filters with different filtration capacity during simultaneous testing in two separate hydraulic circuits with differently contaminated engine oil, while it enables laboratory measurements to be performed while simulating operating conditions.

Power delivery efficiency shows how much engine power is used for a tractor drawbar. Eccentric traction is a factor influencing the power delivery efficiency of a wheeled tractor. It occurs as a consequence of the offset position of a tractor implement, that is, when the traction line of the tractor and resistance line of the implement are parallel and do not coincide. This paper presents research on the power delivery efficiency of wheeled tractors and its dependence on wheel slippage of central and eccentric drawbar forces on unplowed and plowed stubble. For this purpose, mathematical models and one algorithm were developed. The best power delivery efficiency of the tractor on both unplowed and plowed stubble surfaces was obtained with central drawbar force. Power delivery efficiency of the tractor on unplowed stubble decreased by 5.72% if eccentricity increased up to 0.16 m and by 12.33% if eccentricity increased up to 0.32 m. Power delivery efficiency of the tractor on plowed stubble decreased by 8.88% if eccentricity increased up to 0.16 m and decreased by 19.05% if eccentricity increased up to 0.32 m.

This article focuses on the properties of ecological energy carriers, which are used in agricultural and forestry technology. The aim of the article is to describe the degradation of the working fluid from the point of view of the atomic emission spectrometer, which is used for the purpose of monitoring contaminants and additive elements. The working fluid examined was Shell Naturelle HF-E 46, a universal ecological transmission–hydraulic fluid, which was tested on laboratory test equipment. The laboratory measurement was performed for 200 h, during which the gear hydraulic pump with external gearing was cyclically loaded according to the Vickers standard. The analysis of the transmission–hydraulic fluid was performed after every 50 working hours, where the analysis of the working fluid showed that there were no significant changes in the properties of the working fluid and fluid is suitable for work in agricultural and forestry machines operating in environmentally sensitive environments.

This paper presents a research on the noise intensity and vibrations in the cabin of a self-propelled machine with high clearance, Hidromatiks S-PST, designed for specific farming operations in crop growing. Noise inside the cabin was measured at operator's head level. In order to determine the intensity of "whole body vibrations" that the operators are exposed to while using the self-propelled machines, the vibrations were measured at the seat of the machine."Hand-arm vibrations" were measured at the steering wheel and control stick of the machine. The measurings were performed during travelling on different surfaces: asphalted road, dirt road, and furrows. The results of measured noise level indicated that the effective values obtained from the cabin of a self-propelled machine travelling over asphalted surface, dirt road and furrows were below the limit values of exposure to noise set by the Rulebook. The results showed that travelling of a self-propelled machine on asphalted road, dirt road and furrows had "whole body vibrations"and "hand-arm vibrations", i.e. Daily values of exposure to vibrations (A(8) (m/s2 )), far below the Daily limit values of exposure, and even below the Daily action values of exposure set by the Rulebook, for both types of vibrations. Such results obtained from measured level of noise and vibrations imply that the operators using self-propelled machinery Hidromatiks S-PT, are not in risk of damaging their health, which damages can be caused by noise and vibrations.