This paper investigates the environmental impacts and energy benefits of the cultivation of Miscanthus (Miscanthus × giganteus Greef et Deu.), in order to initiate its use in sustainable household heating in the Republic of Serbia. Based on the analysis of available data regarding the use of agricultural machinery in Serbia, a Miscanthus supply chain is constructed and examined in detail, scrutinizing all relevant operations—from planting of rhizomes to thermal energy production. Results of the life cycle assessment identify the briquetting process as the most environmentally burdensome operation due to high electricity consumption and low productivity. It is concluded that an average yield of 23.5 t dry matter (d.m.) year⁻¹ obtained from 1 ha of chernozem soil would have energy output:energy input (EO:EI) ratio of 51:1, and would release 365.5 gigajoules (GJ) of heat during combustion in a boiler. With this amount of energy, around 383 m² of a free-standing family house in Serbia can be heated annually. The same amount of energy is obtained by the combustion of 22 t of lignite or 23 t of wood logs. The substitution of lignite and wood with Miscanthus briquettes would lead to significant reduction of CO₂ equivalents (eq), SO₂ eq, P eq, N eq, 1,4 dichlorobenzene (1,4-DB) eq, Non-methane volatile organic compound (NMVOC), PM10 eq and U235 eq emissions. This designates Miscanthus as a more sustainable energy solution for household heating. In instances where more modern agricultural machinery is used, emission reduction is higher, except for CO₂ eq due to higher emission factors predicted for more powerful engines. Depending on Miscanthus’ annual yield, the replacement of set-aside land with Miscanthus plantations result in carbon (C) sequestration from 0.08 t C ha⁻¹ year⁻¹ to 0.91 t C ha⁻¹ year⁻¹. In a modern machinery scenario, C sequestration is only attainable when maximal Miscanthus yield is obtained. The combined use of machinery with different engine power is the best option for Miscanthus cultivation in Serbia.

For accelerating hypersonic vehicles, it is important to understand the effects of various factors on heat transfer deterioration. The heat transfer characteristics of supercritical n-decane with pyrolysis were numerically simulated inside a vertical tube. The effects of flow direction, mass-flow rate, heat flux, inlet temperature, and flight acceleration on the heat transfer characteristics were investigated. When the inlet temperature was relatively low or the fluid was decelerated vertically upward, a typical M-shaped velocity distribution was formed, indicating the heat transfer deterioration. Furthermore, the decrease in wall heat flux, as well as the increase in mass-flow rate, inlet temperature and flight acceleration in the same direction as the flow makes the heat transfer deterioration gradually disappear. Finally, a new relationship was established between the heat flux and the flight acceleration and inlet temperature to determine critical heat flux under which heat transfer deterioration developed in the upward flow.

In this paper ?well-to-pump? environmental analysis of pyrolytic diesel from Miscanthus gigantheus is performed. The average annual yield of Miscanthus from III-V year of cultivation on 1 ha of chernozem soil in Serbia (23.5 t) is considered as an input for the process. Two pyrolytic diesel pathways are considered: distributed pyrolytic pathway with external hydrogen production (from natural gas) and integrated pyrolytic pathway with internal hydrogen production (from pyrolytic oil). and are compared to a conventionally produced diesel pathway. The results of the analysis reveal that integrated-internal pyrolytic diesel pathway has lowest resources consumption and lowest pollutant emissions. Compared to conventionally produced diesel, integrated-internal pyrolysis pathway consumes 80% less of fossil fuels, and 92% more of renewables, has 90% lower global warming potential, 30% lower terrestrial acidification potential but 38% higher particulate matter formation potential. Compared to the distributed-external pathway, 88% less fossil fuels, and 36% less renewables are consumed in the integrated-internal pathway, global warming potential is 97% lower, terrestrial acidification is 20% lower, and particulate matter formation is 49% lower. Nevertheless, this pathway has high coal and hydroelectrical power consumption due to electricity production and high emissions of particulate matter, CO2, SOx, and N2O. Another drawback of this production pathway is the low yield of diesel obtained (38% lower than in distributed-external pathway). With this regard, it is still hard to designate production of diesel from fast pyrolysis of Miscanthus as a more environmentally friendly replacement of the conventional production diesel pathway.

This study proposes optimal supply chain models for agricultural biomass, focusing on straw and corn stalks. Four bioenergy chains, corn stalk pellets, corn stalk chips, straw bales, and straw pellets, were evaluated using multicriteria decision making tools and life cycle assessment. Key criteria included energy efficiency, investment costs, fuel production costs, and environmental impacts such as GHG emissions, acidification, eutrophication, and particulate matter formation. Results indicate that straw bales (L3) and corn stalk chips (L2) offer the most sustainable options, with straw bales demonstrating superior energy efficiency and lower environmental impacts. The VIKOR method, combined with the entropy weight method, identified straw bales as the optimal supply chain under various weighting scenarios. These findings provide actionable insights for sustainable bioenergy development and policy formulation.