This paper presents the results of research on the energetic use of self-combusted hemp pellets and co-firing with pine pellets. The tests were carried out with the use of a boiler equipped with a Lester Projekt Company gasifying burner and an automatic fuel feeding system. The boiler is equipped with an additional heat exchanger that enables the simulation of any heat load. The experimental stand so built guaranteed to obtain results adequate to the real operating conditions. The research material consisted of pellets made of waste biomass of the Futura 75 sowing hemp and pine sawdust pellets. The experiment was carried out in five proportions by mass of mixtures of both fuels (C-hemp, P-pine): 0:100 (P100), 25:75 (C25/P75), 50:50 (C50/P50), 75:25 (C75/P25), 100:0 (C100). For each variant, the following were determined: effective boiler power, boiler energy balance, boiler energy efficiency, the volumetric composition of flue gas (carbon monoxide, carbon dioxide, hydrogen, sulfur dioxide, nitrous oxide), excess air coefficient and the dust content of particle matter—PM10, PM2.5. The heating value was also determined for hemp pellets and pine sawdust pellets, accordingly 17.34 and 19.87 MJ·kg⁻¹. The obtained test results were related both to the volume of exhaust gases leaving the boiler and to one kilowatt hour of heat produced. The obtained test results showed that the boiler fed with pine pellets achieved the highest thermal power (P100)—14.17 kW, while the smallest—hemp pellets (C100)—4.92 kW. The CO₂ emissivity increased with the addition of pine pellets, from 26.13 g (C100) to 112.36 g (P100) relating to 1 m³ and from 430.04 g (C100) to 616.46 g (C25/P75) relating to 1 kWh of heat. In terms of dust emissions, it was found that the combustion of hemp pellets and mixtures thereof is a little worse than that of pine pellets.

Purpose: This paper aims to assess the sustainability of energy generation systems in various European Union countries. It seeks to understand the diverse challenges and opportunities these countries face in transitioning to sustainable energy. Methodology: The study employs a multi-criteria decision analysis (MCDA) approach, considering economic, environmental, and social aspects. Data from various databases, including Eurostat, the International Energy Agency, and the World Bank, were analyzed. Results: The results reveal significant variations in sustainability performance across different countries and regions. With strong policy support and high public awareness, Scandinavian countries generally performed well across all sustainability indicators. In contrast, Eastern European countries faced more challenges due to their heavy reliance on fossil fuels. Theoretical Contribution: This study contributes to the ongoing discourse on sustainable energy by providing a comprehensive assessment of the sustainability of energy generation systems. It underscores the complex and multifaceted nature of sustainability and the various factors that influence it. Practical Implications: The findings provide valuable insights for policymakers and energy providers. They highlight the importance of policy support, public awareness, and acceptance in promoting sustainable energy. They also underscore the need for continued efforts and interventions to address the challenges faced by countries heavily reliant on fossil fuels.

Biogas production by fermentation is a relatively low-cost and simple method for the transformation of a substrate into an energy carrier with a wide range of possible applications. The aim of this study was to determine the potential of Arthrospira platensis biomass as a source of bioenergy produced during anaerobic digestion (AD). The studies were carried out on a fractional-technical scale. Biogas yield and composition were analyzed as a function of the amount of biomass subjected to anaerobic digestion, the substrate dosing frequency in the digester and the use of biomass pre-hydrolysis in the mixing compartment. The energy efficiency of the process was also compared for each sample. In addition, a biomass conversion power index was developed and determined. It was found that A. platensis biomass had significant energy potential, and the amount of biogas obtained and its calorific value changed depending on the applied treatments. The maximum cumulative biogas production was 505 L kg⁻¹ volatile solids (VS), while the maximum average methane (CH₄) content was 67.32%. A two-fold increase in the organic loading rate from 1 g VS·L⁻¹ volatile solids (VS) to 2 g VS·L⁻¹ had a positive effect on methane concentration. The highest energy efficiency of the AD process was obtained for 2 g VS·L⁻¹, with a single feedstock input into the digester, in a single-stage process (2/s/-), while the highest conversion power ratio was for a feedstock of 1 g VS·L⁻¹, under the same process conditions (1/s/-). Moreover, the energy efficiency of the microalgae fermentation process obtained in the study is higher compared to conventional substrates used in biogas plants. This energy analysis can support the selection of cogeneration power engines in a biogas plant and help to determine the potential output of the biogas plant, especially with varying energy and heat demand.

A laboratory research was carried out to examine the impact of humic acids (HA) on swelling and germination of ‘Nawiko’ and ‘Progres’ soybean seeds under salt stress (50 mM dm−3 NaCl) and water deficit stress (−0.5 MPa) induced by polyethylene glycol (PEG) 6000. HA in the form of a dry preparation was obtained from peat using the IHSS method. Tests on swelling and germination used non-fractionate preparation (NFHA) and two of its molecular fractions obtained using Millipore filters with a 30 kDa cut-off point. This enabled us to obtain two fractions: with a higher molecular weight, above 30 kDa (HMHA), and a lower molecular weight, below 30 kDa (LMHA). The carbon concentration in HA solutions, used in all tests, was 0.005 g CHA dm−3. The results showed that HA mitigate the negative impact of salinity and water deficit on swelling and germination of soybean seeds.

This article attempts to identify and analyze the factors influencing the shaping of regional energy policy in the West Pomeranian Voivodeship, with particular emphasis on the potential for the development of renewable energy based on biomass. The aim of the publication is to determine the potential for the development of biomass resources, taking into account the criteria of sustainable development, i.e. economic, ecological and social aspects. So far, few researchers have dealt with this subject in a comprehensive way, and so far there has been a lack of detailed research on the potential of biomass in the West Pomeranian Region. The presented analyses are an important contribution to the development of knowledge about alternative energy sources in the energy sector. The research material used in the article comes from various sources, both domestic and foreign, including empirical data from scientific institutes of energy and fuels and regional institutions dealing with energy.

In light of global challenges such as the war in Ukraine and the depletion of fossil fuel resources, it is essential to explore sustainable energy solutions. Hybrid energy systems represent a potential solution, offering energy independence to urban housing estates and reducing CO₂ emissions. This article aims to explore the feasibility of integrating photovoltaic systems (utilizing vacuum collectors) and combined utilities (system heat and electricity) in a hybrid setup, leveraging existing technical infrastructure with necessary modifications. A key aspect is to perform calculations on the amount of heat and electricity generated from these systems. The study analyzes the demand for heat and electricity among consumers compared to the estimated production from renewable sources. Calculations also include the potential energy savings and CO₂ emission reductions achievable through the proposed solutions. The findings indicate that hybrid photovoltaic systems with heat storage could effectively address energy issues in urban housing estates, given adequate support and community involvement. The innovative methodology employed in this study encompasses both analytical and experimental research approaches. The analysis employs advanced statistical techniques and data integration to enhance understanding of the phenomena studied, while the experimental research provides robust results through controlled variable manipulation and precise measurement tools, thereby verifying the study’s objectives.