In Poland, existing barrages are characterized by relatively high flow and low head, which is challenging for the effective utilization of theoretical watercourse power. The paper presents the impact of the minimum head of the hydro sets on the annual electricity production of small hydropower plants at low-head locations for two types of water turbines: Archimedes and Kaplan turbines. A developed mathematical model was used to simulate energy yield from Archimedes and Kaplan turbines for a given value of the minimum technical head, depending on the number of installed hydro sets. For economic analysis purposes, the levelized cost of electricity (LCOE) and net present value (NPV) indicators were calculated. The conducted research allowed for comparing Archimedes and Kaplan’s turbine operating conditions and how the minimum head parameter influences their electricity production and utilization time. As concluded in the results, the influence of minimum head in energy production is more distinct for the Archimedes screw technology than for the Kaplan turbine. The research shows that the decrease in energy production associated with the hydro unit’s minimum head parameter is from 0% to 30% for Kaplan, and it is 6% to 52% for Archimedes turbines.

E3S Web of Conferences, open access proceedings in environment, energy and earth sciences

Today, the increasing amount of waste is a growing ecological and financial problem. Another issue is the need to limit the share of controllable sources powered by fossil fuels. A hybrid generation system (HGS) is proposed to solve both problems. The system consists of renewable energy sources (RES) and a waste gasification system. Contrary to many papers, it is proposed to include syngas storage and use gas turbines as balancing sources. The HGS was modeled, and electricity generation, capacity factors, and efficiencies were calculated. The economic (LCOE and PP) and environmental parameters (CO₂ emission and reduction) were analyzed and calculated for different RES capacities. The results show that the proposed HGS covered 45.7–80% of municipal demand. The HGS was characterized by high CO₂ emissions, due to the low efficiency of gasification-gas turbine installation and the need to compress syngas. However, the HGS can be environmentally beneficial due to the reduction in waste disposal in landfills. The LCOE was EUR 174–191 with a minimum at the RES capacity of 14 MW. Any change in waste disposal costs and emission allowances would cause significant changes in the LCOE. It was found that it can be beneficial to use a gasification system as a balancing source in a HGS.

The purpose of this study is to compare the energy performance characteristics of two small modular reactor (SMR) technologies, the AP300 and the BWRX-300, under conditions of simultaneous electricity and heat production. Mathematical models of both systems were developed, covering the steam–water cycle, the turbine and the heat recovery system. The analysis was carried out for a heat output range of 50–500 MW_t, under identical heat utilisation conditions. The gross and net electrical power, in-house plant consumption, electrical, thermal and total efficiency, unit steam consumption and the cogeneration index were assessed. The symmetric percentage difference (PD) was used for a quantitative comparison of the characteristics. The results showed that the BWRX-300 has lower in-house plant consumption, whilst the AP300 has lower unit steam consumption for electricity generation. For this indicator, the PD value ranges from 15.77% to 31.08%, with an average of 22.21%. Furthermore, it was shown that the impact of reactor technology on cogeneration characteristics depends on the parameter under analysis. The largest differences relate to parameters associated with the conversion of heat into electricity, whilst characteristics related to heat production show a higher degree of consistency.