Ing. Lukáš Janota

Intentionally planted biomass is one of the important possible sources for biomethane production. The production cost of biomass plays a key role in both a farmer's decision to grow it and the efficiency of biomethane production. Unlike conventional agricultural crops, biomass grown for biogas or biomethane plants does not have a direct market price. The paper presents a methodology for determining the limit of biomass production price based on modelling lost revenue from planting conventional crops over the lifetime of the biogas or biomethane plant, considering local agrotechnical practices and soil and climatic conditions. The application of the methodology is demonstrated by providing maize biomass for a reference biogas plant and conditions of the Czech Republic. The production price of maize silage is in the range of 25.6–29.4 EUR/tFM for base line scenario of conventional crop prices. The increase in commodity prices in 2021 and 2022 leads to an increase in the biomass production price up to 34–43 EUR/tFM.

The article presents a proposal for a comprehensive methodology designed to increase the energy self-sufficiency and overall resilience of rural areas. The methodology aims to maximize the synergy and economic benefit of the agrovoltaic system with the cultivation of the energy crop Miscanthus x giganteus and its use for energy production in CHP sources within the local energy community. Primary data from Miscanthus x giganteus cultivation from long-term field trials and commercial plantations and initial agrovoltaic experiments were used. The analysed data show the high resistance and adaptability of Miscanthus x giganteus to climate change and confirm its expected long-term high yields of around 15 t DM ha(-1) y(-1) with a Higher Heating Value of 17-19 GJ t(-1). The application of the methodology to a case study in the Czech Republic shows a reduction in electricity consumption by more than 40% (2 GWh) and a reduction in thermal energy consumption by more than 15% (4 GWh). The technical-economic analysis shows the high potential, financial and non-financial benefits of local production of energy fuels from biomass as part of subsequent production and energy distribution in the agrovoltaic field.

This paper presents the methodology and findings of a comprehensive study that in the selected key time milestones (2030, 2040, 2050) assess the ongoing energy transformation and its impacts within the interconnected European electricity system and overall energy security. The study models the expected development of the installed capacities of individual types of energy sources, respecting the steps leading to meeting the EU's ambitious binding climate and energy goals, as well as individual countries’ national plans like development of RES or phase out of coal and nuclear power plants. The majority output of the complex methodology is the evaluation of the state of shortages or surpluses of electrical energy in the European electricity system in the selected key time milestones. The model outputs show that increasing integration of RES may cause higher requirements for maintaining the EU's energy security. The current most significant barriers to the fulfillment of climate and energy goals for maintaining the EU's energy security include not the lack of generation resources but the inflexibility of the electricity system and the lack of technologically and economically efficient seasonal accumulation. It will be essential to involve all types of technologies providing flexibility and all energy market participants, including households.

The article presents a proposal for a comprehensive methodology for the design of the process of local production of alternative energy fuel. The goal of the methodology is to ensure a local source of renewable fuel (biomass) for the needs of covering the supply of thermal energy to citizens in rural areas. In the first part, the methodology deals with the issue of sustainable cultivation of energy crops, namely short rotation coppice and its appropriate placement on soil blocks which are threatened by erosion or degraded by intensive agriculture. Subsequently, the local energy community independently produces alternative pellet biofuel, from the initial cultivation of young woody plants to the final production of ecological wood-based fuel with a calorific value of 16 MJ/ kg. The proposed innovative method of heat production leads to environmental benefits, energy savings, reduced payments for energy supply, and overall modernization of the technologies used. & COPY; 2023 The Authors. Published by Elsevier Ltd.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

This paper deals with an assessment of the steps taken and planned by the EU (European Union) to achieve its climate neutrality by 2050. Emphasis is placed on the reality of achieving RES (renewable energy sources) in total energy production in individual countries according to the required values for 2030. A detailed analysis of the previously set goals of penetration of RES and their historical fulfillment was performed. Furthermore, an evaluation of the planned shutdown of traditional combustion sources and the overall loss of constant production power, which keeps the energy system stable with a sufficient amount of standby power in real time is performed. In connection with these facts of the EU plans of the shift away from coal power plants and the nature of the intermittent electricity generation of the used renewable sources within the EU and the historical dynamics of the RES production capacities installation are evaluated.

The treatment and disposal of sewage sludge is one of the most important and critical issues of wastewater treatment plants. One option for sludge liquidation is the production of fuel in the form of pellets from mixed sewage and paper mill sludge. This study presents the results of the combustion of pelletized fuels, namely sewage and paper mill sludge, and their 2:1 and 4:1 blends in a fluidized bed combustor. The flue gas was analysed after reaching a steady state at bed temperatures of 700–800 °C. Commonly used flue gas cleaning is still necessary, especially for SO2; therefore, it is worth mentioning that the addition of paper mill sludge reduced the mercury concentration in the flue gas to limits acceptable in most EU countries. The analysis of ash after combustion showed that magnesium, potassium, calcium, chromium, copper, zinc, arsenic, and lead remained mostly in the ash after combustion, while all cadmium from all fuels used was transferred into the flue gas together with a substantial part of chlorine and mercury. The pellets containing both sewage and paper mill sludge can be used as an environmentally friendly alternative fuel for fluidised bed combustion. The levelized cost of this alternative fuel is at the same current price level as lignite. © 2022 by the authors.

The new Li-ion battery systems used in electric vehicles have an average capacity of 50 kWh and are expected to be discarded when they reach approximately 80% of their initial capacity, because they are considered to no longer be sufficient for traction purposes. Based on the official national future development scenarios and subsequent mathematical modeling of the number of electric vehicles (EVs), up to 400 GWh of storage capacity in discharged batteries will be available on the EU market by 2035. Therefore, since the batteries still have a considerable capacity after the end of their first life, they could be used in many stationary applications during their second life, such as support for renewables, flexibility, energy arbitrage, peak shaving, etc. Due to the high output power achieved in a short time, one of the most promising applications of these batteries are ancillary services. The study assesses the economic efficiency of the used batteries and presents several main scenarios depending on the likely future development of the interconnected EU regulatory energy market. The final results indicate that the best results of second-life batteries utilization lie in the provision of Frequency Containment Reserve Service, both from a technical and economic point of view. The internal rate of return fluctuates from 8% to 21% in the realistic scenario, and it supports the idea that such systems might be able to be in operation without any direct financial subsidies.