Poland

The interaction of a shock wave with a specific angle or concave wall due to its reflection and focusing is a way to onset the detonation provided sufficiently strong shock wave. In this work we present numerical simulation results of the detonation initiation due to the shock reflection and focusing in a 90-degree wedge for mixtures of H2 and air. The code used was ddtFoam [1–3] that is a component of the larger OpenFOAM open-source CFD package of density-based code for solving the unsteady compressible Navier-Stokes equations. The numerical model represents the 2-D geometry of the experiments performed by Rudy [4]. The numerical results revealed three potential scenarios in the corner after reflection: shock wave reflection without ignition deflagrative ignition with intermediate transient regimes with a delayed transition to detonation in lagging combustion zone at around 1.8 mm from the apex of the wedge and ignition with an instantaneous transition to detonation with the formation of the detonation wave in the corner tip. In the experimental investigation the transition velocity for the stoichiometric mixture was approximately 715 m/s while in the numerical simulation the transition velocity for the stoichiometric mixture was 675.65 m/s 5.5% decrease in velocity.

This article presents the concept of green transformation of the coal mining sector. Pump stations that belong to Spółka Restrukturyzacji Kopal´n S.A. (SRK S.A. Bytom Poland) pump out approximately 100 million m3 of mine water annually. These pump stations protect neighboring mines and lower-lying areas from flooding and protect subsurface aquifers from contamination. The largest cost component of maintaining a pumping station is the expenditure for purchasing electricity. Investment towards renewable energy sources will reduce the environmental footprint of pumping station operation by reducing greenhouse gas emissions. The concept of liquidation of an exemplary mining site in the context of a circular economy by proposing the development/revitalization of a coal mine site is presented. This concept involves the construction of a complex consisting of photovoltaic farms combined with efficient energy storage in the form of green hydrogen produced by water electrolysis. For this purpose the potential of liquidated mining sites will be utilized including the use of pumped mine wastewater. This article is conceptual. In order to reach the stated objective a body of literature and legal regulations was analyzed and an empirical study was conducted. Various scenarios for the operation of mine pumping stations have been proposed. The options presented provide full or nearly full energy self-sufficiency of the proposed pumping station operation concept. The effect of applying any option for upgrading the pumping station could result in the creation of jobs that are alternatives to mining jobs and a guarantee of efficient asset management.

A transient pipeline flow model with gas composition tracking is solved for studying the operation of a natural gas pipeline under nonisothermal flow conditions in a hydrogen injection scenario. Two approaches to high-resolution pipeline flow modeling based on the WENO scheme are presented and compared with the implicit finite difference method. The high-resolution models are capable of capturing fast fluid transients and tracking the step changes in the composition of the transported mixture. The implicit method assumes the decoupling of the flow model components in order to enhance calculation efficiency. The validation of the composition tracking results against actual gas transmission pipeline indicates that both models exhibit good prediction performance with normalized root mean square errors of 0.406% and 1.48% respectively. Under nonisothermal flow conditions the prediction response of the reduced model against a high-resolution flow model with respect to the mass and energy linepack is at most 3.20%.

The article presents the application of the metalog family of probability distributions to predict the energy production of photovoltaic systems for the purpose of generating small amounts of green hydrogen in distributed systems. It can be used for transport purposes as well as to generate energy and heat for housing purposes. The monthly and daily amounts of energy produced by a photovoltaic system with a peak power of 6.15 kWp were analyzed using traditional statistical methods and the metalog probability distribution family. On this basis it is possible to calculate daily and monthly amounts of hydrogen produced with accuracy from the probability distribution. Probabilistic analysis of the instantaneous power generated by the photovoltaic system was used to determine the nominal power of the hydrogen electrolyzer. In order to use all the energy produced by the photovoltaic system to produce green hydrogen the use of a stationary energy storage device was proposed and its energy capacity was determined. The calculations contained in the article can be used to design home green hydrogen production systems and support the climate and energy transformation of small companies with a hydrogen demand of up to ¾ kg/day.

To reach climate neutrality by 2050 a goal that the European Union set itself it is necessary to change and modify the whole EU’s energy system through deep decarbonization and reduction of greenhouse-gas emissions. The study presents a current insight into the global energy-transition pathway based on the hydrogen energy industry chain. The paper provides a critical analysis of the role of clean hydrogen based on renewable energy sources (green hydrogen) and fossil-fuels-based hydrogen (blue hydrogen) in the development of a new hydrogen-based economy and the reduction of greenhouse-gas emissions. The actual status costs future directions and recommendations for low-carbon hydrogen development and commercial deployment are addressed. Additionally the integration of hydrogen production with CCUS technologies is presented.

Currently modern hydrogen technologies due to their low or zero emissions constitute one of the key elements of energy transformation and sustainable development. The growing interest in hydrogen is driven by the European climate policy aimed at limiting the use of fossil fuels for energy purposes. Although not all opinions regarding the technical and economic potential of hydrogen energy are positive many prepared forecasts and analyses show its prospective importance in several areas of the economy. The aim of this article is to provide a comprehensive review of modern materials current hydrogen technologies and strategies and show the opportunities problems and challenges Poland faces in the context of necessary energy transformation. The work describes the latest trends in the production transportation storage and use of hydrogen. The environmental social and economic aspects of the use of green hydrogen were discussed in addition to the challenges and expectations for the future in the field of hydrogen technologies. The main goals of the development of the hydrogen economy in Poland and the directions of actions necessary to achieve them were also presented. It was found that the existence of the EU CO2 emissions allowance trading system has a significant impact on the costs of hydrogen production. Furthermore the production of green hydrogen will become economically justified as the costs of energy obtained from renewable sources decrease and the costs of electrolysers decline. However the realisation of this vision depends on the progress of scientific research and technical innovations that will reduce the costs of hydrogen production. Government support mechanisms for the development of hydrogen infrastructure and technologies will also be of key importance.

To inject green hydrogen (H2) into the existing natural gas (NG) infrastructure is one way to decarbonize the European energy system. However asset readiness is necessary to be successful. Preliminary analysis and experimental results about the compatibility of hydrogen and natural gas mixtures (H2NG) with the actual gas grids make the scientific community confident about the feasibility. Nevertheless specific technical questions need more research. A significant topic of debate is the impact of H2NG mixtures on the performance of state-ofthe-art fiscal measuring devices which are essential for accurate billing. Identifying and addressing any potential degradation in their metrological performance due to H2NG is critical for decision-making. However the literature lacks data about the gas meters’ technologies currently installed in the NG grids such as a comprehensive overview of their readiness at different concentrations while data are fragmented among different sources. This paper addresses these gaps by analyzing the main characteristics and categorizing more than 20000 gas meters installed in THOTH2 project partners’ grids and by summarizing the performance of traditional technologies with H2NG mixtures and pure H2 based on literature review operators experience and manufacturers knowledge. Based on these insights recommendations are given to stakeholders on overcoming the identified barriers to facilitate a smooth transition.

This article presents a 3D model of a yellow hydrogen generation system that uses the electricity produced by a photovoltaic carport. The 3D models of all key system components were collected and their characteristics were described. Based on the design of the 3D model of the photovoltaic carport the amount of energy produced monthly was determined. These quantities were then applied to determine the production of low-emission hydrogen. In order to increase the amount of low-emission hydrogen produced the usage of a stationary energy storage facility was proposed. The Metalog family of probability distributions was adopted to develop a strategic model for low-emission hydrogen production. The hydrogen economy of a company that uses small amounts of hydrogen can be based on such a model. The 3D modeling and calculations show that it is possible to design a compact low-emission hydrogen generation system using rapid prototyping tools including the photovoltaic carport with an electrolyzer placed in the container and an energy storage facility. This is an effective solution for the climate and energy transition of companies with low hydrogen demand. In the analytical part the Metalog probability distribution family was employed to determine the amount of monthly energy produced by 6.3 kWp photovoltaic systems located in two European countries: Poland and Italy. Calculating the probability of producing specific amounts of hydrogen in two European countries is an answer to a frequently asked question: In which European countries will the production of low-emission hydrogen from photovoltaic systems be the most profitable? As a result of the calculations for the analyzed year 2023 in Poland and Italy specific answers were obtained regarding the probability of monthly energy generation and monthly hydrogen production. Many companies from Poland and Italy are taking part in the European competition to create hydrogen banks. Only those that offer low-emission hydrogen at the lowest prices will receive EU funding.

Green hydrogen production is expected to play a major role in the context of the shift towards sustainable energy stipulated in the Fit for 55 package. Green hydrogen and its derivatives have the capacity to act as effective energy storage vectors while fuel cell-powered vehicles will foster net-zero emission mobility. This study evaluates the potential of green hydrogen production in Power-to-Gas (P2G) systems operated in former mining sites where sand and gravel aggregate has been extracted from lakes and rivers under wet conditions (below the water table). The potential of hydrogen production was assessed for the selected administrative unit in Poland the West Pomerania province. Attention is given to the legal and organisational aspects of operating mining companies to identify the sites suitable for the installation of floating photovoltaic facilities by 2050. The method relies on the use of GIS tools which utilise geospatial data to identify potential sites for investments. Basing on the geospatial model and considering technical and organisational constraints the schedule was developed showing the potential availability of the site over time. Knowing the surface area of the water reservoir the installed power of the floating photovoltaic plant and the production capacity of the power generation facility and electrolysers the capacity of hydrogen production in the P2G system can be evaluated. It appears that by 2050 it should be feasible to produce green fuel in the P2G system to support a fleet of city buses for two of the largest urban agglomerations in the West Pomerania province. Simulations revealed that with a water coverage ratio increase and the planned growth of green hydrogen generation it should be feasible to produce fuel for net-zero emission urban mobility systems to power 200 buses by 2030 550 buses by 2040 and 900 buses by 2050 (for the bus models Maxi (40 seats) and Mega (60 seats)). The results of the research can significantly contribute to the development of projects focused on the production of green hydrogen in a decentralised system. The disclosure of potential and available locations over time can be compared with competitive solutions in terms of spatial planning environmental and societal impact and the economics of the undertaking.

According to the European Hydrogen Strategy hydrogen will solve many of the problems with energy storage for balancing variable renewable energy sources (RES) supply and demand. At the same time we can see increasing popularity of the so-called energy communities (e.g. cooperatives) which (i) enable groups of entities to invest in manage and benefit from shared RES energy infrastructure; (ii) are expected to increase the energy independence of local communities from large energy corporations and increase the share of RES. Analyses were conducted on 2000 randomly selected energy cooperatives and four energy cooperatives formed on the basis of actual data. The hypotheses assumed in the research and positively verified in this paper are as follows: (i) there is a relationship between hydrogen storage capacity and the power of RES which allows an energy community to build energy independence; (ii) the type of RES generating source is meaningful when optimizing hydrogen storage capacity. The paper proves it is possible to build “island energy independence” at the local level using hydrogen storage and the efficiency of the power-to-power chain. The results presented are based on simulations carried out using a dedicated optimization model implemented by mixed integer programming. The authors’ next research projects will focus on optimizing capital expenditures and operating costs using the Levelized Cost of Electricity and Levelized Cost of Hydrogen methodologies.