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    The integration of a new waste-to-energy plant: Waste flows modelling and pricing strategies for financial sustainability
    (Elsevier, 2025-05-06) Němcová, Lucie; Pluskal, Jaroslav; Šomplák, Radovan
    The imperative to transform waste management and reduce reliance on landfills stands at the forefront of the EU’s ambitious objectives. While achieving complete material utilization of all waste is technically unattainable, the integration of Waste-to-Energy facilities into existing infrastructures emerges as a viable and environmentally conscious alternative. However, the economic sustainability of such facilities in developed countries is contingent upon navigating market dynamics. Evaluating the financial viability of a project often requires access to information that is highly confidential within the competitive environment. This article presents a novel modelling tool designed to estimate key parameters crucial for economic assessments of the construction of a new facility, using a limited set of publicly available data. The main feature of the approach is the modelling of the current collection areas within the existing network and the identification of the potential waste suitable for redirection to a new facility. Based on this information, a comprehensive pricing model has been developed, serving as a foundational framework for negotiations with individual waste producers and collection companies, contributing to the overall economic balance sheet. The approach is presented as a step-by-step guide with recommendations with partial examples from the case study in the Czech Republic. The paper highlights the significance of strategic partnership in economic sustainability and provides valuable insights for investing in waste management under real-world conditions. By securing stable input streams and long-term contracts, the volatility of revenue can be reduced and can also support establishment of a more environmentally and socially responsible system.
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    Model Development and Implementation of Techno-Economic Assessment of Hydrogen Logistics Value Chain: A Case Study of Selected Regions in the Czech Republic
    (MDPI, 2025-03-31) Poul, David; JIA, Xuexiu; Pavlas, Martin; Stehlík, Petr
    With the rising demand for renewable hydrogen as an alternative sustainable fuel, efficient transport strategies have become essential, particularly for regional and small-scale applications. While most previous studies focus on the long-distance transport of hydrogen, little attention has been given to the application in regions that are remote from major transmission infrastructure. This study evaluates the techno-economic performance of hydrogen road transport using multiple-element hydrogen gas containers and compares it with multimodal transport using rail. The comparison is performed for the southeastern region of the Czech Republic. The comprehensive techno-economic assessment incorporates detailed technical evaluations, precise fuel and energy consumption calculations, and realworld infrastructure planning to enhance accuracy. Results showed that multimodal transport of hydrogen can significantly reduce the cost for distances exceeding 90 km. The cost is calculated based on annual vehicle utilization, assuming the remaining utilization will be allocated to other tasks throughout the year. However, the cost-effectiveness of rail transportation is influenced by track capacity limits and possible delays. Additionally, this study highlights the crucial role of regional logistics hubs in optimizing transport modes, further reducing costs and improving efficiency.
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    Dynamic Reduction of Network Flow Optimization Problem: Case of Waste-to-Energy Infrastructure Planning in Czech Republic
    (Elsevier, 2024-10-01) Pluskal, Jaroslav; Šomplák, Radovan; Kůdela, Jakub; Eryganov, Ivan
    Nowadays, many sophisticated tools based on various mathematical approaches are used to support planning and strategic decision-making. In the field of waste management, allocation and location problems based mainly on the structure network flow problem are used with respect to infrastructure planning. Modern formulations of the problem allow the inclusion of integer and nonlinear constraints that reflect real-world operations. However, despite the advanced computational technology, such real-world problems are difficult to solve in adequate detail due to the large scale of the problem. Thus, the links in the system are simplified, but most often a transport network is aggregated. The individual nodes in the system may then represent areas with tens or hundreds of thousands of inhabitants, which does not provide sufficient insight for location tasks. This paper presents an approach to dynamically reduce the network with respect to selected points of interest. The selected areas are modeled in greater detail, while with increasing distance the entities are more aggregated into larger units. The approach is based on a transformation of the original network and subsequent cluster analysis, preferably using existing transport infrastructure. The presented approach provides the possibility of practical application of complex tools that are currently mostly theoretical due to high computational demands. The methodology is applied to a case study of Waste-to-Energy infrastructure planning, which needs to model a large area to fill a large capacity facility.
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    Experimentally Verified Flow Distribution Model for a Composite Modelling System
    (MDPI, 2021-03-23) Babička Fialová, Dominika; Jegla, Zdeněk
    A composite modelling system is currently being developed for accurate design of such complex heat transfer equipment. The modeling approach requires a flow distribution model enabling to yield accurate-enough predictions in reasonable time frames. The paper presents the results of complex experimental and modeling investigation of fluid flow distribution in dividing headers of tubular-type equipment. Different modeling approaches were examined on a set of header geometries. Predictions obtained via analytical and numerical models were validated using data from the experiments conducted on additively manufactured header samples. Two case studies employing parallel flow systems (mini-scale systems and a conventional-size heat exchanger) demonstrated the applicability of the distribution model and the accuracy of the composite modelling system.
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    Transient Thermal Stress Calculation of a Shell and Tube Condenser with Fixed Tubesheet
    (Wiley-VCH, 2021-10-12) Pernica, Marek; Létal, Tomáš; Lošák, Pavel; Naď, Martin; Reppich, Marcus; Jegla, Zdeněk
    The present article deals with transient thermal stress calculation on a safety horizontal shell and tube condenser. This condenser is used in a power plant for cooling of hot steam diverted from the turbine in the case of its emergency shutdown. The standard stress calculation was provided according to the EN 13445 standard in steady regime. As consistent with this calculation, an expansion joint must be used on the shell. The main aim of this article is to describe a detailed calculation of the transient temperature field on the shell and tubes, using finite element method analysis, and longitudinal thermal stresses on the shell and tubes during the start-up process. Transient analyses are useable for more accurate EN 13445 calculation and, furthermore, for fatigue calculation.