In issue 12/2025

Słowa kluczowe: industrial waste heat recovery, energy efficiency of industrial sectors, heat recovery technologies, industrial decarbonization, waste heat temperature, closed loop economy (GOZ)

Streszczenie:
Waste heat recovery (OCO) is a key element in improving energy efficiency and achieving decarbonization goals in European Union (EU) industrial sectors. The paper analyzes OCO technologies for three characteristic temperature ranges of the waste heat stream, i.e.: low-temperature sources (t <120°C), średniotemperaturowych (t =120°C-400°C) oraz wysokotemperaturowych (t > 400°C). These ranges were used to evaluate the suitability of recovery technologies such as heat exchangers, heat pumps, organic Rankine cycle (ORC) systems, regenerative systems and other solutions used in industrial practice. The methodology included classification of waste heat streams, selection of technologies for specific temperature ranges, and evaluation of their application in specific sectors. The results of the 2D and 3D visualizations indicate that the greatest heat recovery potential is for energy-intensive sectors, while low- and medium-temperature sectors require more specialized technologies. The study underscores that OCO is one of the most cost-effective and environmentally efficient measures to support a closed-loop economy and improve the energy efficiency of EU industry, thus fitting in with the EU's climate goals.

Słowa kluczowe: Photovoltaic (PV, )power system, Ground Source Heat and Mass Exchanger

Streszczenie:
Introduction: The article deals with the subject of increasing the operating efficiency of photovoltaic (PV) panels through their cooling - an important issue in the context of the growing importance of these devices for the national power system, especially in the climatic zone of Poland during the summer. The high operating temperature of the cells (especially during the summer peak) leads to a reduction in their power and efficiency. Aim: To evaluate the possibility of using a Ground-Based Heat and Mass Exchanger (BGWCiM) to cool and improve the performance of photovoltaic panels. Methods: The study was based on the analysis of the energy balance and efficiency of an example photovoltaic panel operating under typical meteorological conditions of the warm period of Wroclaw in an hourly progression, carried out by computational methods. Conclusions and reference to practical applications: The proposed Analyzed solution makes it possible to reduce temperature losses, which directly leads to an increase in efficiency and instantaneous power of the panel and higher efficiency of the inverter operation. Active cooling can also slow down their degradation (including PID and LET processes) caused by long-term overheating, thereby extending the life of the panels. In addition, the system provides an opportunity to use the heat for snow removal and de-icing of module surfaces during the winter.

Słowa kluczowe: building energy performance indicators, final energy, net delivered energy, non-renewable primary energy

Streszczenie:
An amendment to the Ordinance on the Methodology for Determining the Energy Performance of a Building or Part of a Building and Energy Performance Certificates is planned for June 30, 2026. The draft of the new version of this regulation envisages a number of changes, including regarding the energy performance indicators of buildings. In particular, it proposes to revise the definition of the final energy demand of a building, introduces the concept of net delivered energy demand and a new indicator of annual net delivered energy demand. It also provides for the calculation of the demand for non-renewable primary energy using an energy balance performed on the net delivered energy frontier, rather than on the basis of the final energy demand as before. The presented article discusses and illustrates, with examples, the differences in the rules for calculating energy performance indicators between the current regulation on this issue and the draft of its new version.

Słowa kluczowe: modeling, pollutant concentrations, PM10, intersection

Streszczenie:
Around the world, modern cities are facing a growing problem of air pollution, which is one of the most serious threats to public health, the environment and quality of life. Pollution comes from many sources - primarily road transportation, industry and heating systems. In densely built-up urban areas, where air flow is limited and emissions are concentrated, it becomes particularly important to understand the mechanisms of spreading these substances. That is why the authors focused on modeling the concentrations of pollutants from linear emissions in urban space. This article presents the results of numerical studies of the dispersion of air pollutants from linear (traffic) sources, i.e. road transport (particulate pollutants) using real data from field surveys carried out with mobile measuring devices (using a selected road intersection as an example). As a result of the numerical analysis, the influence of traffic routes and accompanying traffic on the state of air quality was found, which was confirmed in actual measurement data. In addition, the probable influx of pollutants from surrounding buildings was noted, and the fact that pollutants move in accordance with the direction of the wind was confirmed.

Słowa kluczowe: water recovery, condensate, air handling unit, fan coil unit

Streszczenie:
In the face of increasing demands for energy efficiency and sustainability, increasing attention is being paid to opportunities for the recovery and reuse of water resources in buildings. One potential but still underestimated source of water is condensate generated in ventilation and air conditioning systems - both in air conditioning units and air handling units. This paper presents an analysis of the potential for condensate recovery and utilization in a large office facility. It discusses the mechanisms of condensate formation in cooling and heat recovery processes, ways of collecting and draining condensate, and the potential for its use. The ventilation and air conditioning system in an existing office building located in Warsaw was analyzed. Based on the results of the calculations, the volume of recoverable water condensing on radiators in air handling units and fan coil units was estimated at more than 70,000 liters per year. The period for which the reclaimed water would be sufficient to cover the building's needs for flushing toilet bowls and watering green areas was approximated.

Słowa kluczowe: rainwater, stormwater drainage, authoritative rain intensity

Streszczenie:
The article presents an analysis of the rainwater drainage system in an existing warehouse facility with an office and social area. The starting material for the analysis was the documentation provided by the facility administrator. The scope of the analysis also included the identification of potential design and execution errors and corrective tools to improve the functionality of the rainwater drainage system. Methods, used in the design of rainwater drainage systems, for determining authoritative rainfall intensities were analyzed.

Słowa kluczowe: ventilation, phase change materials, PCM, heat recovery, polish climate

Streszczenie:
Introduction: The use of PCM phase-change materials for heat recovery in mechanical ventilation is becoming increasingly popular. This is influenced by the need to strive for energy-saving solutions, as well as climate change affecting the increasing use of air-conditioning systems. Purpose: The purpose of this paper is to analyze the feasibility of using PCM phase-change materials in heat exchangers in decentralized ventilation, particularly in the climate of Poland, and to evaluate the possibility of using PCM in cooling and heating functions, including how to select PCM for local conditions. Methods: A review of 16 scientific publications on the use of PCMs in ventilation was performed, an analysis of PCM parameters (melting point, stability, safety of use, toxicity) was carried out, and temperature ranges were identified that allow PCMs to regenerate during the day-night cycle in summer and winter. Conclusions and reference to practical applications: The use of PCM phase-change materials can improve the energy efficiency of decentralized ventilation, which is important for retrofitted buildings. It was shown that the optimal melting temperature of PCMs for summer (cooling mode) is 16°C-20°C and for winter (heating mode) is 7°C-16°C, and the selection of PCMs must be based on local weather data (preferably hourly). It was evaluated that it is possible to select a single PCM for both modes, but this requires a design compromise.