Wyniki wyszukiwania - Biblioteka Nauki

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The impact of electrification of heating on the power grid for a selected area microgrids

100%

Laskowski M. , Krajewski K. , Chaja P. , Zawadzki P. , Bykuć S.

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2023

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tom Vol. 44, no 4

221--241

EN

In an era of changes in the electricity market, where the share of renewable energy sources is increasing and moving away from conventional coal-based energy, the electricity used for heating is gaining importance, for example to power heat pumps. They currently are one of the most common ways for heating buildings as an alternative to fossil fuels and biomass. In this article, the authors present an analysis aimed at answering the question whether using the concept of microgrids in Polish realities provides a feasible solution. Within the framework of this article, analyses were carried out by assuming the electrification of the heating installation of users in a local microgrid located in a selected location of the Polish low-voltage distribution network. The increase in electricity demand needed to generate the corresponding amount of heat was then estimated, and subsequently the impact of this demand on the microgrid was determined. In addition, in the article, the authors estimate the production of a prosumer PV installation at the selected location and analyze the level of autoconsumption of the generated electricity in the PV installation by the heat pump.

2

Testing of a price-based system for power balancing on real-life HVAC installation in real life

86%

Radziszewska W. , Bugaj M. A. , Łuniewski M. , Hoogsteen G. , Chaja P. , Bykuć S.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

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tom Vol. 70, nr 2

art. no. e140690

EN

HVAC systems use a substantial part of the whole energy usage of buildings. The optimizing of their operation can greatly affect the power use of a building, making them an interesting subject when trying to save energy. However, this should not affect the comfort of the people inside. Many approaches aim to optimize the operation of the heating and cooling system; in this paper, we present an approach to steer the heat pumps to reduce energy usage while aiming to maintain a certain level of comfort. For this purpose, we employ a market-based distributed method for power-balancing. To maintain the comfort level, the market-based distributed system assigns each device a cost-curve, parametrized with the current temperature of the room. This allows the cost to reflect the urgency of the HVAC operation. This approach was tested in a real-world environment: we use 10 heat pumps responsible for temperature control in 10 comparable-sized rooms. The test was performed for 3 months in summer. We limited the total peak power, and the algorithm balanced the consumption of the heat pumps with the available supply. The experiments showed that the system successfully managed to operate within the limit (lowering peak usage), and - to a certain point – reduce the cost without significantly deteriorating the working conditions of the occupants of the rooms. This test allowed us to estimate the minimal peak power requirement for the tested set-up that will still keep the room temperatures in or close to comfortable levels. The experiments show that a fully distributed market-based approach with parametrized cost functions can be used to limit peak usage while maintaining temperatures.

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Adsorption chiller in a combined heating and cooling system: simulation and optimization by neural networks

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Krzywanski J. , Sztekler K. , Bugaj M. , Kalawa W. , Grabowska K. , Chaja P. R. , Sosnowski M. , Nowak W. , Mika Ł. , Bykuć S.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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tom Vol. 69, nr 3

art. no. e137054

EN

Adsorption cooling and desalination technologies have recently received more attention. Adsorption chillers, using eco-friendly refrigerants, provide promising abilities for low-grade waste heat recovery and utilization, especially renewable and waste heat of the near ambient temperature. However, due to the low coefficient of performance (COP) and cooling capacity (CC) of the chillers, they have not been widely commercialized. Although operating in combined heating and cooling (HC) systems, adsorption chillers allow more efficient conversion and management of low-grade sources of thermal energy, their operation is still not sufficiently recognized, and the improvement of their performance is still a challenging task. The paper introduces an artificial intelligence (AI) approach for the optimization study of a two-bed adsorption chiller operating in an existing combined HC system, driven by low-temperature heat from cogeneration. Artificial neural networks are employed to develop a model that allows estimating the behavior of the chiller. Two crucial energy efficiency and performance indicators of the adsorption chiller, i.e., CC and the COP, are examined during the study for different operating sceneries and a wide range of operating conditions. Thus this work provides useful guidance for the operating conditions of the adsorption chiller integrated into the HC system. For the considered range of input parameters, the highest CC and COP are equal to 12.7 and 0.65 kW, respectively. The developed model, based on the neurocomputing approach, constitutes an easy-to-use and powerful optimization tool for the adsorption chiller operating in the complex HC system.

4

Development of wind farms in Poland in the context of climate change

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Hyrzyński R. , Jaroszewska M. , Badur J. , Ziółkowski P. , Gotzman S. , Froissart M. , Bykuć S. , Dudda W.

Rynek Energii

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2022

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tom Nr 3

82--94

EN

This paper summarises the ongoing transformation in the structure of Polish power system. This is a very complex process which fits into global megatrends in this matter. It needs to take into account such crucial elements like socially responsible investments, life cycle assessment, policy changes and investments strategies. United Nations climate policy urges to take certain actions to combat climate change and its impact. It highlights new record high levels of greenhouse gases content in the atmosphere. Presented graphs contain data extracted from the Polish power system showing intra-day, monthly and annual load distribution. Particular attention is paid to the variability of wind energy sources and their efficiency (full load equivalent operating hours factor). Discussed aspects does not address any issues related to the stability of the power system. Additionally, it does not contain any polemic with the cited research results. On their basis it can be pointed out that wind farms contribute to a local temperature and precipitation increase. The nature of this phenomenon (positive or negative) in the context of global warming is currently the subject of worldwide research. Nevertheless, it can be said with certainty that the environmental impact of renewable sources usage is significantly lower than in the case of classic power plants based on fossil fuels.

PL

W artykule przedstawiono zagadnienia związane z szeroko pojętym rozwojem energetyki wiatrowej. Jako tło nakreślono strukturę mocy i produkcji energii na świecie, przeanalizowano prognozy rozwoju energetyki na najbliższe lata (analiza megatrendów) i w tym kontekście dosyć szczegółowo omówiono zagadnienia związane z rozwojem energetyki wiatrowej. Na podstawie dostępnych badań przybliżono także zagadnienia związane z czynnikami wpływającymi na rozwój odnawialnych źródeł energii oraz ich oddziaływaniem na środowisko naturalne. W tym celu odniesiono się do wyników dwóch badań. Autorzy nie podejmują jednakże ich krytyki, czy nawet oceny, natomiast odniesienia do takowej krytyki, przeprowadzonej przez innych autorów, przywołano w treści. Praca nie podejmuje także zagadnień związanych z bezpieczeństwem i stabilnością pracy systemu elektroenergetycznego. Stwierdzono, że elektrownie wiatrowe przyczyniają się do lokalnego wzrostu temperatury w miejscu ich zainstalowania, a także do wzrostu opadów. Niezależnie od oceny wyników tychże badań z całą odpowiedzialnością można stwierdzić, że oddziaływanie odnawialnych źródeł energii jest znacząco mniejsze niż źródeł konwencjonalnych.