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Abstract

This paper presents the influence of cooling water regulation on power plant net efficiency. It was examined whether, for the non-nominal low-pressure turbine load, it is justified to reduce the cooling water pump load, and how it would affect the unit net efficiency. Calculations for two types of power units were carried out: with condensing and extractioncondensing turbine. The tested condensing power plant consists of three surface condensers. The calculation included four condensers’ connections set up on the cooling water side to check how the cooling water system pressure drop affects the net unit performance. The result has confirmed that implementing serial connection decreases net efficiency when cooling water flow regulation is used, but the mixed connection should be applied when pump load is not controlled. It was proved that the cooling water flow control gives a profit for both units. Net efficiency for combined heat and power plant can be improved by 0.1–0.5 pp, the gain is remarkable below 60% of the low-pressure turbine part load. Flow control implementation in the unit with condensing turbine water control gives a similar profit just below 80% of the turbine load. Next, an influence of the additional limitations of a cooling water system (minimal total pump head, cooling tower) affecting the feasibility of implementing the water control has been considered. Applying a multi-cell forced draft cooling tower does not have a significant impact on results, but when a natural draft cooling tower is used, the flow control range is strongly reduced.
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Bibliography

[1] Chmielniak T., Łukowicz H.: Modeling and optimization of coal power units with CO2 capture. WPS, Gliwice 2015 (in Polish).
[2] Chmielniak T., Łukowicz H.: Condensing power plant cycle assessing possibilities of improving its e?ciency. Arch. Thermodyn. 31(2010), 3, 105–113.
[3] Grzesiczek E., Mendecki J., Komarnicki Z.: Optimization of cooling water flow in 225 MW turbine condenser. Energetyka (2007), 8, 574–575.
[4] Rusak J.: Reduction of auxiliary energy consumption in TAURON Wytwarzanie S.A. on the example of cooling water systems modernization. Energetyka (2013), 1, 43–47.
[5] Laskowski R.: Wybrane zagadnienia modelowania i optymalizacji skraplaczy energetycznych i wymienników regeneracyjnych. Warszawa: Oficyna Wydawnicza Politechniki Warszawskiej, 2018.
[6] Laskowski R., Smyk A., Rusowicz A., Grzebielec A.: Optimization of the cooling water mass flow rate under variable load of a power unit. Appl. Therm. Eng. 191(2021), 116874.
[7] Gardzilewicz A., Błaszczyk A., Głuch J.: Operating and economic conditions of cooling water control for marine steam turbine condensers. Pol. Marit. Res. 18(2011), 3(70), 48–54.
[8] Harish R., Subhramanyan E.E., Madhavan R., Vidyanand S.: Theoretical model for evaluation of variable frequency drive for cooling water pumps in sea water based once through condenser cooling water systems. Appl. Therm. Eng. 30(2010), 2051–2057.
[9] Xia L., Liu D., Zhou L., Wang P., Chen Y.: Optimization of a seawater oncethrough cooling system with variable speed pumps in fossil fuel power plants. Int. J. Therm. Sci., 91(2015), 105–112.
[10] Dobkiewicz-Wieczorek E.: Cooling water mass flow optimization for low load of condensing turbine including CHP turbine. Rynek Energii (2020), 6, 15–20.
[11] Dobkiewicz-Wieczorek E.: Influence of surface condensers connection configuration on power plant unit performance. Arch. Thermodyn. 41(2020), 4, 115–145.
[12] Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of Water and Steam, The International Association for the Properties of Water and Steam. Lucerne 1997.
[13] Dobkiewicz-Wieczorek E.: Method for calculating the exhaust steam pressure of a condensing turbine. Energetyka (2019), 11, 725–730.
[14] KSB, Tips for the correct design of pumping stations equipped with submersible pumps. https://www.ksb.com/blob/173022/c7fe2d9f8e342c707efa5e0966136752/pumpenstation-download-data.pdf (accessed 6 Oct. 2021). [15] PN-76/M-34034 Pipelines – Principles of pressure loss calculations.
[16] EMBER, Average monthly wholesale electricity prices. https://ember-climate.org/european-electricity-transition/ (accessed 6 Oct. 2021).
[17] Market electrical energy price. https://wysokienapiecie.pl/40547-o-ile-wzrosna-cenypradu-w-2022-policzylismy/ (accessed 6 Oct. 2021).
[18] PSE, Daily market electrical energy price. https://www.pse.pl/dane-systemowe/funkcjonowanie-rb/raporty-dobowe-z-funkcjonowania-rb/podstawowe-wskazniki -cenowe-i-kosztowe/rynkowa-cena-energii-elektrycznej-rce (accessed 6 Oct. 2021).
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Authors and Affiliations

Ewa Dobkiewicz-Wieczorek
1

  1. Silesian University of Technology Department of Power Engineering and Turbomachinery, Konarskiego 18, 44-100, Gliwice, Poland
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Abstract

Hamburg with the quantity of about 18 mlns m2 is, alongside with Berlin and Munich, the biggest office centre in Germany. The large-scale planning and urban operations with the aim of location this function in the centre have been carried out since the beginning of the '60s. The policy of deployment the ofiice sites has beez modified since then, from isolating the monofunctional area of the Modernism's spirit, to multifunctional structures interplaying with the other sites when it comes to activities' potentiality with the expansion of the large-scale urban structures. Many recent realisations abound with significant buildings that bring the avant-garde approach to the idea of an office building. The high level of building technology and the importance of ecological aspects are the important distinction. The mentioned realizations has been noticed by the architectural critics and mentioned in professional press. The pride of place belongs to the works of BRT (Bothe-Richter-Teherani), that has created many innovatory office buildings.

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Authors and Affiliations

Maciej Złowodzki
Katarzyna Zawada-Pęgiel

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