Case analysis of heat pump integration in district heating system
Abstract
The installation of heat pumps in district heating (DH) systems is one of the most promising technologies to increase the efficiency of heat supply by using renewable energy sources and reducing heat carrier temperatures in the networks. The possibilities of installing heat pumps in DH systems are very wide, but most often the main purpose of their application is to increase the temperature of the supplied heat carrier at the heat substations of individual consumers or their groups. This paper describes a study that analyzed the possibilities of integrating an individual heat pump at a heat substation in a building to reduce the temperature of the heat carrier in the return line. The results of the study revealed the dependences of the reduction of the heat demand of the building from the DH network, the power of the heat pump, the coefficient of performance (COP), and the reduction of the return temperature.
Article in Lithuanian.
Šilumos siurblio integravimo centralizuoto šilumos tiekimo sistemoje atvejo analizė
Santrauka
Šilumos siurblių diegimas centralizuoto šilumos tiekimo (CŠT) sistemose yra viena perspektyviausių technologijų, padedančių padidinti šilumos tiekimo efektyvumą, panaudojant atsinaujinančius energijos išteklius ir mažinant šilumnešio temperatūras tinkluose. Šilumos siurblių įrengimo CŠT sistemose galimybės yra labai plačios, tačiau dažniausiai pagrindinis jų taikymo tikslas susijęs su tiekiamo šilumnešio temperatūros didinimu atskirų vartotojų ar jų grupių šilumos punktuose. Šiame straipsnyje aprašomas tyrimas, kurio metu buvo analizuojamos individualaus šilumos siurblio integravimo pastato šilumos punkte galimybės, siekiant sumažinti šilumnešio temperatūrą grįžtamojoje linijoje. Tyrimo rezultatai atskleidė pastato šilumos poreikio sumažėjimo iš CŠT tinklo, šilumos siurblio galios, naudingo veikimo koeficiento (COP) ir grįžtamosios temperatūros sumažėjimo priklausomybes.
Reikšminiai žodžiai: centralizuotas šilumos tiekimas, šilumos siurbliai, žemų temperatūrų šilumos tiekimas, naudingo veikimo koeficientas (COP).
Keyword : district heating, heat pumps, low temperature heat supply, COP
This work is licensed under a Creative Commons Attribution 4.0 International License.
References
Frederiksen, S., & Werner, S. (2013). District heating and cooling. Studentlitteratur AB.
Li, H., Svendsen, S., Gudmundsson, O., Kuosa, M., Rämä, M., Sipilä, K., Blesl, M., Broydo, M., Stehle, M., Pesch, R., Pietruschka, D., Huther, H., Grajcar, M., Jentsch, A., Kallert, A., Schmidt, D., Nord, N., Tereshchenko, T., Park, P. B.-S., … Bevilacqua, C. (2017). Future low temperature district heating design guidebook: Final Report of IEA DHC Annex TS1. Low temperature district heating for future energy systems. Technical Univerity of Denmark.
Mendoza-Miranda, J. M., Mota-Babiloni, A., Ramírez-Minguela, J. J., Muñoz-Carpio, V. D., Carrera-Rodríguez, M., Navarro-Esbrí, J., & Salazar-Hernández, C. (2016). Comparative evaluation of R1234yf, R1234ze(E) and R450A as alternatives to R134a in a variable speed reciprocating compressor. Energy, 114, 753–766. https://doi.org/10.1016/j.energy.2016.08.050
Ommen, T., Markussen, W. B., & Elmegaard, B. (2014). Heat pumps in combined heat and power systems. Energy, 76, 989–1000. https://doi.org/10.1016/j.energy.2014.09.016
Ommen, T., Thorsen, J. E., Markussen, W. B., & Elmegaard, B. (2017). Performance of ultra low temperature district heating systems with utility plant and booster heat pumps. Energy, 137, 544–555. https://doi.org/10.1016/j.energy.2017.05.165
Østergaard, P. A., & Andersen, A. N. (2016). Booster heat pumps and central heat pumps in district heating. Applied Energy, 184, 1374–1388. https://doi.org/10.1016/j.apenergy.2016.02.144
Østergaard, P. A., & Andersen, A. N. (2018). Economic feasibility of booster heat pumps in heat pump-based district heating systems. Energy, 155, 921–929.
https://doi.org/10.1016/j.energy.2018.05.076
Popiel, C. O., & Wojtkowiak, J. (1998). Simple formulas for thermophysical properties of liquid water for heat transfer calculations (from 0°C to 150°C). Heat Transfer Engineering, 19(3), 87–101. https://doi.org/10.1080/01457639808939929
Sayegh, M. A., Jadwiszczak, P., Axcell, B. P., Niemierka, E., Bryś, K., & Jouhara, H. (2018). Heat pump placement, connection and operational modes in European district heating. Energy and Buildings, 166, 122–144.
https://doi.org/10.1016/j.enbuild.2018.02.006
Vivian, J., Emmi, G., Zarrella, A., Jobard, X., Pietruschka, D., & de Carli, M. (2018). Evaluating the cost of heat for end users in ultra low temperature district heating networks with booster heat pumps. Energy, 153, 788–800. https://doi.org/10.1016/j.energy.2018.04.081
Yang, X. (2016). Supply of domestic hot water at comfortable temperatures by low-temperature district heating without risk of legionella. Technical University of Denmark, Department of Civil Engineering.
Zajacs, A., Bogdanovics, R., & Borodinecs, A. (2020). Analysis of low temperature lift heat pump application in a district heating system for flue gas condenser efficiency improvement. Sustainable Cities and Society, 57, 102130.
https://doi.org/10.1016/j.scs.2020.102130
Zühlsdorf, B., Meesenburg, W., Ommen, T. S., Thorsen, J. E., Markussen, W. B., & Elmegaard, B. (2018). Improving the performance of booster heat pumps using zeotropic mixtures. Energy, 154, 390–402.
https://doi.org/10.1016/j.energy.2018.04.137
Zyczkowski, P., Borowski, M., Łuczak, R., Kuczera, Z., & Ptaszyński, B. (2020). Functional equations for calculating the properties of low-GWP R1234ze(E) refrigerant. Energies, 13(12), 3052. https://doi.org/10.3390/en13123052