[{"doi":"10.1016/j.enconman.2026.121714","article_number":"121714","main_file_link":[{"open_access":"1","url":"https://www.sciencedirect.com/science/article/pii/S0196890426006837"}],"language":[{"iso":"eng"}],"publication_status":"published","date_updated":"2026-06-03T06:44:31Z","article_type":"original","intvolume":"       364","title":"Flexible operation strategies for heat pumps in district heating systems using dynamic electricity prices","year":"2026","publication_identifier":{"issn":["0196-8904"]},"author":[{"id":"56955","orcid":"0009-0006-8106-2132","last_name":"Rahlf","first_name":"Henning Christoph","full_name":"Rahlf, Henning Christoph"},{"full_name":"Divkovic, Denis","last_name":"Divkovic","first_name":"Denis","id":"89059"},{"full_name":"Knorr, Lukas","first_name":"Lukas","orcid":"0009-0005-4727-7511","last_name":"Knorr","id":"90391"},{"full_name":"Schlosser, Florian","first_name":"Florian","last_name":"Schlosser","id":"88614"},{"full_name":"Meschede, Henning","first_name":"Henning","last_name":"Meschede","orcid":"0000-0002-1538-089X","id":"86954"}],"type":"journal_article","keyword":["Heat transition","Optimisation","Temperature flexibility","Decarbonisation","Multi energy"],"department":[{"_id":"644"},{"_id":"534"}],"date_created":"2026-06-03T06:34:27Z","abstract":[{"text":"Electrifying the heating sector is essential for achieving global climate targets like the Paris Agreement’s 1.5 °C goal. In Germany, where 80  % of household energy goes to space heating and hot water, shifting to low-carbon solutions is crucial. Fossil-fuelled district heating networks can incorporate renewable energy via heat pumps, improving efficiency. Although heat pump design typically favours minimal temperature lifts, higher lifts can be economically viable with low electricity prices and abundant renewables. Adding thermal energy storage boosts operational flexibility. This study explores a flexible heat pump operation incorporating part load behaviour with a thermal energy storage in a German city’s district heating system to minimise costs and carbon dioxide emissions. Using a mixed-integer linear programming model, it examines the impact of temperature adjustments and storage on system efficiency. The results show that the integration of a heat pump in a district heating system reduces operating costs. Compared to a supply without a heat pump, with levelised cost of heating of 9.98 cent/kWhth and a fixed operating mode with costs between 9.96 cent/kWhth and 11.49 cent/kWhth, the flexible use results in lowest costs of 9.85 cent/kWhth, while also reducing overall CO2 emissions. Using a full factorial sensitivity analysis, the levelised cost of heating ranged between 9.15 cent/kWhth in the best case and 10.37 cent/kWhth in the worst case for the selected configuration.","lang":"eng"}],"publication":"Energy Conversion and Management","user_id":"56955","volume":364,"_id":"65757","publisher":"Elsevier BV","status":"public","oa":"1","project":[{"_id":"1495","name":"FlexLabQuartier"}],"citation":{"bibtex":"@article{Rahlf_Divkovic_Knorr_Schlosser_Meschede_2026, title={Flexible operation strategies for heat pumps in district heating systems using dynamic electricity prices}, volume={364}, DOI={<a href=\"https://doi.org/10.1016/j.enconman.2026.121714\">10.1016/j.enconman.2026.121714</a>}, number={121714}, journal={Energy Conversion and Management}, publisher={Elsevier BV}, author={Rahlf, Henning Christoph and Divkovic, Denis and Knorr, Lukas and Schlosser, Florian and Meschede, Henning}, year={2026} }","ama":"Rahlf HC, Divkovic D, Knorr L, Schlosser F, Meschede H. Flexible operation strategies for heat pumps in district heating systems using dynamic electricity prices. <i>Energy Conversion and Management</i>. 2026;364. doi:<a href=\"https://doi.org/10.1016/j.enconman.2026.121714\">10.1016/j.enconman.2026.121714</a>","mla":"Rahlf, Henning Christoph, et al. “Flexible Operation Strategies for Heat Pumps in District Heating Systems Using Dynamic Electricity Prices.” <i>Energy Conversion and Management</i>, vol. 364, 121714, Elsevier BV, 2026, doi:<a href=\"https://doi.org/10.1016/j.enconman.2026.121714\">10.1016/j.enconman.2026.121714</a>.","short":"H.C. Rahlf, D. Divkovic, L. Knorr, F. Schlosser, H. Meschede, Energy Conversion and Management 364 (2026).","chicago":"Rahlf, Henning Christoph, Denis Divkovic, Lukas Knorr, Florian Schlosser, and Henning Meschede. “Flexible Operation Strategies for Heat Pumps in District Heating Systems Using Dynamic Electricity Prices.” <i>Energy Conversion and Management</i> 364 (2026). <a href=\"https://doi.org/10.1016/j.enconman.2026.121714\">https://doi.org/10.1016/j.enconman.2026.121714</a>.","ieee":"H. C. Rahlf, D. Divkovic, L. Knorr, F. Schlosser, and H. Meschede, “Flexible operation strategies for heat pumps in district heating systems using dynamic electricity prices,” <i>Energy Conversion and Management</i>, vol. 364, Art. no. 121714, 2026, doi: <a href=\"https://doi.org/10.1016/j.enconman.2026.121714\">10.1016/j.enconman.2026.121714</a>.","apa":"Rahlf, H. C., Divkovic, D., Knorr, L., Schlosser, F., &#38; Meschede, H. (2026). Flexible operation strategies for heat pumps in district heating systems using dynamic electricity prices. <i>Energy Conversion and Management</i>, <i>364</i>, Article 121714. <a href=\"https://doi.org/10.1016/j.enconman.2026.121714\">https://doi.org/10.1016/j.enconman.2026.121714</a>"}},{"date_created":"2021-12-20T08:23:13Z","department":[{"_id":"187"}],"keyword":["Economic ExperimentM","Investment Decisions","Tax Effects","Timing Flexibility","Uncertainty"],"type":"journal_article","publication":"FinanzArchiv / European Journal of Public Finance","issue":"1-2","abstract":[{"text":"This study investigates the conditions under which tax rate changes accelerate risky investments.\r\nWhile tax rate increases are often expected to harm investment, analytical\r\nstudies find tax rate increases may foster investment under flexibility.We design a theorybased\r\nexperimentwith a binomial random walk and entry–exit flexibility.We find accelerated\r\ninvestment upon tax rate increases irrespective of an exit option, but no corresponding\r\nresponse to tax cuts. This asymmetry may be due to tax salience and mechanisms\r\nfrom irreversible choice under uncertainty. Given this evidence of unexpected tax-reform\r\neffects, tax policymakers should carefully consider behavioral aspects.","lang":"eng"}],"language":[{"iso":"eng"}],"author":[{"last_name":"Fahr","first_name":"René","full_name":"Fahr, René"},{"full_name":"Janssen, Elmar A.","first_name":"Elmar A.","last_name":"Janssen"},{"id":"530","full_name":"Sureth-Sloane, Caren","first_name":"Caren","orcid":" 0000-0002-8183-5901","last_name":"Sureth-Sloane"}],"year":"2022","title":"Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment","article_type":"original","intvolume":"        78","publication_status":"published","date_updated":"2026-04-09T07:25:41Z","citation":{"short":"R. Fahr, E.A. Janssen, C. Sureth-Sloane, FinanzArchiv / European Journal of Public Finance 78 (2022) 239–289.","ama":"Fahr R, Janssen EA, Sureth-Sloane C. Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment. <i>FinanzArchiv / European Journal of Public Finance</i>. 2022;78(1-2):239-289.","chicago":"Fahr, René, Elmar A. Janssen, and Caren Sureth-Sloane. “Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment.” <i>FinanzArchiv / European Journal of Public Finance</i> 78, no. 1–2 (2022): 239–89.","bibtex":"@article{Fahr_Janssen_Sureth-Sloane_2022, title={Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment}, volume={78}, number={1–2}, journal={FinanzArchiv / European Journal of Public Finance}, author={Fahr, René and Janssen, Elmar A. and Sureth-Sloane, Caren}, year={2022}, pages={239–289} }","mla":"Fahr, René, et al. “Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment.” <i>FinanzArchiv / European Journal of Public Finance</i>, vol. 78, no. 1–2, 2022, pp. 239–89.","apa":"Fahr, R., Janssen, E. A., &#38; Sureth-Sloane, C. (2022). Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment. <i>FinanzArchiv / European Journal of Public Finance</i>, <i>78</i>(1–2), 239–289.","ieee":"R. Fahr, E. A. Janssen, and C. Sureth-Sloane, “Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment,” <i>FinanzArchiv / European Journal of Public Finance</i>, vol. 78, no. 1–2, pp. 239–289, 2022."},"quality_controlled":"1","_id":"29049","page":"239-289","volume":78,"user_id":"96670","jel":["H25","H21","C91"],"status":"public"},{"type":"conference","keyword":["Keywords: Load-Shifting","Demand-Side-Management","DSM","grid frequency","EEX","electricity trading prices","renewable share","flexibility","emissions","CO2"],"department":[{"_id":"53"}],"file":[{"date_created":"2022-01-06T12:35:49Z","creator":"krauter","file_id":"29172","success":1,"content_type":"application/pdf","relation":"main_file","date_updated":"2022-01-06T12:35:49Z","file_name":"Krauter Zhang - Triggering DSM - EUPVSEC 2020.pdf","file_size":1309449,"access_level":"closed"}],"date_created":"2020-09-14T12:43:43Z","abstract":[{"text":"To provide a simple instrument to operate residential Load-Shifting or Demand-Side-Management \r\nsystems, the measurement of the actual grid frequency seems to be an appropriate method. Due to the present \r\ninflexibility and the lack of sufficient throttling capabilities of lignite and nuclear power plants, a surplus of \r\nelectricity generation occurs during periods of high wind and solar power generation. While the specific CO2-\r\nemission is decreasing then ‒ due to the increased share of Renewables, the grid frequency is increasing (to a certain \r\nlimit). Using the grid frequency as an indicator to switch-on and off certain loads (loads that do not require power \r\npermanently (e.g. dishwashers, washing machines, dryers, fridges and freezers, heaters) could provide a simple, \r\ninexpensive demand-side management indicator to lower specific CO2‒emssions and costs (if a dynamic \r\nconsumption tariff is available). To check the truthfulness of that hypothesis, the grid and frequency data of the \r\nGerman grid of the year 2018 have been collected and a the correlation between grid frequency, power surplus, share \r\nof renewables vs. CO2-contents and price at the European energy exchange (EEX) have been calculated. The results \r\nshow: Correlation between frequency and share of renewables is quite low (r = 0.155) due to the fact that primary \r\ngrid control quickly compensates deviations from the 50 Hz nominal frequency. There is a good anti-correlation (r = -\r\n0.687) between the EEX‒prices and the share of renewables in the grid. Over the years, correlation between \r\nelectricity trading prices (EEX) and CO2 emissions is quite good (r =0.665), within the one year (2018) that \r\ncorrelation almost doesn’t exist, possibly due to the inflexibility of the bulky lignite power plants that even operate at \r\nnegative prices. \r\n","lang":"eng"}],"publication":"Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.","doi":"10.4229/EUPVSEC20202020-6BV.5.9","language":[{"iso":"eng"}],"date_updated":"2022-01-06T12:42:22Z","publication_status":"published","year":"2020","title":"Triggering Demand‒Side‒Management: Correlation of electricity prices, share of renewables, CO2‒contents, and grid‒frequency in the German electricity grid.","publication_identifier":{"issn":["\t3-936338-73-6"]},"author":[{"full_name":"Krauter, Stefan","first_name":"Stefan","orcid":"0000-0002-3594-260X","last_name":"Krauter","id":"28836"},{"full_name":"Zhang, L.","last_name":"Zhang","first_name":"L."}],"quality_controlled":"1","file_date_updated":"2022-01-06T12:35:49Z","citation":{"chicago":"Krauter, Stefan, and L. Zhang. “Triggering Demand‒Side‒Management: Correlation of Electricity Prices, Share of Renewables, CO2‒contents, and Grid‒frequency in the German Electricity Grid.” In <i>Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.</i>, 1815–17, 2020. <a href=\"https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9\">https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9</a>.","short":"S. Krauter, L. Zhang, in: Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020., 2020, pp. 1815–1817.","apa":"Krauter, S., &#38; Zhang, L. (2020). Triggering Demand‒Side‒Management: Correlation of electricity prices, share of renewables, CO2‒contents, and grid‒frequency in the German electricity grid. <i>Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.</i>, 1815–1817. <a href=\"https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9\">https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9</a>","ieee":"S. Krauter and L. Zhang, “Triggering Demand‒Side‒Management: Correlation of electricity prices, share of renewables, CO2‒contents, and grid‒frequency in the German electricity grid.,” in <i>Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.</i>, online, 2020, pp. 1815–1817, doi: <a href=\"https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9\">10.4229/EUPVSEC20202020-6BV.5.9</a>.","ama":"Krauter S, Zhang L. Triggering Demand‒Side‒Management: Correlation of electricity prices, share of renewables, CO2‒contents, and grid‒frequency in the German electricity grid. In: <i>Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.</i> ; 2020:1815-1817. doi:<a href=\"https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9\">10.4229/EUPVSEC20202020-6BV.5.9</a>","bibtex":"@inproceedings{Krauter_Zhang_2020, title={Triggering Demand‒Side‒Management: Correlation of electricity prices, share of renewables, CO2‒contents, and grid‒frequency in the German electricity grid.}, DOI={<a href=\"https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9\">10.4229/EUPVSEC20202020-6BV.5.9</a>}, booktitle={Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.}, author={Krauter, Stefan and Zhang, L.}, year={2020}, pages={1815–1817} }","mla":"Krauter, Stefan, and L. Zhang. “Triggering Demand‒Side‒Management: Correlation of Electricity Prices, Share of Renewables, CO2‒contents, and Grid‒frequency in the German Electricity Grid.” <i>Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.</i>, 2020, pp. 1815–17, doi:<a href=\"https://doi.org/10.4229/EUPVSEC20202020-6BV.5.9\">10.4229/EUPVSEC20202020-6BV.5.9</a>."},"ddc":["620"],"user_id":"28836","page":"1815 - 1817","_id":"19393","has_accepted_license":"1","status":"public","conference":{"location":"online","name":"37th European Photovoltaic Solar Energy Conference and Exhibition (EUPVSEC 2020)","start_date":"2020-09-07","end_date":"2020-09-11"}}]