@article{65757,
  abstract     = {{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.}},
  author       = {{Rahlf, Henning Christoph and Divkovic, Denis and Knorr, Lukas and Schlosser, Florian and Meschede, Henning}},
  issn         = {{0196-8904}},
  journal      = {{Energy Conversion and Management}},
  keywords     = {{Heat transition, Optimisation, Temperature flexibility, Decarbonisation, Multi energy}},
  publisher    = {{Elsevier BV}},
  title        = {{{Flexible operation strategies for heat pumps in district heating systems using dynamic electricity prices}}},
  doi          = {{10.1016/j.enconman.2026.121714}},
  volume       = {{364}},
  year         = {{2026}},
}

@article{29049,
  abstract     = {{This study investigates the conditions under which tax rate changes accelerate risky investments.
While tax rate increases are often expected to harm investment, analytical
studies find tax rate increases may foster investment under flexibility.We design a theorybased
experimentwith a binomial random walk and entry–exit flexibility.We find accelerated
investment upon tax rate increases irrespective of an exit option, but no corresponding
response to tax cuts. This asymmetry may be due to tax salience and mechanisms
from irreversible choice under uncertainty. Given this evidence of unexpected tax-reform
effects, tax policymakers should carefully consider behavioral aspects.}},
  author       = {{Fahr, René and Janssen, Elmar A. and Sureth-Sloane, Caren}},
  journal      = {{FinanzArchiv / European Journal of Public Finance}},
  keywords     = {{Economic ExperimentM, Investment Decisions, Tax Effects, Timing Flexibility, Uncertainty}},
  number       = {{1-2}},
  pages        = {{239--289}},
  title        = {{{Can Tax Rate Changes Accelerate Investment under Entry and Exit Flexibility? – Insights from an Economic Experiment}}},
  volume       = {{78}},
  year         = {{2022}},
}

@inproceedings{19393,
  abstract     = {{To provide a simple instrument to operate residential Load-Shifting or Demand-Side-Management 
systems, the measurement of the actual grid frequency seems to be an appropriate method. Due to the present 
inflexibility and the lack of sufficient throttling capabilities of lignite and nuclear power plants, a surplus of 
electricity generation occurs during periods of high wind and solar power generation. While the specific CO2-
emission is decreasing then ‒ due to the increased share of Renewables, the grid frequency is increasing (to a certain 
limit). Using the grid frequency as an indicator to switch-on and off certain loads (loads that do not require power 
permanently (e.g. dishwashers, washing machines, dryers, fridges and freezers, heaters) could provide a simple, 
inexpensive demand-side management indicator to lower specific CO2‒emssions and costs (if a dynamic 
consumption tariff is available). To check the truthfulness of that hypothesis, the grid and frequency data of the 
German grid of the year 2018 have been collected and a the correlation between grid frequency, power surplus, share 
of renewables vs. CO2-contents and price at the European energy exchange (EEX) have been calculated. The results 
show: Correlation between frequency and share of renewables is quite low (r = 0.155) due to the fact that primary 
grid control quickly compensates deviations from the 50 Hz nominal frequency. There is a good anti-correlation (r = -
0.687) between the EEX‒prices and the share of renewables in the grid. Over the years, correlation between 
electricity trading prices (EEX) and CO2 emissions is quite good (r =0.665), within the one year (2018) that 
correlation almost doesn’t exist, possibly due to the inflexibility of the bulky lignite power plants that even operate at 
negative prices. 
}},
  author       = {{Krauter, Stefan and Zhang, L.}},
  booktitle    = {{Proceedings of the 37th European Photovoltaic Solar Energy Conference, 07 - 11 September 2020.}},
  issn         = {{	3-936338-73-6}},
  keywords     = {{Keywords: Load-Shifting, Demand-Side-Management, DSM, grid frequency, EEX, electricity trading prices, renewable share, flexibility, emissions, CO2}},
  location     = {{online}},
  pages        = {{1815 -- 1817}},
  title        = {{{Triggering Demand‒Side‒Management: Correlation of electricity prices, share of renewables, CO2‒contents, and grid‒frequency in the German electricity grid.}}},
  doi          = {{10.4229/EUPVSEC20202020-6BV.5.9}},
  year         = {{2020}},
}