Water to water heat pump for district heating: modeling for MILP optimization and application to a real case study

Description

Water sourced heat pumps have the potential to play a large role in decarbonizing urban heat supply, for example in ultra-low temperature district heating systems when high temperature heat sources are not available. Understanding the effects of size and operation of heat pumps on the general performance of an energy system is not straightforward. Existing methods based on thermodynamic models are only applicable in a small range of circumstances, while models that assume constant COP fail to capture temperature dynamics. With this work, we present a generic linear model for water source heat pumps. We developed this model by fitting 251 data points from manufacturer data sheets of water-to-water and brine-to-water heat pumps in the 100 kWth to 1600 kWth range. The model is able to consider dynamic efficiency and temperature dependent linearization and is applicable for use in mixed-integer linear programming (MILP). For this, we use the energy hub modelling tool originally built by Gabrielli et al. (2017). Using the model, we have optimized the design and operation of a heating system for a residential neighborhood with 850 apartments and a shopping center in the Netherlands. We compared the optimal size and operation schedule of heat pumps as a stand-alone solution with several district heating configurations and grid temperature levels.

Period	2 Oct 2020 → 8 Oct 2020
Event title	International conference on smart energy systems: 4th generation district heating, electrification, electrofuels and energy efficiency
Event type	Conference
Conference number	6
Location	Aalborg, DenmarkShow on map
Degree of Recognition	International