---
_id: '66007'
abstract:
- lang: eng
  text: <jats:p>The reduction of CO2-emissions in the chemical industry is essential
    to meet European climate targets. Particularly, the reliance on fossil fuels for
    process heat supply is a key factor for CO2-emissions. Electrically driven compression
    heat pumps are a promising option to reduce fossil fuel consumption by upgrading
    low-temperature waste heat to a higher temperature level, provided that low-carbon
    electricity is available. However, the integration of heat pumps into chemical
    utility systems remains a challenge due to economic constraints and the high complexity
    associated with site-wide heat integration and retrofit of existing structures.
    This work presents a mixed-integer linear programming (MILP) approach for the
    optimization of utility systems with integrated heat pumps. To address computational
    complexity, candidate utility temperature levels are pre-selected, and feasible
    heat pump coefficients of performance (COP) are precomputed. The framework is
    applied to both greenfield and retrofit scenarios for a synthetic case study consisting
    of 400 process streams. In the greenfield scenario, optimal utility temperature
    levels and heat pump integration configurations are identified. For the retrofit
    scenario, temperature levels of an existing utility system are modified to reduce
    total annual costs (TAC). Additionally, sensitivity analysis is conducted to assess
    the influence of key economic and environmental parameters. The presented case
    studies demonstrate short solution times, highlighting the suitability of the
    proposed framework for screening studies and systematic sensitivity analyses in
    early-stage design and retrofit applications.</jats:p>
author:
- first_name: Thorben
  full_name: Hochhaus, Thorben
  last_name: Hochhaus
- first_name: Marcus
  full_name: Grünewald, Marcus
  last_name: Grünewald
- first_name: Julia
  full_name: Riese, Julia
  id: '101499'
  last_name: Riese
  orcid: 0000-0002-3053-0534
citation:
  ama: 'Hochhaus T, Grünewald M, Riese J. Optimization of Site-wide Heat-Integrated
    Utility Systems with Heat Pumps using MILP. In: <i>Systems and Control Transactions</i>.
    Vol 6. PSE Press; 2026. doi:<a href="https://doi.org/10.69997/sct.152209">10.69997/sct.152209</a>'
  apa: Hochhaus, T., Grünewald, M., &#38; Riese, J. (2026). Optimization of Site-wide
    Heat-Integrated Utility Systems with Heat Pumps using MILP. <i>Systems and Control
    Transactions</i>, <i>6</i>. <a href="https://doi.org/10.69997/sct.152209">https://doi.org/10.69997/sct.152209</a>
  bibtex: '@inproceedings{Hochhaus_Grünewald_Riese_2026, title={Optimization of Site-wide
    Heat-Integrated Utility Systems with Heat Pumps using MILP}, volume={6}, DOI={<a
    href="https://doi.org/10.69997/sct.152209">10.69997/sct.152209</a>}, booktitle={Systems
    and Control Transactions}, publisher={PSE Press}, author={Hochhaus, Thorben and
    Grünewald, Marcus and Riese, Julia}, year={2026} }'
  chicago: Hochhaus, Thorben, Marcus Grünewald, and Julia Riese. “Optimization of
    Site-Wide Heat-Integrated Utility Systems with Heat Pumps Using MILP.” In <i>Systems
    and Control Transactions</i>, Vol. 6. PSE Press, 2026. <a href="https://doi.org/10.69997/sct.152209">https://doi.org/10.69997/sct.152209</a>.
  ieee: 'T. Hochhaus, M. Grünewald, and J. Riese, “Optimization of Site-wide Heat-Integrated
    Utility Systems with Heat Pumps using MILP,” in <i>Systems and Control Transactions</i>,
    2026, vol. 6, doi: <a href="https://doi.org/10.69997/sct.152209">10.69997/sct.152209</a>.'
  mla: Hochhaus, Thorben, et al. “Optimization of Site-Wide Heat-Integrated Utility
    Systems with Heat Pumps Using MILP.” <i>Systems and Control Transactions</i>,
    vol. 6, PSE Press, 2026, doi:<a href="https://doi.org/10.69997/sct.152209">10.69997/sct.152209</a>.
  short: 'T. Hochhaus, M. Grünewald, J. Riese, in: Systems and Control Transactions,
    PSE Press, 2026.'
date_created: 2026-06-22T11:32:30Z
date_updated: 2026-06-22T11:33:05Z
department:
- _id: '831'
doi: 10.69997/sct.152209
intvolume: '         6'
language:
- iso: eng
publication: Systems and Control Transactions
publication_identifier:
  issn:
  - 2818-4734
publication_status: published
publisher: PSE Press
quality_controlled: '1'
status: public
title: Optimization of Site-wide Heat-Integrated Utility Systems with Heat Pumps using
  MILP
type: conference
user_id: '101499'
volume: 6
year: '2026'
...