Repository logo

Infoscience

  • English
  • French
Log In
Logo EPFL, École polytechnique fédérale de Lausanne

Infoscience

  • English
  • French
Log In
  1. Home
  2. Academic and Research Output
  3. Journal articles
  4. Optimization of hybrid sensible-latent seasonal heat storage systems
 
research article

Optimization of hybrid sensible-latent seasonal heat storage systems

Delgado-Díaz, William  
•
Villasmil, Willy
•
Troxler, Marcel
Show more
December 1, 2025
Applied Energy

This study presents a coupled techno-economic and environmental model of hybrid sensible-latent thermal energy storage (TES) systems, integrating phase change material (PCM) macro-capsules to enhance storage capacity and performance. The multi-scale model accounts for stratification in the sensible storage and phase change dynamics in the PCM capsules. This framework is used to perform multi-objective optimization across the full range of thermal self-sufficiency (SSth) levels for a multi-family building. The results show that a 70 % SSth offers the optimal balance between economic feasibility and environmental impact, with a Levelized Cost of Heat (LCOH) of 0.27 CHF/kWh and a Global Warming Potential (GWP) reduction of 76 % compared to fossil fuel alternatives. Systems targeting up to 85 % SSth are technically feasible but come with increased costs (up to 0.33 CHF/kWh), while exceeding 85 % SSth results in exponential increases in both cost and storage volume. Maximizing photovoltaic (PV) and heat pump (HP) power is critical for optimizing system performance. Future advancements in PCM technology and decreasing PV costs could lower the LCOH to 0.23 CHF/kWh and the GWP to 21 % of fossil fuel systems, demonstrating significant potential for long-term cost reductions and sustainability.

  • Files
  • Details
  • Metrics
Type
research article
DOI
10.1016/j.apenergy.2025.126235
Scopus ID

2-s2.0-105011396995

Author(s)
Delgado-Díaz, William  

École Polytechnique Fédérale de Lausanne

Villasmil, Willy

Hochschule Luzern

Troxler, Marcel

Hochschule Luzern

Hijwegen, Ruben

Hochschule Luzern

Hendry, Reto

Hochschule Luzern

Schilt, Ueli

Hochschule Luzern

Roos, Philipp

Cowa Thermal Solutions AG

Ravotti, Rebecca

Hochschule Luzern

Stamatiou, Anastasia

Hochschule Luzern

Haussener, Sophia  

École Polytechnique Fédérale de Lausanne

Show more
Date Issued

2025-12-01

Published in
Applied Energy
Volume

399

Article Number

126235

Subjects

Global warming potential (GWP)

•

Hybrid sensible-latent thermal energy storage

•

Levelized cost of heat (LCOH)

•

Phase change materials (PCM)

•

Seasonal thermal energy storage (STES)

Editorial or Peer reviewed

REVIEWED

Written at

EPFL

EPFL units
LRESE  
FunderFunding(s)Grant NumberGrant URL

Planergie AG

Cowa Thermal Solutions AG

Swiss Federal Office of Energy

SI/502171,SI/502259

Available on Infoscience
August 20, 2025
Use this identifier to reference this record
https://infoscience.epfl.ch/handle/20.500.14299/252955
Logo EPFL, École polytechnique fédérale de Lausanne
  • Contact
  • infoscience@epfl.ch

  • Follow us on Facebook
  • Follow us on Instagram
  • Follow us on LinkedIn
  • Follow us on X
  • Follow us on Youtube
AccessibilityLegal noticePrivacy policyCookie settingsEnd User AgreementGet helpFeedback

Infoscience is a service managed and provided by the Library and IT Services of EPFL. © EPFL, tous droits réservés