Case study of two domestic hot water storage concepts in residential heat pump systems

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26110%2F26%3A0201667" target="_blank" >RIV/00216305:26110/26:0201667 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.3390/buildings16051034" target="_blank" >https://doi.org/10.3390/buildings16051034</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/buildings16051034" target="_blank" >10.3390/buildings16051034</a>

Result language

angličtina

Original language name

Case study of two domestic hot water storage concepts in residential heat pump systems

Original language description

This case study presents a comparative analysis of real-world operation two residential domestic hot water (DHW) preparation methods both connected to their own air-to-water heat pump (HP) located in Central Europe. One system employs a conventional configuration with separate tanks and an internal heating coil (HP-B), while the other features a compact tank-in-tank setup where DHW is heated via an integrated buffer tank (HP-A). Both systems were monitored under real operational conditions, with seasonal and annual coefficients of performance (COP, SCOP) calculated to evaluate efficiency. In the absence of complete thermal output data for one system, a reconstruction method based on the other’s performance and known heat losses was applied. The findings confirm that DHW system design significantly affects seasonal efficiency, particularly during summer operation when heating DHW dominates the energy load. The energy cost savings on heating during summer months could reach 44 %. The tank-in-tank system showed higher electrical consumption and lower SCOP due to internal heat transfer dynamics and dual-function operation. The study further shows associated energy and cost differences and demonstrates a practical approach to comparing real-world systems offering insights for design optimization and operational strategy. The authors of the article used the results of their research and experience from implementations as very effective feedback for further research and development. The novelty and uniqueness of the article lie in the energy comparison of two different connections of the hot water and heating water storage tanks with heat source systems using an “air-to-water” heat pump. The benefit of the solution in question is evident from the technical and economic evaluation.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

20101 - Civil engineering

Project

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Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2026

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Buildings

ISSN

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e-ISSN

2075-5309

Volume of the periodical

16

Issue of the periodical within the volume

5

Country of publishing house

CH - SWITZERLAND

Number of pages

28

Pages from-to

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UT code for WoS article

001713708000001

EID of the result in the Scopus database

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