THERMAL SCIENCE

International Scientific Journal

Qi Zhao

,

Bo Tian

,

Bowen Chu

,

Yingcheng Wang

,

Fayv Wu

,

Haotian Hu

RESEARCH ON APPLICABILITY AND OPTIMIZATION OF SOLAR-DUAL-SOURCE HEAT PUMP HYBRID HEATING SYSTEMS IN SEVERELY COLD REGIONS

ABSTRACT
This study proposes a solar-dual-source (ground source + air source) heat pump hybrid heating system. Targeting the heating needs of severely cold regions, a typical office building in Harbin was used as the model. Hourly simulation models of three systems-independent ground source heat pump, solar-ground source heat pump, and solar-dual-source heat pump-were constructed using TRNSYS software. The system prioritizes solar energy for cross-seasonal heat storage, with an air source heat pump as an auxiliary system and a ground source heat pump as a backup. A quality-adjusted variable water supply temperature strategy is employed. Ten-year simulations show that the soil temperature decreased by 6.88℃ with the independent ground source heat pump system, by 1.25℃ with the solar-ground source heat pump system, and by a slight increase of 0.25℃ with the solar-dual-source heat pump system. The Hybrid Genetic Particle Swarm Optimization Algorithm was used to perform multi-objective optimization of nine parameters, including collector area, hot water storage tank volume, air source heat pump capacity, buried pipe depth, and key control temperature difference. After optimization, the COP of both ground-source and air-source heat pumps improved, the collector outlet temperature increased by approximately 33%, and overall energy efficiency was significantly improved. In a comprehensive assessment of energy, economic, and environmental benefits, the system demonstrated clear advantages, providing a reliable solution for low-carbon heating in frigid regions.
KEYWORDS
Soil thermal balance, TRNSYS, Hybrid Genetic Particle Swarm Optimization Algorithm, Low-carbon heating, Solar-dual source heat pump
PAPER SUBMITTED: 2026-01-01
PAPER REVISED: 2026-05-13
PAPER ACCEPTED: 2026-06-09
PUBLISHED ONLINE: 2026-07-11
DOI REFERENCE: https://doi.org/10.2298/TSCI260101095Z
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Research on applicability and optimization of solar-dual-source heat pump hybrid heating systems in severely cold regions

© 2026 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International licence