Multi-energy complementary heat pumps for low-carbon integrated cooling, heating, and water supply in districts: case study of a school campus

Abstract

Integrated multi-energy complementary approaches constitute effective low-carbon solutions for mitigating energy consumption and emissions within decentralized settings such as campuses and industrial facilities. This study investigates the integration and operational performance of a distributed multi-energy complementary system designed for near-zero carbon campus operation. The primary scientific objective is to evaluate the synergistic control and energy efficiency of a triple-hybrid (ground-source + solar + air-source) system under real-world conditions, with a focus on mitigating ground thermal imbalance. The system integrates ground-source heat pumps, solar thermal collectors, and air-source heat pumps to deliver space heating and cooling for 900 m² of classroom facilities while supplying domestic hot water for 750 residents. The innovative hierarchical control strategy prioritizes renewable sources and ensures stable operation under dynamic loads. Under demanding operating conditions, the system maintains a coefficient of performance (COP) exceeding 3.9. The study provides empirical long-term performance data, addressing a critical gap in the literature between simulation and real-world validation. Through synergistic integration of energy generation, storage, and intelligent control, the system achieves reliable cooling, heating, and hot water supply, establishing a replicable framework for low-carbon campuses.