In the quest for sustainable energy solutions, a groundbreaking study led by Lu Ding, published in the Journal of Refrigeration, has introduced a novel combined cooling and heating system that could revolutionize how we manage energy in distributed areas. This innovative system, based on an absorption heat pump, harnesses a variety of clean and renewable energies, including solar heat, geothermal, waste heat, biomass, and air-source energy, to provide efficient cooling and heating over an impressive temperature range from -20 ℃ to 90 ℃.
The system, designed to be suitable for villages, cities, and industrial parks, addresses a critical need in the context of carbon neutrality. By leveraging multiple energy sources, it ensures a stable and reliable energy supply, even in areas far from centralized cooling and heating networks. “The key innovation here is the ability to integrate various renewable energy sources seamlessly,” Ding explains. “This not only enhances the system’s efficiency but also significantly reduces its carbon footprint.”
The prototype, developed as part of this research, utilizes a vacuum tube collector to capture solar thermal energy and incorporates natural gas as a supplementary heat source to balance fluctuations in solar energy. This dual-energy approach ensures an all-weather stable energy supply, making the system robust and reliable. The prototype, tested in Jinan, demonstrated a solar thermal ratio of 35%, showcasing the system’s potential for widespread adoption.
One of the standout features of this system is its ability to drive multiple sets of indoor heating and cooling terminals through medium circulation and valve switching using a single set of absorption heat pumps and outdoor units. This design not only simplifies the system’s architecture but also enhances its operational efficiency. “The system’s flexibility and efficiency make it a game-changer for distributed energy management,” Ding notes.
The environmental benefits are equally impressive. The study found that by introducing solar thermal energy and ambient energy recovery, the fraction of renewable energy in the system exceeded 50%. Compared to traditional methods like gas furnaces plus air conditioning, the proposed system reduced annual operating costs by over 54.3% and carbon emissions by 44%. These figures underscore the significant commercial and environmental impacts of this technology.
The coefficient of performance (COP) of the system is also noteworthy. For cooling, the COP ranged from 0.30-0.43 at -20 ℃ and 0.70-0.78 at 7 ℃, with cooling water temperatures varying from 30 ℃ to 20 ℃. For heating, the COP reached 1.40-1.90 at 45 ℃ and 1.35-1.56 at 80 ℃, with evaporation temperatures varying from -15 ℃ to 20 ℃. These performance metrics highlight the system’s versatility and efficiency across different temperature ranges.
The implications of this research are far-reaching. As the energy sector continues to evolve towards more sustainable practices, systems like the one proposed by Ding could become the norm. The ability to integrate multiple renewable energy sources and achieve significant cost and emission reductions makes this technology a compelling option for both residential and industrial applications. The study, published in Zhileng xuebao, or the Journal of Refrigeration, marks a significant step forward in the field of energy management and sustainability.
