Abstract:

To determine the techno-economic of seasonal cold storage technology applied to protected agriculture, a group of solar greenhouses in Jinan was selected as the research object. To achieve year-round cold and heat management of the group of solar greenhouses, a seasonal cold storage system based on an ice source heat pump was used. The cold storage loss model and the energy savings, economic, and environmental benefit evaluation models were developed. The system's cold storage capacity, primary energy ratio (PER), annual cost, dynamic investment payback period, and pollutant emission reduction were then analyzed and compared to other heat pump and boiler systems. The results showed that: The annual cold capacity loss of the seasonal cold storage tank was less than 5%, the maximum cold storage capacity was 170409.07 GJ, 14509.47 GJ was remaining at the end of the year, and the group solar greenhouses' annual cooling and heating demand was met. The PER of seasonal cold storage system for cooling was 6.27 and the annual PER was 1.71, which meant that the application of seasonal cold storage technology greatly improves the energy efficiency and the energy-saving effect of the system. The system's operating costs were extremely low, the annual costs were low, and the dynamic investment payback period was 3.9～6.9 years, indicating that this system had good economic feasibility. When compared to an air source heat pump, this system could reduce 13897.90 tons t of CO₂, 3.61 tons of SO₂, 7.16 tons of NO_x, and 1.41 tons of smoke and dust per year with an emission reduction rate of 77.3%, indicating that the use of seasonal cold storage technology significantly reduced greenhouse gas and pollutant emissions and has significant environmental benefits.

Key words: seasonal cold storage, ice source heat pump, protected agriculture, techno-economic analysis