Abstract:
Objective Long-term operation of ground source heat pump (Ground Source Heat Pump, GSHP) in hot areas will cause soil heat accumulation, while combined cooling, heating, and power (Combined Cooling Heating and Power, CCHP) is limited by the "cold fixed power" operation mode, resulting in limited system adjustment capacity and high operating costs. Therefore, an optimal scheduling method of regional integrated energy system (Regional Integrated Energy System, RIES) based on CCHP cold storage operation is proposed.
Method Firstly, the soil heat accumulation caused by the uneven operation time of GSHP in winter and summer was analyzed. Secondly, taking into account the optimization of CCHP power supply capacity in summer, by using CCHP for soil cold storage during the peak period of electricity price, the gas turbine power supply capacity was improved while part of GSHP heat removal was neutralized, so as to ensure the balance of soil heat removal in winter and summer. Finally, considering the constraints of energy balance and CCHP cold storage operation, a two-level optimal scheduling model was established with the goal of minimizing the system operating cost, and the simulation solution was carried out in the optimization software CPLEX.
Result The calculation results show that CCHP cold storage operation can improve the power supply capacity of gas turbine in summer and reduce the operating cost of the system. At the same time, the cold storage capacity can neutralize part of GSHP heat removal, so as to achieve the balance of soil heat removal throughout the year.
Conclusion The proposed method has good economic and environmental benefits, and effectively solves the problem of soil heat accumulation caused by long-term operation of GSHP in summer.