Analyses of seasonal thermal energy storage for a pumping & recharging well

Abstract:

Using the mathematical model validated by a field test,the perennial operation of pumping & recharging well(PRW) was simulated to explore the feasibility and potential of seasonal thermal energy storage(STES) of PRW.Meanwhile,a quantitative analysis model of STES was established based on the pumping and reinjection temperature.Results show that for the existence of thermal breakthrough,the operation of previous seasons has much effect on the temperature of pumping water in the later operation seasons.This behavior verifies that the PRW apparently has the phenomenon of STES.If the accumulated loads of space heating and cooling are kept in balance,the pumping temperature and the thermal energy storage ratio will basically remain unchanged.For a PRW in Beijing with summer-winter operation mode,the STES approximately provides 73% of low-temperature heat source and 24% of heat sink.However,if the accumulated loads are in unbalance,the pumping temperature will increase or reduce much annually and even the PRW may not work.