Energy efficiency of an air conditioning system coupled with a pipe-embedded wall and mechanical ventilation

Recently, impressive progress has been made in the utilization of natural sources for free cooling. However, few studies have investigated the effects of the combination of a pipe-embedded envelope with ventilation. In this study, the dynamic simulation platform TRNSYS were used to calculated the free-running temperature and cooling load of a typical office room in four typical cooling climate regions. The rooms were equipped with mechanical ventilation and/or pipe-embedded cooling systems. The pipe-embedded cooling system refers to the pipe-embedded envelope integrated with ground source heat exchangers (GSHX). The energy consumptions of the air conditioning system and the free cooling system in different coupling systems were calculated. The results show that pipe-embedded cooling systems have great potential for decreasing energy consumption. The non-air conditioning ratio is increased significantly by utilizing pipe-embedded cooling systems for free cooling, and the energy savings ratio is over 80% in Beijing. Mechanical ventilation is quite effective in mild climate regions, and the energy savings ratio in Kunming is approximately 48%. The combination of the mechanical ventilation system and the pipe-embedded cooling system can further lead to an increase in an additional 13% of the energy savings ratio in hot summer and warm winter climate regions.