Estimation of annual energy loss by indoor air mixing

Excess energy consumption of HVAC system is not usually noticed without the dissatisfaction to thermal environment. Recently it has become easier to discover it in buildings with the aid of Building Energy Management System (BEMS). Indoor Air Mixing loss occurs in an office when the perimeter zone is heated by one HVAC system and the interior zone is cooled by the other system. The aim of this study is the quantitative analysis of the mixing energy loss in office buildings. Experiments are conducted in a full-size experiment room. The result shows that it is difficult to halt the mixing loss once the loss arises. After the reproduction of the simulation is confirmed by the comparison of results between experiment and simulation, several cases of simulation are conducted to quantify the annual energy loss in a model building. The comparison of results shows that preventing the mixing loss may reduce 9.4 % of the energy consumption of the whole building.