The Analysis Of HVAC System With Air-to-Air Energy Recovery

Air-to-air energy recovery equipments and systems appeared with the demands of energy-saving of the HVAC system and the indoor air quality. Using air-to- air energy recovery equipments, we can efficiently recover the energy in the outlet air and use it to precool or preheat the outdoor air. So we can enlarge the proportion of the fresh air while saving the energy.This paper analyses the influence of the air-to-air energy recovery equipment to energy-saving of the HVAC system; analyses the life cycle cost of HVAC system with it; then analyses the influence of it to in door air quality.Used the curve of the temperature and enthalpy, analyzed the energy saving of the system, and got the formula of the energy-saving proportion. Took three typical cities in China as examples, calculated the energy-saving percent of HVAC system in each city with air-to-air energy recovery equipments (both HRV and ERV). They all got very good results. And also, we found three factors influenced the energy-saving: heat exchange efficiency, the operating time and the difference of temperature (or enthalpy) between indoor air and outdoor air.Introduced the method and steps of life cycle cost analyse of the HVAC system with air-to-air energy recovery equipment. Took a commercial building in Wuhan for example to analyze and got the conclusion that using this equipment it can save 8.4 yuan/year.m2, and the investment could be payback in 3.2 years.Using these equipments can also enlarge the proportion of the fresh air, improve the indoor air quality.As the improvement of people's consciousness,air-to-air energy recovery equipment would be used much more broadly, also would bring much more benefits to human-beings.