Studies On Energy Consumption Of VAV System

The energy crisis of the seventies led to wildly development of variable air volume (VAV) system as a prefered method of air conditioning in America , Europe and other developed countries. It was unsuccessful for application of VAV system because of the lake of technique knowledge and economy in China and VAV system cannot be entirely accepted until now.This paper introduces the components of VAV system and seriets terminal units lhat are important for VAV system and are widely used So the paper presents to study energy consumption of VAV system with series terminal units of office building in ChinaBuildings are simulated through DeST that is software. Description of the buildings, characteristics of air conditioning system and indoor and outdoor environmental conditions etc are inputted. Annual dynamic loads of all the rooms and room basis temperature are gained through DeST. So energy consumption of fen, pump , cooling plane can be calculatedFor detailed analysis of energy savings of VAV system and considering that VAV system often is used to office buildings, three different office buildings including small, middle, large building are selected as simulates models. In the paper energy consumption of three types of air conditioning system, VAV system. Fan coil system and CAV for three different buildings is calculated A survey of energy use has been done and provides a basis for characterizing energy efficient The same study also explores the potential for energy savings in different climate, shenyang, shanghai, Xi'an. So simulating small building and compare energy consumption of VAV system with an equivalent Fan coil and CAV system for different climate.to the paper an analysis of the energy consumption of VAV and Fan coil and CAV for the three building models is presented. An energy savings of 6.3% and 11% is expected for small building model and middle building model comparing to Fan coil system For large building, an energy savings is amount to 23%. Compared to CAV the savings range above 35%. Total energy consumption of VAV system for different climate is less than Fan coil system and CAV system. Energy savings in Shenyang is a bit more than other two cities.By results the paper presents economic analysis of VAV system and calculates pay back time of VAV system. For small and middle buildings, pay back time is more ten ten years. For large building it is within five years. So investors can accept itVAV system that is a type of air conditioning system of energy-efficiency and intellectual has good future in China. It is good choice for new large buildings and existing buildings. Meanwhile the result can be used as directions to designers and investors.