Air Conditioning Energy Consumption Measurment And Energy-saving Analysis Of A Library In Guangzhou

The large public building energy-saving is attracting more and more attention as the development of energy-saving work in our country. Library area more than20,000square meters as the large public buildings, energy consumption is the residential buildings5to15times, and the energy consumption of air conditioning system is the largest component of the total energy consumption of the building. Generally about40%to50%of building energy is consumed by air conditioning system. However, at present, in view of the library air conditioning energy consumption, there is lack of monitoring, diagnosis and analysis methods of system, and it is not clear enough to understand all aspects of energy consumption, these factors become an outstanding problem that affects energy-saving of air conditioning system. Therefore, the library air conditioning system running status measurement contribute to the diagnosis and analysis of all aspects of energy consumption, it has a great guiding significance to reduce the energy consumption of the library.A university library in Guangzhou is a large public building of such high energy consumption buildings. By its annual energy consumption data, it is known that library unit area of air conditioning costs are2.5times that of administration building, six times that of the classroom building in the same university. Cold consumption in unit air conditioning area of the library is135.5kW/(m2·a), in a high level, what’s more, energy consumption in unit air conditioning area is163.28kWh/m2, significantly higher than the public buildings in the same region. By in-depth analysis, it is known that the main reason of high energy consumption of air conditioning system has two aspects:First, The energy consumption of air conditioning system equipment operating improperly, result in air conditioning system with low energy efficiency; second, the full glass curtain wall outside the structure that takes up too high energy consumption of the air conditioning system, result in the air conditioning cooling consumption level of the building is too high;According to investigation, it is known that the library air quality unacceptable rate reach33.33%.The high-energy air conditioning system still exists air quality is difficult to meet the use requirements. By the measurement calculation, water transport factor of chilled water is29.08, energy efficiency ratio of terminal system is5.87, annual average energy consumption index of the major energy consuming equipment in air conditioning system are slightly lower specification limit values. Therefore, focused at the energy efficiency ratio of terminal system and water transport factor of condensate water to scheme further measurement program, Field testing and analysis building air conditioning system energy consumption equipment energy situation.The measuring result illustrates that, the temperature is too high supplied from the refrigerator station and the plate heat exchanger is less effective, result in the supply water temperature of chilled water is too high and the temperature difference between supply and return water is too small, and thus the dehumidification air conditioning ability at the end of processor gets low,which eventually led to energy efficiency ratio of air conditioning system low and unacceptable rate of the library air quality high.For air conditioning system problems, used the DeST-c energy consumption simulation software to establish building model, adopte the method combined local measurement with theoretical model to present reasonable energy-saving measures. Through a comprehensive analysis, propose the measures that install chillers to provide building cooling source alternative for area cold source, and Energy-saving effect of the program was simulated and economic analyzed. Results:After transformation, the energy consumption index of the library can meet the requirement of the air conditioning system of economic operation, the operation effect of air conditioning system has greatly improved. After transforming library years to save1.2108million yuan and the investment capital can be recovered in just1.94.Focus at the two reasons for the high school library air conditioning energy consumption, aparted from the active point of view to achieve energy-saving air conditioning system, also from the passive point of view to reduce the cooling load of the building air conditioning system in order to achieve the purpose of energy saving. Measurment and simulation analysis "shows that the main reason for the high unit area of the library cooling consumption indicators is that a large area of glass curtain wall structure, therefore proposed a professional film on the glass walls for energy saving measures. Simulation analysis on a variety of film, obtained that after fliming with complex IQue28H of glass flim, cooling consumption indicators unit area of the library is117.4kW/(m2·a) the investment capital can be recovered in4.4, can be used as energy-saving programs of the glass curtain wall. At the same time, simulated skylights and each side of the glass curtain wall film combination to analyze the best economic program. Obtained a short payback period of six months that the film of skylights, south and west than the film of the whole building, and invested to reduce by about400,000.