Energy Measurement And Analysis Of Hospital Buildings In Changsha City

As people's living level improving, patients and workers are requiring a more and more comfortable indoor environment and energy consumption of hospital buildings is increasing greatly. Among 13 kinds of large public buildings in Changsha, Annual Energy Use Intensity (AEUI) of hospital buildings is just lower than marketplaces. Moreover, most hospital buildings can not meet the qualification set by Design Standard for Energy Saving of Public Buildings and thermal insulation has not been taken into account on the exterior walls.The basic architectural characteristics, energy consumption feature and the constitution of energy consumption of hospital buildings in Changsha are analyzed in this paper on the basic of energy consumption investigation and energy audit. Through comparing with energy of inhomogeneous public buildings and congener buildings of other city, the energy consumption of hospital buildings is analyzed and evaluated according to investigation data.Investigation results show that energy consumption of hospital buildings rises year by year and it is highest in 2007. The average AEUI is 195.04kWh/ (m2·a) and keeps on increasing, the energy consumption level is high. There is obvious difference among the AEUI of hospital buildings and the energy saving potential is great. Though energy consumption per square meter of building with electrothermal heating is lower than building without electrothermal heating, energy consumption expense per square meter of building with electrothermal heating is more than building without electrothermal heating. It shows that electrothermal heating is uneconomic. The consumption of natural gas of building without electrothermal heating is 65% of total energy consumption. It illustrates that energy consumption for heating is the main component of total energy consumption. The energy saving potential of heating in winter is great.Through analyzing and comparing energy consumption of buildings which function is different of certain typical hospital in Changsha, it shows that AEUI of outpatient and emergency department is the smallest, AEUI of inpatient building , care center and thoracic center is larger, and is 1.61, 2.12 and 2.07 times of outpatient and emergency department respectively. Energy consumption of medical equipment of outpatient and emergency department is relatively high and is just lower than air conditioning energy consumption, and it is lighting energy consumption in the other buildings. There are many problems in these buildings, such as the bad thermal performance of buildings structure, less using of energy saving lights, small temperature difference of in and out water of cooling water and chilled water, low automatization of monitoring and management and so on.Energy consumption of outpatient and emergency department of this hospital is simulated. The error of simulation results and investigation data is less than 11%. Energy saving effect of reconstruction of enclosure structure is simulated and analyzed. The reconstruction measures are adding 20 mm polystyrene composite plate on exterior walls, adding 30 mm polyurethane composite plate on roof and adopting Low-E coated insulating glass windows as external windows and it can save approximate 29.5% of air conditioning energy consumption.