Study On Indoor Environment Status And Energy Consumption In Heating Residential Buildings In The Winter In Lanzhou

Energy Conservation has already become a theme now under the situation of Energy Crisis. Like other cities in China,the contradiction between building energy consumption and economic growth is very outstanding in Lanzhou.Lanzhou is in cold zone in China,summer is very cool here,air conditioning equipment is not used much,but winter is cold and long,so for residential buildings,the building energy consumption is focused on Winter Heating. Assessment on the building environment performance and energy consumption of existing residential building in Lanzhou supplied basic information for developing the Lanzhou sustainable development housing policy.The questionnaire investigation of residential buildings' general situation,heating modes, resident evaluations on indoor thermal environment,building energy consumption,building lighting environment and building acoustics environment are carried out in Lanzhou in Gansu Province.Actual measurements are also carried out on typical residential buildings on indoor temperature.The indoor temperature,outdoor temperature and their influencing factors are compared between different types of thermal insulation residential buildings.Then use building energy consumption software DeST-h to simulate the building energy consumption on each one of those three different thermal-insulation buildings.Compare the indoor temperature and energy consumption,analyze the energy saving effect.And at last,the renovation on non-thermal-insulation residential building is simulated and indoor temperature and building consumption before and after the renovation is compared.The investigation result shows that only 51%residents are satisfied of their indoor thermal environment.The subjective and objective assessments of indoor thermal comfort have a great difference between different types of thermal insulations in residential buildings,and 90%exterior-thermal-insulation residents are satisfied of their indoor thermal environment. The questionnaire investigation results of different thermal insulation residential buildings are compared,the results shows that the exterior-thermal-insulation technology has a excellent performance and it will do great help to create comfortable indoor thermal environment and energy saving in buildings.Most residents in Lanzhou support the development of sustainable building.For building renovation,most residents can't afford the renovation cost.The potential on energy saving is significant.The light environment is mostly satisfied.The sound pollution is little.And the overall subjective assessment is good.Choose 6 apartments to measure the indoor temperature,including 2 non-thermal-insulation residential buildings,1 interior-thermal-insulation residential building,and 3 exterior-thermal-insulation residential buildings.Major apparatus are Kanomax Climomaster with A531 probe,Swema Air300 with SWE03 probe,and one infrared temperature measurement equipment made in China.The outdoor temperature during measurement period is supported by Lanzhou area weather center.The measure shows that the indoor temperature of non-thermal-insulation residential buildings is affected a lot by environment factors,its amplitude is big,its value is small,and so the indoor thermal environment is poor.But the environment factors influence little to the indoor-thermal-insulation residential buildings,its major influencing factors are BTM(building thermal mass) and heating effect,the indoor temperature accords with the criterion value,its amplitude is small,and the indoor thermal environment is good.The indoor temperature of exterior-thermal-insulation residential buildings is major influenced by BTM and heating effect,but its value is too high,even 6℃higher than criterion value,it could cause energy waste.The indoor temperature,outdoor temperature and their influencing factors are compared between different types of thermal insulation residential buildings,it is strongly advised to use exterior-thermal-insulation technology to create comfortable indoor thermal environment and reduce building energy consumption.Choose each one of these three different types of thermal insulation residential buildings to take energy consumption simulation.Compare the results with actual measure and get those conclusions as follows.Non-thermal-insulation models use typical non-thermal-insulation exterior-wall.The trend of simulation temperature and actual temperature is similar,the error is acceptable.The simulation result shows that for this non-thermal-insulation residential building,its windows are in the right size and the value of cold load in summer and heat load in winter is in normal range.The interior-thermal-insulation model use typical interior-thermal-insulation exterior-wall.The trend of simulation temperature and actual temperature is also similar,and the error is even smaller.But the crest of the temperature doesn't appear at the same time,this maybe related to the different regulation methods between software and the fact.The heat load in winter is a little bigger than normal residential building because its window takes 50%area of the wall,but at the same time the cold load in summer is smaller.The exterior-thermal-insulation model use typical exterior-thermal-insulation exterior-wall.The compared result between simulation results and measurement is just the same as interior-thermal-insulation model.In the exterior-thermal-insulation model the window is a little small so the cold load in summer is a little bigger and the heat load in winter is a little smaller.The simulation value of indoor thermal environment was basically consistent with the actual value,and the error was acceptable,which shows that the residence indoor thermal environment could be forecasted with computer simulation.The interior and exterior renovation simulation was taken to typical non-thermal-insulation residential buildings.The compared results show that after the renovation the indoor-temperature is increased and the building energy consumption is decreased.So it's very necessary to take renovation to those old residential buildings which need it.