BIM Enabled Life Cycle Environmental And Cost Analysis Of A Prototype Of Small Scale Zero Energy House

In order to actively respond to global warming,reduce carbon emissions and fossil fuel combustion,the international community has developed a number of "zero-energy building" and a similar definition to carry out technical research since the 1970 s.The theory and methodology of Life Cycle Assessment(LCA)and Life Cycle Cost(LCC)has provided a broader perspective and a more comprehensive way of thinking for building sustainability research.Building Information Modeling(BIM)can provide an inter-disciplinary data platform that could be shared among design,construction,operation,and demolition stages of a building project.Combining LCA with BIM,it is possible to evaluate and improve the various stages of the building life cycle more efficiently and comprehensively.Passive extra-low energy consumption buildings reduce their operation cost through passive design strategies,high-performing building envelopes,and efficient mechanical systems.Zero energy buildings further reduce non-renewable energy consumption by applying renewable energy systems such as PV modules.These two types of energy efficient buildings often have higher embodied energy,environmental impacts and costs in both building materials and equipments,and have higher requirements in maintenance and replacement of building parts.Thus,it is necessary to establish BIM model to analyze their environmental and economical performances across their entire life cycle through BIM-LCA tool comprehensively.This paper first present the research results of zero energy buildings and LCA,and clarifies the development status of LCA methodology based on BIM.Secondly,the concepts and definitions of zero energy building,zero carbon building and other energy efficient buildings are studied.Describe the importance of quantifying the environmental impact and cost of zero-energy buildings from the life cycle.Based on integrating BIM with LCA and LCC methods,the economic impacts and LCC values of a small scale residential building under three different energy-saving scenariosand two different energy systems are analyzed and compared.The three energy-saving scenarios are general energy-saving buildings,passive extra-low energy consumption buildings and zero energy buildings.The two different energy systems are composite energy system basing on radiant panels and ground source heat pump.The results show that zero energy consumption buildings and Plus Energy Buildings have obvious advantages in lowering their PE and GWP values,while passive extra-lowenergy consumption buildings have good environmental benefits.In terms of economic benefits,due to the low energy price of residential buildings and based on recent price index,the initial and replacement cost of zero and passive extra-low energy consumption buildings will offset the energy saving benefit during operation,which makes their life cycle costs higher than regular energy efficient buildings.However,if the increase rate of energy price grows higher than that of building material and construction price in future 50 years,zero energy buildings will have advantage in life cycle cost.In the heating and cooling system of renewable energy,the life cycle environmental impacts and LCC of the ground source heat pump system have advantages compared with the composite energy system basing on radiant panels in addition to the initial cost.