Gabi培训-Handout6.pdfVIP

More life cycle analysis (Short Cut) 2 Embodied Energy and CO 2 Footprint Embodied Energy = the energy required to create 1 kg of material. It includes all the energy required to make the material and that contained within the feed stock. CO 2 foot print = amount of CO 2 released into the atmosphere as a consequence of the manufacture of 1 kg of material. These two factors do not have to be proportional. Each of these quantities will have been determined by a lifecycle analysis. The life-cycle analysis should have taken into account the form of the energy used, and how it was produced (e.g. the local energy mix). Here we will make use of the Cambridge Engineering Selector (CES), which you can all access in the DPO. The material selector now contains eco-information on each material. 1 Further Reading: Chapter 16 of Materials Selection in Mechanical Design, by Prof. Ashby covers this material in detail 3Eco-Selector (CES) Available data includes: Embodied Energy, CO 2 foot print, NOx and SOx creation for the material, Information on disposal routes, processing energy for common operations Figure 1. Entry in the Material Selector for Poly-Propylene 4 Embodied Energy Embodied Energy = the energy required to create 1 kg of material. It includes all the energy required to make the material and that contained within the feed stock. The embodied energy is made up of two components: Embodied Energy = Intrinsic energy + energy used in production Energy input during productionThe heat of combustion of any Non-Renewable feed-stocks (e.g. oil) used to make the product. Some of this intrinsic energy may be recoverable by combustion 5Embodied energy and CO 2 footprint Wood (Typical) Embodied Energy = 2-3.8 MJ/kg CO 2 Footprint = -1.16 to -1.05 kg/kg Polyethylene Embodied Energy = 76.9-85 MJ/kg CO 2 Footprint = 1.95-2.16 kg/kg Figure 2. The embodied energy of various materials vs the CO 2 footprint. 6 The relative importance of each stage Figure 3