Development of a Disaggregated Hybrid Model for Life Cycle Assessment and De-manufacturing

The de-manufacturing stage is an overlooked component of most current LCA （life cycle assessment） methodologies. Most of the current LCA techniques do not fully account for the usage of the product and end of life aspects. This paper introduces a comprehensive methodology that takes strong consideration of the inventory costs of use and end of life of the functional unit by combining manufacturing and de-manufacturing into the centerpiece of the hybrid analysis. In order to obtain this goal, a new disaggregated model was developed by enhancing current LCA hybrid methods related to life cycle inventory compilations. The new methodology is also compared to existing methodologies.

National water use of coal-fired power generation:Hybrid life cycle assessment in China

Previous studies of water use for coal-fired power generation may have overlooked inter-sectoral impacts in the supply chain.Indeed,to devise effective water conservation strategies during the ongoing energy transition,it is of utmost importance to analyze the sectoral water use structures and flows in the supply chain and identify the sources of water scarcity.Therefore,based on the power sector-split environmentally extended input-output(EEIO)model and the life cycle assessment(LCA)idea,we comprehensively analyze the nexus between coal-fired power generation and water use from a sectoral perspective.Our findings reveal a complex and diverse water use structure in coal-fired power generation.The technology of production inherently determines the high intensity of water withdrawal,and the close intersectoral linkages,particularly with agriculture,construction,and some industrial sectors,in the production process result in an intricate web of indirect water withdrawal and blue water footprint(WF).Moreover,the grey WF,primarily sourced from coal mining and indirectly tied to tertiary industries,underscores critical areas for attention in water pollution management.Finally,water use in the coal-fired power sector is projected to remain at elevated levels in the short to medium term under various transition strategies.Following an in-depth exploration of the coal-fired power-water use nexus,the findings can offer new perspectives and specific entry points for sustainable energy development and water resource management.

Cost of non-renewable energy in production of wood pellets in China

Assessing the extent to which all bio-fuels that are claimed to be renewable are in fact renewable is essential because producing such renewable fuels itself requires some amount of non-renewable energy （NE） and materials. Using hybrid life cycle analysis （LCA）--from raw material collection to delivery of pellets to end users--the energy cost of wood pellet production in China was estimated at 1.35 J/J, of which only 0.09 J was derived from NE, indicating that only 0.09 J of NE is required to deliver 1 J of renewable energy into society and showing that the process is truly renewable. Most of the NE was consumed during the conversion process （46.21%） and delivery of pellets to end users （40.69%）, during which electricity and diesel are the two major forms of NE used, respectively. Sensitivity analysis showed that the distance over which the pellets are transported affects the cost of NE significantly. Therefore the location of the terminal market and the site where wood resources are available are crucial to saving diesel.