Indirect fuel use change (IFUC) and the lifecycle environmental impact of biofuel policies

A common assumption in lifecycle assessment (LCA) based estimates of greenhouse gas (GHG) benefits (or costs) of renewable fuel such as biofuel is that it simply replaces an energy-equivalent amount of fossil fuel and that total fuel consumption remains unchanged. However, the adoption of renewable fuels will affect the price of fuel and therefore affect total fuel consumption which, may increase or decrease depending on the policy regime and market conditions. Using a representative two-region model of the global oil market in which, one region implements a domestic biofuel mandate and the other does not, we show that the net change in global fuel consumption due to the policy, which we term indirect fuel use change (IFUC), can have a significant impact on the net GHG emissions associated with biofuel. If LCA-based regulations are designed to account for indirect emissions such as indirect land use change, then we argue that IFUC emissions cannot be ignored. Our work also shows how different policies can affect the environmental impact from adopting a given clean technology differently.     

Life cycle simulation system as an evaluation platform for multitiered circular manufacturing systems

A life cycle simulation (LCS) is a powerful tool for evaluating the life cycle scenarios of circular manufacturing. Although many LCSs have been developed so far, they were specific to particular scenarios and products. Therefore, we developed a general-purpose LCS system that can be used to evaluate various life cycle scenarios including multiple circulation paths such as closed-loop and cascade reuse and recycling. This system is useful for developing effective circular manufacturing systems with proper life cycle options. We applied it to a closed-loop and cascade reuse of lithium-ion batteries of electric vehicles in order to demonstrate its effectiveness.     

Integration of product entropy and LCA to screen the potential environmental impacts of complex product systems at the end-of-life stage

Applying life cycle assessment (LCA) early in the development of technologies is essential to anticipate potential unforeseen environmental consequences. Modelling the lifecycle of a complex product is nevertheless challenging, as the data required is usually scarce. The approach presented in this paper integrates product entropy into end-of-life modelling for LCA. This enables anticipating the fate of a product after its end-of-use leading to a more realistic allocation of environmental impacts. The approach is demonstrated for the case study of recycling traction batteries with emerging traction battery cell chemistries.     

PDM系统的生命周期管理

PDM是CIMS领域的一项重要技术,PDM系统的生命周期管理体现的是产品从概念形成、初步设计到制造维护直至报废的过程。首先简介PDM的产生背景和产品生命周期管理(PLM)的理念,并描述了PDM的层次结构;给出了PLM体系结构、创建时与运行时模型和生命周期执行服务;最后给出了PLM的实现实例。     

产品数据动态管理模型研究

产品信息及其相关过程的复杂性是产品数据管理的难点所在。本文根据产品数据环境这一特点，提出数据对象、对象关系以及处理数据的过程是产品数据管理的核心内容。研究了产品数据对象间关系的描述方法，引入对象生命周期法的概念，深入分析了对象生命周期法及过程描述法的区别，并给出了将二者结合起来共同描述产品数据动态性的方法。     

面向PLM的产品设计资源集成系统

通过分析产品生命周期管理（PLM）的思想并结合制造企业现状和未来发展趋势,设计了面向PLM的产品设计资源集成系统方案。在设计时分别建立实体、功能和流程的模型,并在此基础上建立协同BOM模型、系统集成模型以支持产品导向设计管理,分割流程模型以支持设计各阶段协同管理。通过AOP设计方法建立与模型对应的系统体系架构,实现系统的柔性和持续化发展。     

中国建筑幕墙行业应尽快推行BIM

探讨了建筑信息模型(BIM)的概念、技术特点、设计的核心理念,简要介绍了BIM案例,BIM为整个建筑幕墙行业带来全新的启示,是一次建筑业信息技术的革命,中国建筑幕墙行业应尽快推行BIM.     

Lifecycle impacts of natural gas to hydrogen pathways on urban air quality

In this paper we examine the potential air quality impacts of hydrogen transportation fuel from a lifecycle analysis perspective, including impacts from fuel production, delivery, and vehicle use. We assume that hydrogen fuel cell vehicles are introduced in a specific region, Sacramento County, California. We consider two levels of market penetration where 9% or 20% of the light duty fleet are hydrogen fuel cell vehicles. The following three natural gas to hydrogen supply pathways are assessed in detail and compared in terms of emissions and the resulting changes in ambient air quality: (1) onsite hydrogen production; (2) centralized hydrogen production with gaseous hydrogen pipeline delivery systems; and (3) centralized hydrogen production with liquid hydrogen truck delivery systems. All the pathways examined use steam methane reforming (SMR) of natural gas to produce hydrogen. The source contributions to incremental air pollution are estimated and compared among hydrogen pathways. All of the hydrogen pathways result in extremely low contributions to ambient air concentrations of _NOx${\mathrm{NO}}_x$, CO, particulates, and _SOx${\mathrm{SO}}_x$, typically less than 0.1% of the current ambient pollution for both levels of market penetration. Among the hydrogen supply options, it is found that the central SMR with pipeline delivery systems is the lowest pollution option available provided the plant is located to avoid transport of pollutants into the city via prevailing winds. The onsite hydrogen pathway is comparable to the central hydrogen pathway with pipeline systems in terms of the resulting air pollution. The pathway with liquid hydrogen trucks has a greater impact on air quality relative to the other pathways due to emissions associated with diesel trucks and electricity consumption to liquefy hydrogen. However, all three hydrogen pathways result in negligible air pollution in the region.     

Assessing social impacts in a life cycle perspective—Lessons learned

In our globalised economy, important stakeholder groups nowadays hold companies responsible for the social impacts they cause in their product chain through activities like child labour, corruption or discrimination of employees. Many companies thus see themselves in need of a tool which can help them make informed decisions about their social impacts throughout the life cycle of their products. The paper presents lessons learned from four years of work with industry on development of a methodology for Social Life Cycle Assessment and implementation in the industrial product chain. The Social LCA methodology supplements the traditional environment-oriented LCA and the life cycle costing tools in support of sustainability management addressing all three pillars of sustainability: people, planet and profit.     

Integration of a service CAD and a life cycle simulator

This paper proposes ISCL, Integrated Service CAD and Life cycle simulator. ISCL plays the role of CAD/CAE tools for product design in Product Service Systems (PSSs) design. In ISCL, the service CAD supports systematic generation of alternative PSSs based on service modeling, and the life cycle simulator analyzes their economic and environmental performances. The current study applies ISCL to the design of a PSS that includes functional upgrading service of a product, whose life cycle costs are sensitive to both its functional obsolescence and physical deterioration. Performances of alternative PSSs are investigated under different market and technology conditions.