A framework to analyze emissions implications of manufacturing shifts in the industrial sector through integrating bottom-up energy models and economic input/output environmental life cycle assessment models
Kaplan, O., T. Hottle, AND R. Dodder. A framework to analyze emissions implications of manufacturing shifts in the industrial sector through integrating bottom-up energy models and economic input/output environmental life cycle assessment models. EPA 2017 Emissions Inventory Conference, Baltimore, MD, August 14 - 18, 2017.
As emissions reductions are desired in end-use sectors –commercial/residential technologies and light- and heavy-duty vehicles – the corresponding changes in fuel use and technologies can lead to shifts in the upstream production processes. These “upstream” emissions can be associated with changes in fuel production, transport and distribution and/or changes in the manufacturing of technologies. Many of these upstream emissions changes occur in the industrial sector, where there can be shifts in both the demands for manufactured goods as well as technological change in how those good are produced. Capturing both demand changes and technological change within the industrial sector is challenging. One example of potential upstream energy and emissions changes due to end-use energy technologies is that of vehicle mass reduction (VMR) for light-duty vehicles. Automobile manufacturers are using VMR (also called “lightweighting”) of light duty vehicles as one of many strategies to improve fuel economy and reduce greenhouse gas (GHG) emissions. As manufacturers shift toward materials such as higher strength steel, aluminum alloys, magnesium alloys and composite materials such as carbon fiber reinforced plastics, there may be shifts in the relative demand for these materials as well changes in their production processes, efficiency, and location. These changes will affect the emissions associated with these upstream sectors. Beyond the changes in air emissions, there may also be broader environmental impacts (water, material management) due to shifts in both energy (electricity and fuel) use as well as resource consumption for materials production. This analysis utilizes a scenario framework to look at the emissions changes and corresponding environmental impacts. It also contributes to FY17 product under SEM1.3.
Future year emissions depend highly on economic, technological, societal and regulatory drivers. A scenario framework was adopted to analyze technology development pathways and changes in consumer preferences, and evaluate resulting emissions growth patterns while considering future uncertainty. The framework integrates EPA’s MARKet ALlocation (MARKAL) energy systems optimization model with an economic Input-Output (I/O) Life Cycle Assessment model. The EPAUS9r database, utilized with the MARKAL model, includes technologies to represent the U.S. energy system from resource extraction, process and conversion technologies to convert resources into useful energy, to end-use technologies for meeting demands. The demands for goods and services are represented exogenously in MARKAL. It is important to characterize these exogenous inputs appropriately, especially for the industrial sector as energy and emissions outlooks are driven by it. An economic I/O model of the U.S. economy can provide variations in demand and the share of consumer income expended on a given good when a change in input requirements (e.g., energy intensity or a structural change in how this good is made) occurs. Linking an I/O model with MARKAL facilitates analysis of changes in technological progress and consumer preferences in a systematic manner. The framework will then be extended to track life cycle emissions associated with a good. A case study on upstream raw material manufacturing shifts induced by vehicle mass reduction activities in the automotive-industry will be used to illustrate the framework. The study will analyze life cycle emissions and economic implications of switching from steel based materials to aluminum based materials in automotive industry.