This paper presents a method of environmental assessment that incorporates the strengths of ecological footprint and process based life cycle analysis. Like ecological footprint, product ecological footprint delineates between sustainable and unsustainable consumption. The ecological footprint of individual products allows consumers to budget their consumption within this limit. The resolution of product ecological footprint can be scaled, like life cycle analysis, to compare one feature, process, or product against another. This study calculates the product ecological footprint of the generic American automobile using industry life cycle inventory, US statistical data, and data on global ecological capacity. It considers CO2 emissions, mining impacts, and land directly occupied as the major contributors of land use. The conversion of these impact categories to hectares of ecological services was performed using a top down approach, based on global supply. The sources were chosen to produce a lower-bound estimate rather than the true ecological footprint.

Based on this study, the average car owner in the US expends at least 50% (0.8 hectares) of their ecological budget on driving alone. The footprint of a car is dominated fuel efficiency. The actual footprint may range from 30% to over 100% of one's ecological budget, corresponding to fuel efficiencies between 55 mpg and 12 mpg. The ecological footprint of the average automobile is more than 800 times the area it occupies physically. The metric of land communicates environmental impact in an immediate and tangible manner. Land accurately represents the importance of ecological services over resources alone. It is one of few metrics that can compare dissimilar products and processes. Accordingly, product ecological footprint enables consumers to formulate and follow a personal ecological budget. The results of this study are designed to be meaningful to consumers and producers in hopes of provoking societal changes that will push industry towards sustainable design and manufacturing.

Environmental assessment of photovoltaic systems is a rich field, with representations of many technologies, regions and methodologies. This paper discusses some of the factors that strongly affect the outcomes of studies, encourages detailed reporting of normalization parameters and scope, and discusses a cradle to grave framework for benchmarking life cycle assessments of photovoltaic systems.

Energy use is an important metric of environmental impact and manufacturing efficiency. However, a major component of energy analysis has yet to permeate life-cycle analysis methodology: the energy use associated with human labor. This paper presents a straightforward method of estimating the energy demands of an hour of industrial labor based on readily available national statistics. In the United States, this estimate yields 30 MJ of primary energy use per worker-hour (EPWH). These results can be applied to inform and expand the application of process-based and hybrid economic input-output life-cycle assessment.

Life cycle assessment (LCA) is a powerful environmental management and decision- mak- ing tool that has served the needs of many individual and institutional consumers. Using the example of a thin-film amorphous silicon photovoltaic system, this dissertation work adapts life cycle assessment to best meet the design-for-environment needs of producers.

The producer-focused LCA helps to minimize to the environmental impacts of products by (1) identifying opportunities to reduce environmental impacts, (2) tracking and communi- cating the impacts of design changes, and (3) benchmarking the environmental performance of products with respect to other options on the market. To meet these goals, this dissertation introduces and demonstrates two unique life cycle assessment features - facilities integration and scenario functionality.

Facilities integration is a realistic and dynamic method of attributing the impacts of facilities systems to the corresponding process steps. This is important because facilities impacts are otherwise treated as fixed. This features significantly expands design space available to producers for minimizing environmental impacts in manufacturing.

Scenario functionality is a flexible model structure that allows end users to select from and evaluate a number of different technology, manufacturing, implementation, and model scope options. The feature is useful for two main purposes: (1) to analyze and compare any number of life cycle scenarios, and (2) to adapt model assumptions and scope to mimic that of other studies so that their results can be compared more meaningfully.

This dissertation presents the most comprehensive environmental assessment of thin film silicon photovoltaic (PV) systems to date, employing measured process data of unprece- dented resolution. The cumulative energy demand (CED) and global warming potential (GWP) emissions of an example case, in which manufacturing and installation occur in the United States and the scope includes processes from raw materials to recycling at the end of life, are 2.5 GJ/m2 and 202 kg CO2 eq/m2, corresponding to payback times of 23 and 31 months, respectively. Approximately half the total life cycle impacts occur due to down- stream processes, including balance of system components, transportation, and end of life processing.

A set of results, representing a range of values for 17 different manufacturing and system parameters, is used to identify scenarios yielding the fastest and slowest energy and global warming potential payback times. Thirteen of the parameters are evaluated in a sensitivity analysis, showing that the parameters having the greatest influence on the payback times of the system are energy conversion efficiency, system performance ratio, and characteris- tics of electricity offset during the life of the PV system. The characteristics of electricity offset are parameters that are not widely recognized as having such great influence, and if recognized, may persuasively illustrate the advantages of adopting PV and other renewable energy technologies in areas utilizing inefficient or highly polluting energy sources.

Finally, this dissertation presents a robust, top-down methodology for quantifying the environmental impact of a worker-hour of industrial human labor. Labor is a necessary component of any manufacturing system, and a major source of economic and logistical variance, yet is typically omitted as a factor in the environmental impacts of manufacturing systems. The methodology is applied to quantify the energy consumption, global warming potential, and water withdrawals of an industrial worker-hour in the US as 63 MJ, 4.6 kg CO2 eq, and 82 gallons per worker-hour, respectively . Energy and GWP costs per worker-hour are given, including and excluding the effects of international trade, for 20 major manufacturing countries.

Plasmonic imaging lithography (PIL) is a new direct-write lithograghy process based on disk drive technology. Using the benchmark of similarly scaled masked and maskless lithography processes, this paper evaluates the operational energy use of PIL, as a component of manufacturing and environmental impact analysis. This study serves two purposes: to inform the sustainable development of this emerging technology, and to identify PIL as most appropriate for prototyping or highly agile manufacturing of 11 or fewer wafers per design change.

This paper presents an overview of key nanoscale manufacturing technologies, and qualitatively examines their fundamental process requirements with respect to energy demand. The processes requirements are related to semiconductor manufacturing, where applicable, and gaps in our understanding of these processes on the production scale are identified as goals for the research community. Finally, the paper proposes a framework for the systematic analysis of energy use in nanoscale manufacturing processes.

This study is an evaluation of the use and supply of compressed air, which is one of the most expensive energy sources in manufacturing, at Ford Motor Company’s Livonia (Mich.) Transmission Plant. The aim of the study is to make recommendations to improve environmental and economic efficiency in future facilities. This paper presents a quantitative analysis of three compressed air supply patterns—plant air, point of use (POU), and local generation—as alternatives for future compressed air usage. Environmental Value systems(EnVS) tools are employed to analyze the economic and environmental performance of the three alternative supply patterns by using cost of ownership and environmental impact matrices. The results favor local generation over the other two alternatives in terms of economic and environmental considerations.