| |  |  |  | MS and Ph.D. Dissertations
Below is a list of MS and PhD theses completed by students in the Green Design Institute. If interested in copies, please contact the authors directly.
2008 | 2007 | 2006 | 2005 | 2004 | 2003 | 2001 | 1999 | 1998 | 1997 | 1996 | 1995
2008 Dissertations
A Life-Cycle Approach to Technology, Infrastructure and Climate Policy Decision-Making: Transitioning to Plug-In Hybrid Electric Vehicles and Low-Carbon Electricity, Constantine Samaras, 2008
In order to mitigate the most severe effects of climate change, large global reductions in the current levels of anthropogenic greenhouse gas (GHG) emissions are required in this century to stabilize atmospheric carbon dioxide (CO2) concentrations at less than double pre-industrial levels. The Intergovernmental Panel on Climate Change (IPCC) fourth assessment report states that GHG emissions should be reduced to 50-80% of 2000 levels by 2050 to increase the likelihood of stabilizing atmospheric carbon dioxide (CO2) concentrations. In order to achieve the large GHG reductions by 2050 recommended by the IPCC, a fundamental shift and evolution will be required in the energy system.
Because the electric power and transportation sectors represent the largest GHG emissions sources in the United States, a unique opportunity for coupling these systems via electrified transportation could achieve synergistic environmental (GHG emissions reductions) and energy security (petroleum displacement) benefits. Plug-in hybrid electric vehicles (PHEVs), which use electricity from the grid to power a portion of travel, could play a major role in reducing greenhouse gas emissions from the transport sector. However, because GHG emissions from PHEVs depend on the electricity source that is used to charge the battery, meaningful GHG emissions reductions with PHEVs are conditional on low-carbon electricity sources. Power plants and their associated GHGs are long-lived, so decisions made regarding new electricity supplies within the next ten years will affect the potential of PHEVs to play a role in a low-carbon future in the coming decades. This thesis investigates the life cycle engineering, economic, and policy decisions involved in transitioning to PHEVs and low-carbon electricity.
The government has a vast array of policy options to promote low-carbon technologies, some of which have proven to be more successful than others. This analysis uses a hybrid life cycle assessment to evaluate options and opportunities for large GHG reductions from plug-in hybrids. After the options and uncertainties are framed, this work uses engineering economic analysis to evaluate the actions required for adoption of PHEVs at scale and the implications for low-carbon electricity investments. This work concludes with an examination of what lessons can be learned for climate, innovation, and low-carbon energy policies from the evolution of wind power from an emerging alternative energy technology to a utility-scale power source. Policies to promote PHEVs can take lessons learned from the successes and challenges of wind powers development to optimize low-carbon energy policy and going forward.
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Alternative Transportation Fuels: Infrastructure Requirements and Environmental Impacts for Ethanol and Hydrogen, Heather Wakeley, 2008
This dissertation evaluates infrastructure requirements for ethanol and hydrogen as alternative fuels. It begins with an economic case study for ethanol and hydrogen in Iowa. A large-scale linear optimization model is developed to estimate average transportation distances and costs for nationwide ethanol production and distribution systems. Environmental impacts of transportation in the ethanol life cycle are calculated using the Economic Input-Output Life Cycle Assessment (EIO-LCA) model. An EIO-LCA Hybrid method is developed to evaluate impacts of future fuel production technologies. This method is used to estimate emissions for hydrogen production and distribution pathways.
Results from the ethanol analyses indicate that the ethanol transportation cost component is significant and is the most variable. Costs for ethanol sold in the Midwest, near primary production centers, are estimated to be comparable to or lower than gasoline costs. Along with a wide range of transportation costs, environmental impacts for ethanol range over three orders of magnitude, depending on the transport required. As a result, intensive ethanol use should be encouraged near ethanol production areas.
Fossil fuels are likely to remain the primary feedstock sources for hydrogen production in the near- and mid-term. Costs and environmental impacts of hydrogen produced from natural gas and transported by pipeline are comparable to gasoline. However, capital costs are prohibitive and a significant increase in natural gas demand will likely raise both prices and import quantities. There is an added challenge of developing hydrogen fuel cell vehicles at costs comparable to conventional vehicles.
Two models developed in this thesis have proven useful for evaluating alternative fuels. The linear programming models provide representative estimates of distribution distances for regional fuel use, and thus can be used to estimate costs and environmental impacts. The EIO-LCA Hybrid method is useful for estimating emissions from hydrogen production. This model includes upstream impacts in the LCA, and has the benefit of a lower time and data requirements than a process-based LCA.
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Trade, Consumption, and Climate Change: An Input-Output Study of the United States, Christopher Weber
The previous decade of rapid globalization has brought substantial changes to the U.S. economy, and at the same time, increasing concern about global climate change has brought it to the forefront of U.S. environmental policy. Climate change, like most environmental problems, can be traced back through complex pathways to consumer demand for goods and services, and globalization has further increased the physical and mental distance between consumption and the environmental consequences of production. This work brings together concepts of international trade, consumption, and climate change to analyze the climate impacts of American consumption and trade.
Two broad analyses, one at the economy level and one at the individual household level, are followed by two case studies on specific commodities: food and electronics.We find that a rising proportion (13-30% in 2004) of the CO2 impacts of U.S. consumption are taking place outside of the geographical boundaries of the U.S., and importantly, that the proportion taking place outside the U.S. is increasingly taking place in countries which have not adopted strong climate policies, with around 75% of emissions in US imports taking place in non-Annex B parties to the Kyoto Protocol. This is especially true for electronics, where consumption is consistently increasing, product turnover is very high, and production is particularly concentrated in a small set of developing nations. Food, despite consumer worries about the safety and wisdom of its increasingly global supply chains, remains mostly sourced in the US, though a high-impact category for climate change nonetheless, due both to high transportation and production impacts.
International trade has several policy consequences for climate change—it has been proposed as both a problem, via “leakage” of emissions to developing countries, and a potential solution through coercive or cooperative avenues. Coercive policies such as carbon tariffs, though seemingly an effective way to protect competitiveness and increase participation in global climate frameworks, have several disadvantages including missing a large share of emissions embodied in trade and potentially being both illegal and ineffective due to counteractions. Utilizing global supply chains and trade through cooperative actions such as tariff reduction, clean development programs, and technologytransfer could solve many of the political and policy issues of coercive actions and climate policy in general.
Contact:
Christopher Weber
Assistant Research Professor
Department of Civil and Environmental Engineering
Carnegie Mellon University
clweber@andrew.cmu.edu
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2007 Dissertations
Demand for electricity is expected to increase in the next 25 years. Currently, 50% of the electricity generated in the U.S. is produced using coal. Although natural gas has traditionally been used by the commercial, industrial and residential sector, demand for natural gas for electricity generation has increased in the past decade and this growth is expected to continue in the next 25 years. Since demand is growing but North American supply is expected to remain constant, alternative sources of natural gas will need to be developed. LNG has been identified as one alternative, and plans to increase imports of this fuel are underway. In addition, synthetic natural gas could be produced from coal to meet some of the increasing demand for natural gas.
The demand for natural gas by the transportation sector is currently negligible, but worldwide interest on natural gas-derived transportation fuels (such as natural gas based Fischer-Tropsh Liquids and Compressed Natural Gas) is increasing. The U.S. could either produce these fuels internally, requiring larger imports of LNG, or import them from natural gas-rich countries. Alternatively, the U.S. could produce transportation fuels from coal. Although non-existent in 2005, by 2030 coal-to-liquid-fuel producers are expected to consume as much coal as coke plants. Thus, the production of transportation fuels is an additional end-use where coal and natural gas could compete as the fuel of choice.
The goal of this research is to compare coal and natural gas for use by the electric power sector and for the production of transportation fuels in the next 25 years. This comparison concentrates on the life cycle GHG emissions of these fuels. In addition to comparing natural gas and coal to determine which fuel is better suited for each end-use, a comparison of each end-use will also be performed in order to help determine which is a better use of each fuel. Two main results arise from this research. First, it was found that in a future whereadvanced power plant technologies with carbon capture and sequestration are used, coal and globally sourced natural gas could have very similar life cycle GHG emissions. This begs the question of whether investing billions of dollars in LNG/SNG infrastructure will lock us into an undesirable energy path that could make future energy decisions costlier than ever expected and increase the environmental burden from our energy infrastructure. Second, it was found that the use of transportation fuels derived from coal and natural gas will not help the U.S. reduce the GHG emissions associated with the life cycle of transportation fuels, and in a worse case scenario, the use of these alternative fuels could in fact increase these GHG emissions. In addition, it was found that there is high uncertainty associated with the energy security benefits that could be associated with the consumption of transportation fuels derived from coal.
Contact:
Paulina Jaramillo
Post-doctoral researcher
Department of Civil and Environmental Engineering
Carnegie Mellon University
pjaramil@andrew.cmu.edu
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Heavy metals, such as lead, are toxic, yet despite awareness of this toxic- ity, they are used throughout the global economy. Eliminating their use would reduce risk, but they have useful physical and chemical properties and suit- able substitutes have proven difficult to find. For example, due to previous investigations of lead's toxicity, it was removed as a gasoline additive in the US and other countries beginning in the 1980s. However every automobile and truck shipped contains a lead-acid battery, and many other products still contain lead. For decision makers, being able to better link the flows and uses of lead with the potential human health and ecotoxicity impacts of its release is an important goal.
This dissertation seeks to contribute to this need by developing methods to dynamically track lead flows throughout the economy, and also to link the flows with eventual impact. This is accomplished by the creation of various mixed-unit input-output models of lead and lead compounds in the US economy, at various levels of aggregation (from 12 to approximately 100 sectors). For the latter, a dynamic lead flow model was created to aid in tracking the flows of lead to various media over a 15 year timeframe, 1990 to 2004. The United States' Toxics Release Inventory (TRI) tracks releases to various media of both lead and lead compounds, and this data is a key input into the methods used. These models allow decision makers to recognize which sectors are the sources of the greatest direct and total lead and lead compound emissions.
Beyond tracking lead flows, this dissertation also links lead flows with impacts. To this end, impact assessment values for lead and lead compounds from two well known impact assessment methods, CalTox and the U.S. Environmental Protection Agency's Tool for the Reduction and Assessment of Chemical and Other Environmental Impacts (TRACI) model, were used. The results of the impact assessment suggest that the parameters of CalTOX, as used in TRACI, may lead to underestimates of the actual concentra- tions of lead in the environment. Thus decision makers focused on lead and other heavy metals should explore other impact assessment methods to ensure that the impacts of these substances are better understood.
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Material flows of heavy metals and other toxic chemicals are of great concern for companies, regulators, researchers and society at large. Understanding how and why we use these toxic chemicals can help us to use them more efficiently. In this thesis I develop a mixed-unit, input-output life-cycle assessment model (MUIO-LCA) capable of tracking cadmium, lead, nickel, and zinc flows among roughly 500 sectors of the U.S. economy.
Flows of cadmium, lead, nickel and zinc commodities are modeled using data provided by the U.S. Geological Survey (USGS) by adding sectors to national input-output accounts developed by the U.S. Bureau of Economic Analysis (B.E.A.). First an aggregate, summary level model based on the B.E.A. 12 by 12 sector monetary input-output tables is introduced and used to explain the method. Then a detailed model is constructed by augmenting the detailed B.E.A. 1997 Benchmark Input-Output make and use tables. The 1997 Benchmark Input-Output Accounts consist of 483 commodities, 491 industries, and 13 final demand sectors. Flows of cadmium, lead, nickel, and zinc were added as an additional 46 commodities, 20 industries, and 10 final demand sectors.
Flows of an additional 103 materials are modeled with use factors developed from U.S.G.S. production and consumption data. These materials include 48 metals, 38 minerals, coal combustion by-products, agricultural products, and wood products. An assessment of the uncertainty in model is presented. This includes a discussion of the error in input-output life-cycle assessment models as well as an analysis of uncertainty in model parameters. Because of the large data requirements for the creation of the mixed-unit make and use tables, definition of distributions for each data point was not possible. Uncertainty in the use factors for the additional 103 materials was estimated by calculating these factors using consumption data as well as production data for the period 1997 to 2004.
To demonstrate MUIO-LCA the material use associated with the production of an average automobile is modeled. Results are compared to those of a comprehensive, process-based inventory of the material content and supply chain material use for a generic U.S. family sedan performed by the USAMP LCA Project ('98). Results for the lead content of an average car were compared to an inventory provided by the Clean Car Campaign (Trumble '98). This case study highlighted the need for care in interpreting the results of the MUIO-LCA model. MUIO-LCA provides information about commodities consumed directly and throughout the supply chain of a product. While these values provide guidance on the possible material content of a product itself, they also include the tangential use of materials consumed in processes but not included in products. An exploratory examination of the material intensity of the 483 monetary transaction commodities in the MUIO-LCA model is performed using the total requirements matrix. Results are summarized for the top 10 sectors for material use of metal commodities included in the MUIO-LCA model as well as the 103 additional materials.
Contact:
Troy Hawkins
trh@alumni.cmu.edu
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This research uses a life cycle assessment (LCA) framework to create a more specific and accurate estimate of the environmental impacts of construction processes. The construction industry is spatially and economically diverse, yet fragmented because it is always changing, occurring everywhere, and dependent upon a variety of specialized contractors. Because the construction industry is so complex, modeling traditional construction processes is required in order to understand the specific environmental implications of these activities; this goal would be best achieved with the process LCA approach, though process LCAs are data intensive and time consuming given the “made to order” nature of each construction project. Conversely, the input-output LCA approach allows for a more inclusive view of the construction industry (i.e., not just traditional on-site construction activities), and can be used to identify which processes should be of principal concern. A combination of both approaches allows the strengths of each to be used to the best advantage. Consequently, a hybrid LCA framework produces a comprehensive analysis that includes the economy-wide effects of construction while addressing specific on-site construction activities.
The input-output-based hybrid LCA framework selected for this research is based on Carnegie Mellon University’s (CMU) Economic Input-Output Life Cycle Assessment (EIO-LCA) modeling tool. The input-output-based hybrid was created by combining a new “Hybrid” feature that uses the EIO-LCA interface and updated and reformulated environmental effects vectors for EIO-LCA’s thirteen construction sectors. The final stage of this research models a variety of construction case studies on the input-output-based hybrid LCA framework to demonstrate its broad applicability.
The hybrid LCA model for construction processes detailed here is designed help decision-makers make more informed decisions regarding the construction industry, adding environmental quality and sustainable development as goals instead of unintentional benefits. The model’s focus on construction site and ancillary support activities helps identify opportunities for improvement in the construction industry that may otherwise be missed and provides a holistic assessment that identifies priority areas for future research into the environmental impacts of construction processes.
Contact:
Aurora L. Sharrard, PhD
Research Manager
Green Building Alliance
333 East Carson St., Suite 331
Pittsburgh, PA 15219
aurorasharrard@yahoo.com
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The electricity industry is extremely important to both our economy and our environment: we would like to examine the economic, environmental and policy implications of both future electricity technologies and the interaction of this industry with the rest of the economy. However, the tools which currently exist to analyze the potential impacts are either too complex or too aggregated to provide this type of information.
Because of its importance, and the surprising lack of associated detail in the inputoutput model of the U.S. economy, the power generation sector is an excellent candidate for disaggregation. This work builds upon an existing economic inputoutput tool, by adding detail about the electricity industry, specifically by differentiating among the various functions of the sector, and the different means of generating power. We build a flexible framework for creating new industry sectors, supply chains and emission factors for the generation, transmission and distribution portions of the electricity industry. In addition, a systematic method for creating updated state level and sector generation mixes is developed.
The results of the analysis show that the generation assets in a region have a large impact on the environmental impacts associated with electricity consumption, and that interstate trading tends to make the differences smaller. The results also show that most sector mixes are very close to the U.S. average due to geographic dispersion of industries, but that some sectors are different, and they tend to be important raw material extraction or primary manufacturing industries. Further, in scenarios of the present and future, for electricity and for particular products, results show environmental impacts split up by generation type, and with full supply chain detail. For analyses of the current electricity system and products, economic and environmental results match well with external verification sources, but for analyses of the future, there is significant uncertainty. Future work in this area must address the inherent uncertainty of using an economic model to generate emissions values, although the framework of the model allows for infinite expansion and adjustment of assumptions.
Contact:
Joe Marriott
jmm185@pitt.edu
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2006 Dissertations
Reduction of the negative environmental and human health externalities resulting from both the electricity and transportation sectors can be achieved through technologies such as clean coal, natural gas, nuclear, hydro, wind, and solar photovoltaic technologies for electricity; reformulated gasoline and other fossil fuels, hydrogen, and electrical options for transportation. Negative externalities can also be reduced through demand reductions and efficiency improvements in both sectors. However, most of these options come with cost increases for two primary reasons: (1) most environmental and human health consequences have historically and are currently excluded from energy prices; (2) fossil energy markets have been optimizing costs for over 100 years and thus have achieved dramatic cost savings over time. Comparing the benefits and costs of alternatives requires understanding of the tradeoffs associated with competing technology and lifestyle choices.
Bioenergy advocates propose its use as an alternative energy resource for electricity generation and transportation fuel production, primarily focusing on ethanol. These advocates argue that bioenergy offers environmental and economic benefits over current fossil energy use in each of these two sectors as well as in the U.S. agriculture sector. However, estimates of bioenergy resource reveal that bioenergy is only capable of offsetting a portion of current fossil consumption in each sector. As bioenergy is proposed as a large-scale feedstock within the United States, a question of “best use” of bioenergy becomes important. Unfortunately, bioenergy research has offered very few comparisons of these two alternative uses. This thesis helps fill this gap.
This thesis compares the economics of bioenergy utilization by a method for estimating total financial costs for each proposed bioenergy use. Locations for potential feedstocks and bio-processing facilities (co-firing switchgrass and coal in existing coal fired power plants and new ethanol refineries) are estimated and linear programs are developed to estimate large-scale transportation infrastructure costs for each sector. Each linear program minimizes required bioenergy distribution and infrastructure costs. Truck and rail are the only two transportation modes allowed as they are the most likely bioenergy transportation modes. Switchgrass is chosen as a single bioenergy feedstock. All resulting costs are presented in units which reflect current energy markets price norms (¢/kWh, $/gal). The use of a common metric, carbon-dioxide emissions, allows a comparison of the two proposed uses. Additional analysis is provided to address aspects of each proposed use which are not reflected by a carbon-dioxide reduction metric. Using switchgrass as an electricity generation feedstock offers more than twice the amount of carbon-dioxide emission reductions as using switchgrass as an ethanol feedstock (370 versus 160 million short tons per year respectively; representing 14% and 12% of electricity and transportation sector annual CO2 emissions). Total costs, including capital, labor, feedstock, and transportation, is more certain for electricity production than for ethanol; 20 - 45 $/ton CO2 mitigated versus free - 80 $/ton CO2 mitigated respectively. In both cases, mitigation cost is a variable of fossil energy costs. Coal price are very stable as compared to crude oil prices and therefore, more risk is inherent in ethanol economics than in electricity economics.
Additional analysis comparing life-cycle benefits and burdens though full-cost accounting methods also favors bioenergy for electricity production. Agricultural impacts are neutral, while criteria pollutants increase with ethanol use and decrease with bioenergy electricity production. Moreover, ethanol use could cause an increase in groundwater toxicity, a risk that is not associated with electricity production. Considering other available alternative technologies, switchgrass co-firing in existing coal power plants is the least costs retrofitting option available to existing coal fired power plants wishing to lower their carbon emissions. Plug hybrids offer increased system efficiencies over current gasoline-propulsion systems, thereby lowering criteria pollutants and greenhouse gas emissions all at a cost less than or comparable to ethanol. However, shifting transportation energy demands into the United States’ antiquated electrical grid will require large-scale electricity infrastructure investments. The economic impact of a large-scale transfer of energy from petroleum to electricity should be a topic of future research.
Contact
William R. Morrow, III, Ph.D., P.E.
Senior Consultant
Energy and Environmental Economics, Inc.
101 Montgomery Street, Suite 1600
San Francisco, CA 94104
415-391-5100 (phone)
415-391-6500 (fax)
bill@ethree.com
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2005 Dissertations
Historically, the cement industry has been challengedwith the requirement of improving its manufacturing process while reducing itsfootprint on the environment. Atthe same time, global competition poses more challenges to improving the bottomline of the business. Research and development of pollution abatementtechnology for cement manufacturing is key for effectively operating in this newenvironment. These new technological advancements compete against establishedtechnologies when cement manufacturers evaluate different pollution preventionstrategies.
This research developed a quantitative tool tobenchmark various technologies available to produce Portland cement in theUnited States. The model “Technology Change Evaluation for the Cement Industry”(TCECI) was developed to achieve this goal considering a full cost approach.Several production scenarios were designed and evaluated to represent the currentand potential future conditions of the cement industry in the United States.The decision making process to select the Best Available Technology (BAT) forcement manufacturing in the United States considered the minimization of theprivate and the total cost (i.e., including private and social costs) underdifferent multi-pollutant approaches. One of these approaches considered theminimization of carbon dioxide emissions from the calcination of raw materialsand the combustion of the fuel from cement manufacturing. These emissions wereestimated for each production scenario considering an emission tax scheme andan emission allowance trading program.
The most relevant result obtained from thisresearch is the integration of environmental and social aspects of cementmaking into the current decision making process for technology change. Thisintegration led to production alternatives with improved environmental, socialand economic performance. Additionally, the results of this research indicatethat the current technology mix for cement manufacturing in the United Stateslimits the feasibility of new cement plants when considering the full costapproach. However, the results of the analysis indicate that the implementationof BAT in existing plants (under the conditions and characteristics assumed bythe TCECI model) improves their overall economic and environmental performance.The reduction estimated for the full cost ranged from 19% to 22% whilecomparing the baseline scenario for the year 2004 with a multipollutant approach (i.e., in 2004dollars per ton of clinker, $50 –production scenario No. 8- and $48 –productionscenario No. 7- versus $61 from the baseline scenario).
Finally, the results also indicate that within thelimited sample of production scenarios considered there is large variability inthe estimated uncertainty of the costs associated with the production ofcement, the air emissions reported from the production process and theperformance data from available technologies for pollution control and processoptimization. The differences of the social costs estimated for each productionscenario were found statistically more significant when considering the effectof the use of alternative fuels (i.e., tire fuel instead of coal) than the effectof a more stringent regulatory environment.
Since performance data for control technologies andair emissions are becoming more important to private and public policy decisionmaking, it is recommended that the Environmental Protection Agency and the cementindustry treat uncertainty explicitly, by means of adopting standardizedmeasurement and reporting methodologies for air emissions among other relevantmeasures.
Contact
Jose Luis Aguirre
jlag04@gmail.com
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The U.S. electricity industry is currently experiencing and adapting to enormous change including concerns related to security, reliability, increasing demand, aging infrastructure, competition and environmental impacts. Decisions that are made over the next decade will be critical in determining how economically and environmentally sustainable the industry will be in the next 50 to 100 years. For this reason, it is imperative to look at investment and policy decisions from a holistic perspective, i.e., considering various time horizons, the technical constraints within the system and the environmental impacts of each technology and policy option from an economic and environmental life cycle perspective.
This thesis evaluates the cost and environmental tradeoffs of current and future electricity generation options from a life cycle perspective. Policy and technology options are considered for each critical time horizon (near-, mid-, and long-term). The framework developed for this analysis is a hybrid life cycle analysis which integrates several models and frameworks including process and input-output life cycle analysis, an integrated environmental control model, social costing, forecasting and future energy scenario analysis.
The near-term analysis shows that several recent LCA studies of electricity options have contributed to our understanding of the technologies available and their relative environmental impacts. Several promising options could satisfy our electricity demands. Other options remain unproven or too costly to encourage investment in the near term but show promise for future use (e.g. photovoltaic, fuel cells). Public concerns could impede the use of some desirable technologies (e.g. hydro, nuclear). Finally, less tangible issues such as intermittency of some renewable technologies, social equity and visual and land use impacts, while difficult to quantify, must be considered in the investment decision process.
Coal is a particularly important fuel to consider in the U.S. and is the main focus of this thesis. A hybrid life cycle analysis including the use of process level data, Economic Input-Output Life Cycle Assessment (EIOLCA) and the Integrated Environmental Control Model (IECM) quantify a range of potential impacts for new power plants. This method provides a more complete and consistent basis for comparing different technologies. While Integrated Coal Gasification Combined Cycle (IGCC) technology has clear environmental benefits for bituminous coals over conventional pulverized coal plants, the advantages are less clear for the lower ranked coals at present. Near-term implementation of this technology is hampered by concerns about its reliability and performance. A full scale U.S. installation of this technology would settle the performance concerns while more stringent emissions standards would increase its value. In the mid-term analysis, this thesis explores alternative methods for transport of coal energy. A hybrid life cycle analysis is critical for evaluating the cost, efficiency and environmental tradeoffs of the entire system. If a small amount of additional coal is to be shipped, current rail infrastructure should be used where possible. If entirely new infrastructure is required, the mine mouth generation options are cheaper but have increased environmental impact due to the increased generation required to compensate for transmission line losses. Gasifying the coal to produce methane also shows promise in terms of lowering environmental emissions.
The long-term analysis focuses on the implications of a high coal use future. This scenario analysis focuses on life cycle issues and considers various generation and control technologies. When advanced technologies such as gasification with carbon capture and sequestration are used, emissions during generation decrease to a level where environmental discharges from extraction, processing and transportation become the dominant concern. The location of coal, coal composition and mining method are important in determining the overall impacts. Coal is an inherently dirty fuel. However, for the next half century, coal is likely to play a major role in electricity generation. In deciding how much coal to use, the U.S. must understand the cost and environmental implications of the technologies available, including the whole life cycle of the fuel and the facilities used from extraction, transport, generation, and use or disposal of by products.
Contact:
Dr. Joule A. Bergerson
University of Calgary
Chemical and Petroleum Engineering
2500 University Drive NW, Room 602
Earth Sciences Building
Calgary, Alberta T2N 1N4
Canada
jbergers@ucalgary.ca
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Life Cycle Assessment of Residential Buildings, Luis Ochoa, 2005
Residential building construction represented about 4.2% ofthe US Gross Domestic Product in 2000, and residences consumed nearly 20% oftotal US energy consumption. However, design and construction of residential buildings is often notconducted with an analysis of the life cycle costs and environmental impacts. In this paper, we outline an approachto a comprehensive life cycle analysis for residences, using the results of atypical construction cost estimate to map into tools for environmental lifecycle assessment (using the Carnegie Mellon economic input-output life cycleassessment model) and for resources required during the use phase of residences(using the DOE Energy Saver model). In essence, material costs are mapped into input-output sectors and theEIO-LCA model applied to assess environmental impacts. Similarly, operating inputs such aselectricity or natural gas are estimated from the Home Energy Saver model andmapped into EIO-LCA sectors. Theresult of using our toolset is a full life cycle assessment based upon theconstruction cost estimate.
Contact
Luis Ochoa
luis1a1@yahoo.com
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2004 Dissertations
Using Life Cycle Assessment to Inform Nanotechnology Research and Development, Shannon Lloyd, 2004
By reducing the energy and materials required to provide goods and services, nanotechnology has the potential to provide more appealing products while improving environmental performance and sustainability. However, while nanotechnology offers great potential, it is unlikely to be the first entirely benign technology. My hypothesis is that a technological push towards greater investment in nanotechnology without a commensurate consideration of the net environmental benefits will inevitably lead to cases where the nanotechnology substitute is inferior to the product or process replaced. Whether and how soon the promise of improved environmental quality could be realized depends on phrasing life cycle questions during research and development and pursuing commercialization intelligently.
Efforts have been initiated to develop a fundamental understanding of the behavior of nanotechnology-based materials in natural systems and their influence on biological systems. This understanding will improve the ability to project the direct environmental and health effects of these materials. To obtain a complete picture, it is also necessary to consider life cycle and sustainability implications on nanotechnology-based products. I present a framework employing quantitative analysis to evaluate projected nanotechnology-based products. I use technology scenarios and prospective hybrid life cycle assessment to estimate the economic and environmental life cycle implications of two projected nanotechnology-based products. In the case of using nanocomposites in light-duty vehicle body panels, the ability to disperse nanoscale particles in polymers would reduce vehicle weight thereby improving fuel economy. In the case of nanofabricated catalysts, the ability to position and stabilize platinum-group metal particles in automotive catalyst would reduce the amount of platinum-group metal required to meet emissions standards thereby reducing mining and refining activities. For each application, I compare a conventional product to its nanotechnology-based substitute to assess whether the nanotechnology substitute can be cost-effective and improve environmental quality.
Life cycle assessment is typically used to estimate the resource and environmental implications associated with existing products. Changing a product to reduce its environmental impact after the product has been developed can cost orders of magnitude more than making the change during research and development. As shown here, policy makers and industry can identify technology scenarios and employ prospective life cycle assessment during early research and development to evaluate future products and emerging technologies. The ability to evaluate life cycle implications of alternative courses of action during research and development improves the ability to evaluate tradeoffs, optimize products for all aspects of life cycle performance, and make more strategic R&D choices. A more informed understanding of the commercial, societal, and technological possibilities and its consequences will enable better decisions in regards to the selection, development, and commercialization of nanotechnology.
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1. The data from California energy crisis of 2000 suggests that the largest departures of observed electricity prices from the estimates of the competitive price occur when demand approaches market capacity. This paper studies models of unilateral and collusive market power applicable to electricity markets. Both suggest a unique mechanism explaining the increase of the price-cost margin with demand. The empirical test of these models provides more evidence for unilateral market power than for behavior suggesting tacit collusion.
2. In order to preserve the stability of electricity supply, electric generators have to provide ancillary services in addition to energy production. Hydro generators are believed to be the most efficient source of ancillary services because of their good dynamic flexibility. This paper studies optimal operation decisions for river dams and pumped storage facilities operating in markets for energy and ancillary services as well as the change in the water shadow price in presence of ancillary services markets. The analysis is applied to valuation of the ancillary services provided by hydro resources in the Tennessee Valley Authority. A simulation of ancillary services markets shows that TVA’s hydro resources providing ancillary services can allow for substantial savings in total costs of energy provision. Optimal hydro scheduling in markets for energy and ancillary services increases the value of TVA’s hydro resources by 9% on average and up to 26% for particular units. As a result of hydro participation in ancillary services markets water shadow prices of river dams drop significantly allowing for tightening hydro constraints in favor of other water uses.
Contact:
Dr. Dmitri Perekhodtsev
LECG
6 Canal Park
Suite 708
Cambridge, MA 02140
DPerekhodtsev@lecg.com
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