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Life Cycle Analysis: Coal

Life Cycle Analysis of Coal Exports from the Powder River Basin

Date: 8/4/2016
Contact: Timothy J. Skone, P.E.

The purpose of this study was to compare environmental implications of exporting United States (U.S.) coal resources to Asian markets with respect to alternative global sources of steam coal. This study seeks to evaluate and understand potential environmental consequences of exporting PRB coal compared to global alternative sources of coal. This study was informed by a 10-person industry based Technical Steering Committee to improve the quality of the analysis. The key question addressed by the study: Is there a definitive difference between the life cycle GHG profiles between sourcing coal from the U.S. (PRB), Australia, or Indonesia for Japan, South Korea, or Taiwan? Given the uncertainty in the model parameter values, there is not a definitive difference between the life cycle GHG profiles between sourcing coal from the U.S. (PRB), Australia, or Indonesia for Japan, South Korea, or Taiwan.


Life Cycle Analysis of Coal Exports from the Powder River Basin

Date: 6/15/2016
Contact: Timothy J. Skone, P.E.

This presentation was given at the 2016 Carbon Capture, Utilization, and Storage Conference in June, 2016, and provided the complete technical details behind and the full life cycle impacts of exporting coal from the Powder River Basin in the U.S. to electricity markets in Asia. Key takeaways are the relative large contribution of the transportation of the coal when traveling distance.


Coal-Hybrid Power Systems for the Future Presentation

Date: 12/9/2015
Contact: Robert James

The presentation was presented at the Coal-Gen 2015 Conference on 12/9/15. Coal power generation and consumption have both been on a downward trend for the last six years, based on reduced overall demand and having been supplanted by natural gas-fired power generation. This paper exhibits hybrid energy system concepts that will enable coal to be competitive in today’s electric power market on both a cost and emissions basis. These hybrid system pathways will utilize renewables, biomass, and even waste streams to help coal plants generate power more efficiently, more cost effectively, and with lower emissions than current state-of-the-art.


U.S. Coal Exports – Life Cycle GHG comparison of PRB coal to foreign export competitors in the Asian Market

Date: 10/6/2015
Contact: Timothy J. Skone, P.E.

The purpose of this study was to compare environmental implications of exporting United States (U.S.) coal resources to Asian markets with respect to alternative global sources of steam coal. This study seeks to evaluate and understand potential environmental consequences of exporting PRB coal compared to global alternative sources of coal. This study was informed by a 10-person industry based Technical Steering Committee to improve the quality of the analysis. The key question addressed by the study: Is there a definitive difference between the life cycle GHG profiles between sourcing coal from the U.S. (PRB), Australia, or Indonesia for Japan, South Korea, or Taiwan. Given the uncertainty in the model parameter values, there is not a definitive difference between the life cycle GHG profiles between sourcing coal from the U.S. (PRB), Australia, or Indonesia for Japan, South Korea, or Taiwan. This document was presented at the LCAXV conference in October, 2015.


NETL Fischer-Tropsch Black Box Model

Date: 9/15/2015
Contact: Timothy J. Skone, P.E.

The purpose of the Fischer-Tropsch (F-T) Black Box Model is to allow for the screening of the impacts of F-T finished fuels production based on the input of a unique syngas composition. Utilizing the composition of the raw syngas, the model calculates the following outputs based on a facility sized to produce 50,000 bbl/day of liquid product: CO2 emissions, liquid product flows, required syngas input, and the net export electricity from the facility. NETL completed this model/study for the Connecticut Center for Advanced Technology (CCAT) to provide techno-economic and life cycle analysis modeling support for CBTL alternative jet fuel production, which forms key references to their report to the Defense Logistics Agency (their project sponsor/funder).


NETL Fischer-Tropsch Black Box Model Documentation

Date: 9/15/2015
Contact: Timothy J. Skone, P.E.

The purpose of the Fischer-Tropsch (F-T) Black Box Model is to allow for the screening of the impacts of F-T finished fuels production based on the input of a unique syngas composition. Utilizing the composition of the raw syngas, the model calculates the following outputs based on a facility sized to produce 50,000 bbl/day of liquid product: CO2 emissions, liquid product flows, required syngas input, and the net export electricity from the facility.NETL completed this model/study for the Connecticut Center for Advanced Technology (CCAT) to provide techno-economic and life cycle analysis modeling support for CBTL alternative jet fuel production, which forms key references to their report to the Defense Logistics Agency (their project sponsor/funder).


Comprehensive Analysis of Coal and Biomass Conversion to Jet Fuel: Oxygen Blown, Transport Reactor Integrated Gasifier (TRIG) and Fischer-Tropsch (F-T) Catalyst Configurations Modeled and Validated Scenarios

Date: 9/8/2015
Contact: Timothy J. Skone, P.E.

This study evaluates the technological/process, life cycle environmental, and economic perspective of 20 discreet F-T jet fuel production scenarios. The technological/process model provides a process level evaluation of the 10 alternate CBTL facility scenarios considered in this study. Aspen Plus simulation models for the CBTL facility scenarios were developed to determine the composition and flows of all of the major streams in the plants. These were used to develop conceptual level cost estimates for capital and operating costs for the major process units. NETL completed this study for the Connecticut Center for Advanced Technology (CCAT) to provide techno-economic and life cycle analysis modeling support for CBTL alternative jet fuel production, which forms key references to their report to the Defense Logistics Agency (their project sponsor/funder).


Life Cycle Greenhouse Gas Emissions: Natural Gas and Power Production

Date: 6/15/2015
Contact: Timothy J. Skone, P.E.

This presentation was given at the 2015 Energy Information Administration (EIA) Energy Conference. It discusses the importance of understanding greenhouse gas (GHG) emissions from the power and natural gas sectors, and then goes into more detail on the life cycle GHG emissions from natural gas and from power generation in general.


Coal and Biomass to Liquids (CBTL) Greenhouse Gas Optimization Tool

Date: 3/11/2015
Contact: Timothy J. Skone, P.E.

The purpose of the model is to perform scenario analysis to optimize GHG performance under varies CBTL configurations.  This model expands upon the NETL CBTL Jet Fuel Model by providing the user the ability to choose from three coal types (Illinois No. 6 bituminous coal, Montana Rosebud sub-bituminous coal, or North Dakota Lignite) and three biomass types (Southern pine, switchgrass, or municipal solid waste). The model will also allow the user to adjust the fraction of the captured CO2 that is vented and adjust the overall efficiency of the plant.  The model includes environmental performance data for CBTL plants modeled under the CCAT case studies and two additional NETL studies: Production of Zero Sulfur Diesel Fuel from Domestic Coal: Configurational Options to Reduce Environmental Impact and Cost and Performance Baseline for Fossil Energy Plants Volume 4: Coal-to-Liquids via Fischer-Tropsch Synthesis.


Coal and Biomass to Liquids (CBTL) Greenhouse Gas Optimization Tool Documentation

Date: 3/11/2015
Contact: Timothy J. Skone, P.E.

This report is the user documentation for the NETL CBTL Jet Fuel Model submitted under a separate approval routing. The documentation is intended to accompany the model. The documentation explains how to the use the model. The documentation does not contain any energy analysis findings. NETL completed this model/report as part of a study for the Connecticut Center for Advanced Technology (CCAT) to provide techno-economic and life cycle analysis modeling support for CBTL alternative jet fuel production, which forms key references to their report to the Defense Logistics Agency (their project sponsor/funder).


CBTL Jet Fuel Model

Date: 2/27/2015
Contact: Timothy J. Skone, P.E.

An Excel-based model was developed to allow in-depth user access to the technological process, economic, and life cycle environmental results that were completed in support of this study, for each of the different CBTL jet fuel production scenarios (total of 49 unique result sets when counting both TRIG and EFG scenarios). The CBTL Jet Fuel Model incorporates a stochastic analysis of modeled results, drawing on input statistical distributions for the 17 environmental and 40 economic parameters. A stochastic analysis was performed by using the Palisade Corporation’s @RISK Excel add-in. NETL completed a CRADA with Connecticut Center for Advanced Technology (CCAT) to provide techno-economic and life cycle analysis modeling support for CBTL alternative jet fuel production, which forms key references to their report to the Defense Logistics Agency (their project sponsor/funder).


Cost and Performance Baseline for Fossil Energy Plants - Volume 4: Coal-to-Liquids via Fischer-Tropsch Synthesis

Date: 10/15/2014
Contact: William Summers

This report establishes performance and cost data for coal-to-liquids systems, specifically by means of gasification and Fischer-Tropsch reaction. The analyses were performed on a consistent technical and economic basis to assess the design and financial performance of a commercial-scale coal-to-Fischer-Tropsch liquids facility. The cost and performance data were compiled from published reports, information obtained from vendor quotes and users of the technology, and data from designing and building utility and refining projects.


Life cycle GHG Footprint of a U.S. Energy Export Market for Coal and Natural Gas

Date: 10/7/2014
Contact: Timothy J. Skone, P.E.

This presentation was given at the LCA XIV Conference and shows that the majority of life cycle GHG emissions come from power plants; even the LNG export scenarios, which lose approximately 10% of transported natural gas to parasitic loads, have lower life cycle GHG emissions than the coal scenarios.


Comprehensive Analysis of Coal and Biomass Conversion to Jet Fuel: Oxygen Blown, Transport Reactor Integrated Gasifier (TRIG) and Fischer-Tropsch (F-T) Catalyst Configurations

Date: 2/19/2014
Contact: Timothy J. Skone, P.E.

The Connecticut Center for Advanced Technology (CCAT) has received funding from the Defense Logistics Agency (DLA) Energy to demonstrate how liquid fuel can be produced from coal and meet the Energy Independence and Security Act (EISA) of 2007 greenhouse gas (GHG) requirement for DOD fuel purchases of synthetic fuel. Section 526 of EISA requires that any fuel purchases have a life-cycle CO2 emission less than conventional petroleum fuel. This study evaluates different scenarios for the conversion of coal and biomass to jet fuel using oxygen blown, transport reactor integrated gasifier and Fischer-Tropsch catalyst configurations.


Power Plant Flexible Model

Date: 11/8/2013
Contact: Timothy J. Skone, P.E.

The Power Plant Flexible Model (PPFM) is an Excel-based tool that simulates coal combustion-based power plant electrical output, emissions, materials usage, and costs for a fully-configurable mix of boiler and steam plant types, feedstocks, and emissions control equipment. The technical documentation and user's guide for the model are included in the download package. PPFM is not engineered to be a consumer-level product and requires knowledge of coal combustion power plants and processes to yield reasonable results.


Co-firing Biomass to Reduce the Environmental Footprint of Coal-fired Heat and Power: A Good Strategy?

Date: 10/2/2013
Contact: Timothy J. Skone, P.E.

The use of biomass as a feedstock for co-fired electricity generation and heat production is attractive because it offers renewable energy derived from a domestically available feedstock and the potential for reductions in greenhouse gases and other environmental impacts. Drivers for the adoption of biomass-based power and heat include the anticipation of forthcoming GHG regulation, compatibility with existing industrial processes and electricity infrastructure, and other potential State or Federal policies. The overarching objective of this work is to gain a better understanding of the potential human health and environmental outcomes associated with the use of biomass in electricity generation and combined heat and power operations. Co-firing biomass with coal reduces GHG emissions but can increase some human health and ecosystem impacts. The type of biomass and the location where it is produced are important, making it difficult to generalize the results in all impact categories.


Power Systems Life Cycle Analysis Tool (Model)

Date: 6/1/2013
Contact: Justin Adder

The Power Systems Life Cycle Analysis Tool (Power LCAT) is a high-level dynamic model that calculates production costs and tracks environmental performance for a range of electricity generation technologies: natural gas combined cycle (NGCC), integrated gasification combined cycle (IGCC), supercritical pulverized coal (SCPC), existing pulverized coal (EXPC), nuclear, and wind (with and without backup power). All of the fossil fuel technologies also include the option of carbon capture and sequestration technologies (CCS). The model allows for quick sensitivity analysis on key technical and financial assumptions, such as: capital, O&M, and fuel costs; interest rates; construction time; heat rates; taxes; depreciation; and capacity factors. Power LCAT is targeted at helping policy makers, students, and interested stakeholders understand the economic and environmental tradeoffs associated with various electricity production options.


Power Systems Life Cycle Analysis Tool Report

Date: 6/1/2013
Contact: Justin Adder

The Power Systems Life Cycle Analysis Tool (Power LCAT) is a high-level dynamic model that calculates production costs and tracks environmental performance for a range of electricity generation technologies: natural gas combined cycle (NGCC), integrated gasification combined cycle (IGCC), supercritical pulverized coal (SCPC), existing pulverized coal (EXPC), nuclear, and wind (with and without backup power). All of the fossil fuel technologies also include the option of carbon capture and sequestration technologies (CCS). The model allows for quick sensitivity analysis on key technical and financial assumptions, such as: capital, O&M, and fuel costs; interest rates; construction time; heat rates; taxes; depreciation; and capacity factors. Power LCAT is targeted at helping policy makers, students, and interested stakeholders understand the economic and environmental tradeoffs associated with various electricity production options.


Life Cycle Analysis: Integrated Gasification Combined Cycle (IGCC) Power Plant Rev. 2

Date: 6/1/2013
Contact: Timothy J. Skone, P.E.

The Life cycle analysis of an integrated gasification combined cycle (IGCC) plant develops an inventory of emissions results and calculates life cycle costs for the plant with and without CCS.


Greenhouse Gas Reductions in the Power Industry Using Domestic Coal and Biomass - Volume 1: IGCC

Date: 2/1/2013
Contact: William Summers

The objective of this study was to simulate biomass co-firing in a dry-fed, entrained-flow gasifier in an integrated gasification combined cycle (IGCC) power plant and examine the resulting performance, environmental response, and economic response. To develop a more complete understanding of the impact of co-feeding biomass, each case was examined using a limited life cycle greenhouse gas (GHG) analysis, which examines GHG emissions beyond the plant stack. Included in the limited life cycle GHG analysis were anthropogenic greenhouse gas emissions from the production, processing, transportation, and fertilization of biomass and from mining, transporting and handling coal.


Greenhouse Gas Reductions in the Power Industry Using Domestic Coal and Biomass - Volume 2: PC Plants

Date: 2/1/2013
Contact: William Summers

The objective of this study was to simulate biomass co-firing in greenfield Pulverized Coal (PC) power plants and examine the resulting performance, environmental response, and economic response. To develop a more complete understanding of the impact of co-feeding biomass, each case was examined using a limited life cycle greenhouse gas (GHG) analysis, which examines GHG emissions beyond the plant stack. Included in the limited life cycle GHG analysis were anthropogenic greenhouse gas emissions from the production, processing, transportation, and fertilization of biomass and from mining, transporting and handling coal.


The Challenge of Co-product Management for Large-scale Energy Systems—Power, Fuel and CO2

Date: 10/2/2012
Contact: Timothy J. Skone, P.E.

Applying traditional co-product management methods such as physical allocation and system expansion in conventional ways can lead to large study uncertainty in LCA of large scale energy systems. The use of advanced power plants with carbon capture as a source of CO2 results in the co-production of electricity and transportation fuels (gasoline or diesel). Co-product allocation can be avoided by expanding the system to include displacement of other routes to electricity generation, but conjecture about the expanded system leads to wide uncertainty. If energy is used as a basis for co-product allocation between electricity and liquid fuel (diesel or gasoline), the differences between the useful energy in the energy products hinders comparability. Partitioning a portion of the system, in this case the power plant, to perform more accurate energy allocation is a third approach, and is possible when detailed plant schematics allow disaggregation of integrated processes.


LCA XII Presentation: Modeling the Uncertainty of Fischer-Tropsch Jet Fuel Life Cycle Inventories with Monte Carlo Simulation

Date: 10/1/2012
Contact: Timothy J. Skone, P.E.

This presentation discusses the use of Monte Carlo simulation to model the uncertainty in a life cycle inventory of the Gasification Systems of coal and biomass. While the inventory is dominated by carbon dioxide emissions from the Adv. Combustion Systems of the fuel, small changes to the feedstocks that are used to make the fuel can make the difference in complying with the Energy Independence and Security Act of 2007.


Exploring Economics and Environmental Performance: Power Systems Life Cycle Analysis Tool (Power LCAT) - LCA XII Presentation

Date: 10/1/2012
Contact: Timothy J. Skone, P.E.

This presentation poster discusses the Power Systems Life Cycle Analysis Tool (Power LCAT). The Power LCAT is a flexible model and associated tool which calculates electricity production costs and tracks life cycle environmental performance for a range of power generation technologies.


LCA XII Presentation: Contribution of Biomass to the LCI of Cofiring Power

Date: 9/26/2012
Contact: Timothy J. Skone, P.E.

Biomass includes agricultural residues, forest thinnings, and dedicated energy crops. Life cycle greenhouse gas (GHG) emission reductions can be accomplished with coal and biomass co-firing only if biomass is produced with high yield rates and there are miniminal changes to land use. Increasing power plant efficiency or using post-combustion carbon dioxide capture and sequestration can lead to larger GHG reductions than co-firing biomass with coal.


Role of Alternative Energy Sources: Pulverized Coal and Biomass Co-firing Technology Assessment (Presentation)

Date: 9/1/2012
Contact: Timothy J. Skone, P.E.

This analysis evaluates the role of coal and biomass co-firing power in the future energy portfolio of the U.S. Coal and biomass co-firing power is evaluated with respect to resource base, growth potential, environmental profile, costs, barriers, risks, and expert opinions. Co-firing is seen as a way of reducing the greenhouse gas emissions of existing coal-fired power plants, but the incorporation of biomass into an existing coal-fired system increases the complexity of feedstock acquisition. Further, the acquisition of biomass has unique GHG burdens that offset, in part, the GHG reductions from the displacement of coal with biomass. Due to the higher feedstock prices of biomass, the co-firing of biomass at a 10 percent share of feedstock energy can increase the cost of electricity by as much as 31 percent. Other risks include regulatory uncertainty; without policies that encourage the use of renewable feedstocks, there is no incentive for producers to invest in co-fired systems.


Role of Alternative Energy Sources: Pulverized Coal and Biomass Co-firing Technology Assessment (Report)

Date: 9/1/2012
Contact: Timothy J. Skone, P.E.

This analysis evaluates the role of coal and biomass co-firing power in the future energy portfolio of the U.S. Coal and biomass co-firing power is evaluated with respect to resource base, growth potential, environmental profile, costs, barriers, risks, and expert opinions. Co-firing is seen as a way of reducing the greenhouse gas emissions of existing coal-fired power plants, but the incorporation of biomass into an existing coal-fired system increases the complexity of feedstock acquisition. Further, the acquisition of biomass has unique GHG burdens that offset, in part, the GHG reductions from the displacement of coal with biomass. Due to the higher feedstock prices of biomass, the co-firing of biomass at a 10 percent share of feedstock energy can increase the cost of electricity by as much as 31 percent. Other risks include regulatory uncertainty; without policies that encourage the use of renewable feedstocks, there is no incentive for producers to invest in co-fired systems.


Role of Alternative Energy Sources: Pulverized Coal and Biomass Co-firing Technology Assessment (Fact Sheet)

Date: 8/30/2012
Contact: Timothy J. Skone, P.E.

This analysis evaluates the role of coal and biomass co-firing power in the future energy portfolio of the U.S. Coal and biomass co-firing power is evaluated with respect to resource base, growth potential, environmental profile, costs, barriers, risks, and expert opinions. Co-firing is seen as a way of reducing the greenhouse gas emissions of existing coal-fired power plants, but the incorporation of biomass into an existing coal-fired system increases the complexity of feedstock acquisition. Further, the acquisition of biomass has unique GHG burdens that offset, in part, the GHG reductions from the displacement of coal with biomass. Due to the higher feedstock prices of biomass, the co-firing of biomass at a 10 percent share of feedstock energy can increase the cost of electricity by as much as 31 percent. Other risks include regulatory uncertainty; without policies that encourage the use of renewable feedstocks, there is no incentive for producers to invest in co-fired systems.


Power Systems Life Cycle Analysis Tool (Power LCAT) Technical Guide

Date: 5/1/2012
Contact: Justin Adder

Power LCAT is a high-level dynamic model that calculates production costs and tracks environmental performance for a range of electricity generation technologies. This report summarizes key assumptions and results for version 2.0 of Power LCAT. This report has three goals: to explain the basic methodology used to calculate production costs and to estimate environmental performance; to provide a general overview of the model operation and initial results; and to demonstrate the wide range of options for conducting sensitivity analysis.


Life Cycle Assessment of Natural Gas Extraction, Delivery and Electricity Production - NAS/TRB Conference Presentation

Date: 1/1/2012
Contact: Timothy J. Skone, P.E.

This presentation was given at the National Academy of Sciences, 91st Annual Transportation Research Board Meeting in Washington, D.C. on January 25. NETL reports natural gas fired power production GHG emissions to be 53% lower than average base load coal fired power production. The presentation provides an overview of NETL's greenhouse gas results for various types of natural gas, including Marcellus Shale, and compares the results for natural gas fired power production to coal fired power production. The presentation focused on understanding the variability and uncertainty in recent natural gas GHG estimates.


Life Cycle Greenhouse Gas Analysis of Advanced Jet Propulsion Fuels: F-T Based SPK-1 Case Study (Report)

Date: 12/1/2011
Contact: Timothy J. Skone, P.E.

In response to the Energy Independence and Security Act (EISA), NETL conducted an LCA (LCA) of 10 fuel production pathways using Fischer-Tropsch synthesis. These pathways use varying combinations of coal and swithgrass feedstocks and two options for carbon management (sequestration or enhanced oil recovery). Only greenhouse gas (GHG) emissions are inventoried. Comparative analysis of the results demonstrate that higher percentages of biomass result in lower life cycle GHG emissions when using switchgrass. The choice of carbon management strategy has an effect on the results.


Estimating Freshwater Needs to Meet Future Thermoelectric Generation Requirements - 2011 Update

Date: 10/1/2011
Contact: Erik Shuster

Future freshwater withdrawal and consumption from domestic thermoelectric generation sources were estimated for five cases, using EIA AEO 2011 regional projections for capacity additions and retirements.


Life Cycle Greenhouse Gas Analysis of Advanced Jet Propulsion Fuels: Fischer Tropsch Based SPK-1 Case Study (Model)

Date: 9/1/2011
Contact: Timothy J. Skone, P.E.

In response to the Energy Independence and Security Act (EISA), NETL conducted an LCA of 10 fuel production pathways using Fischer-Tropsch synthesis. These pathways use varying combinations of coal and swithgrass feedstocks and two options for carbon management (sequestration or enhanced oil recovery). Only greenhouse gas (GHG) emissions are inventoried. Comparative analysis of the results demonstrate that higher percentages of biomass result in lower life cycle GHG emissions when using switchgrass. The choice of carbon management strategy has an effect on the results.


Life Cycle Greenhouse Gas Analysis of Advanced Jet Propulsion Fuels: F-T Based SPK-1 Case Study (Presentation)

Date: 9/1/2011
Contact: Timothy J. Skone, P.E.

The purpose of this report is to provide a framework and guidance for estimating the life cycle greenhouse gas emissions for transportation fuels, specifically aviation fuels derived from coal and biomass. This report is a detailed case study of ten coal and biomass to SPK-1 aviation fuel scenarios. The case study follows the framework and guidance document developed by the Interagency Work Group for Alternative Fuels (IAWG-AF) published in 2010. The report is a product of the workgroup members, was sponsored by the U.S. Air Force and the project was led by the National Energy Technology Laboratory. The results of this case study are a detailed report and model documenting the methodology, data, and conclusions. A summary presentation is also included with the report and model.


CBTL Jet Fuel Model

Date: 2/16/2011
Contact: Timothy J. Skone, P.E.

The Connecticut Center for Advanced Technology (CCAT) has received funding from the Defense Logistics Agency (DLA) Energy to demonstrate how liquid fuel can be produced from coal and meet the Energy Independence and Security Act (EISA) of 2007 greenhouse gas (GHG) requirement for DOD fuel purchases of synthetic fuel. Section 526 of EISA requires that any fuel purchases have a life-cycle CO2 emission less than conventional petroleum fuel. This model evaluates different scenarios for the conversion of coal and biomass to jet fuel using oxygen blown, transport reactor integrated gasifier and Fischer-Tropsch catalyst configurations.


Life Cycle Analysis: Integrated Gasification Combined Cycle (IGCC) Power Plant (zip file)

Date: 9/30/2010
Contact: Robert James

Life Cycle Analysis of an Integrated Gasification Combined Cycle plant. Develops an inventory of emissions results, and calculates Life Cycle costs for the plant with and without CCS.