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Single-Crystal Sapphire Optical Fiber Sensor Instrumentation

This report summarizes technical progress on the program “Single-Crystal Sapphire Optical Fiber Sensor Instrumentation,” funded by the National Energy Technology Laboratory of the U.S. Department of Energy, and performed by the Center for Photonics Technology of the Bradley Department of Electrical and Computer Engineering at Virginia Tech. This project was completed in three phases, each with a separate focus. Phase I of the program, from October 1999 to April 2002, was devoted to development of sensing schema for use in high temperature, harsh environments. Different sensing designs were proposed and tested in the laboratory. Phase II of the program, from April 2002 to April 2009, focused on bringing the sensor technologies, which had already been successfully demonstrated in the laboratory, to a level where the sensors could be deployed in harsh industrial environments and eventually become commercially viable through a series of field tests. Also, a new sensing scheme was developed and tested with numerous advantages over all previous ones in Phase II. Phase III of the program, September 2009 to December 2013, focused on development of the new sensing scheme for field testing in conjunction with materials engineering of the improved sensor packaging lifetimes. In Phase I, three different sensing principles were studied: sapphire air-gap extrinsic Fabry-Perot sensors; intensity-based polarimetric sensors; and broadband polarimetric sensors. Black body radiation tests and corrosion tests were also performed in this phase. The outcome of the first phase of this program was the selection of broadband polarimetric differential interferometry (BPDI) for further prototype instrumentation development. This approach is based on the measurement of the optical path difference (OPD) between two orthogonally polarized light beams in a single-crystal sapphire disk. At the beginning of Phase II, in June 2004, the BPDI sensor was tested at the Wabash River coal gasifier facility in Terre Haute, Indiana. Due to business conditions at industrial partner and several logistical problems, this field test was not successful. An alternative high-temperature sensing system using sapphire wafer-based extrinsic Fabry-Perot interferometry was then developed as a significant improvement over the BPDI solution. From June 2006 to June 2008, three consecutive field tests were performed with the new sapphire wafer sensors at the TECO coal gasifier in Tampa, Florida. One of the sensors survived in the industrial coal gasifier for 7 months, over which time the existing thermocouples were replaced twice. The outcome of these TECO field tests suggests that the sapphire wafer sensor has very good potential to be commercialized. However packaging and sensor protection issues need additional development. During Phase III, several major improvements in the design and fabrication process of the sensor have been achieved through experiments and theoretical analysis. Studies on the property of the key components in the sensor head, including the sapphire fiber and sapphire wafer, were also conducted, for a better understanding of the sensor behavior. A final design based on all knowledge and experience has been developed, free of any issues encountered during the entire research. Sensors with this design performed well as expected in lab long-term tests, and were deployed in the sensing probe of the final coal-gasifier field test. Sensor packaging and protection was improved through materials engineering through testing of packaging designs in two blank probe packaging tests at Eastman Chemical in Kingsport, TN. Performance analysis of the blank probe packaging resulted in improve package designs culminating in a 3rd generation probe packaging utilized for the full field test of the sapphire optical sensor and materials designed sensor packaging.

47 OTHER INSTRUMENTATION↗

Laurentian Bioenergy Project

Work performed under this contract involves development of forest management guidelines related to removal of forest harvest residues from forested sites and brushlands in Minnesota, assessments of biomass availability from forests and brushlands and logistics and equipment associated with handling woody biomass with emphasis on evaluation of a trailer-mounted bundling system. Also, work on hybrid poplar breeding, field testing and yield analysis is included. Evaluation of the production of aspen and red pine along with opportunities to procure woody biomass through thinning operations in red pine is described. Finally, an assessment of issues related to increasing biomass usage at the Laurentian Energy Authority generation facilities is discussed.

09 BIOMASS FUELS↗

NSUF Irradiated Materials Library

The Nuclear Science User Facilities has been in the process of establishing an innovative Irradiated Materials Library concept for maximizing the value of previous and on-going materials and nuclear fuels irradiation test campaigns, including utilization of real-world components retrieved from current and decommissioned reactors. When the ATR national scientific user facility was established in 2007 one of the goals of the program was to establish a library of irradiated samples for users to access and conduct research through competitively reviewed proposal process. As part of the initial effort, staff at the user facility identified legacy materials from previous programs that are still being stored in laboratories and hot-cell facilities at the INL. In addition other materials of interest were identified that are being stored outside the INL that the current owners have volunteered to enter into the library. Finally, over the course of the last several years, the ATR NSUF has irradiated more than 3500 specimens as part of NSUF competitively awarded research projects. The Logistics of managing this large inventory of highly radioactive poses unique challenges. This document will describe materials in the library, outline the policy for accessing these materials and put forth a strategy for making new additions to the library as well as establishing guidelines for minimum pedigree needed to be included in the library to limit the amount of material stored indefinitely without identified value.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Continuation and Enhancement of the MPOWIR Program

MPOWIR is a community-based program that provides mentoring to physical oceanographers from late graduate school through early careers. The overall goal of MPOWIR is to make mentoring opportunities for junior physical oceanographers universally available and of higher quality by expanding the reach of mentoring opportunities beyond individual home institutions. The aim is to reduce the barriers to career development for all junior scientists in the field, with a particular focus on improving the retention of junior women. Over the past five years MPOWIR has expanded significantly. This funding cycle saw the development and enhancement of MPOWIR’s programs and outreach opportunities. MPOWIR’s main programmatic offerings are: mentor groups, a biannual conference, a website and blog, and town hall meetings at national events. Since 2009, MPOWIR has hosted 15 mentor groups, three Pattullo conferences, and created a website that has attracted over 50,000 visitors. MPOWIR’s mentoring groups and Pattullo conferences have reached more than 130 unique participants. Mentor Groups Mentor groups were established in the fall of 2008, and continue to gain momentum after 5 years. Since 2009, 11 groups have formed, with participants mainly, but not exclusively, drawn from Pattullo attendees. To gauge the impact of mentor groups, participants are surveyed approximately annually. Based on an extensive 2011 survey, 100% of mentoring group participants reported that they made progress on their stated scientific, professional, and personal goals. As part of these surveys, participants are asked what they value about their mentoring group, what the benefit of the mentoring group is to their current position, and they are asked questions about the logistics and setup of the groups. Based on the survey conducted in 2012, all participants rated participation in these groups a valuable experience, with particular value placed on feedback on professional development (100% Excellent to Good) and feedback on personal matters (92% Excellent to Good). Pattullo Conferences The centerpiece of the MPOWIR program is the Pattullo Conference, named for June Pattullo, the first woman to receive a Ph.D. in physical oceanography. At each event, the agenda includes research talks, professional development sessions, small group activities, and a question-and-answer session about early-career and retention issues posed by junior scientists to senior researchers. Pattullo Conference participants are surveyed after each conference about their experience. This survey asks participants to rate their opinion on specific topics and invites comments. Combining results from three conferences, 99% of junior participants would recommend the conference to another junior scientist. Of the junior participants, 92% rated the conference as “extremely valuable” overall, with a particular value placed on networking and professional development opportunities. Overall Impact To gain a better perspective on the success of MPOWIR to date, early participants were surveyed in 2013 about their current position, and the impact of MPOWIR on their career path. Individuals were asked to rank the extent to which MPOWIR had impacted various aspects of their professional growth. These aspects included efforts to obtain their current position; exposure to professional development skills; broadening of their professional network; mentoring on work and family balance; performance in current position; and raising awareness of mentoring in career development. Participants overwhelming indicated that MPOWIR had positively impacted all of these aspects. In particular, 95% of respondents expressed that MPOWIR exposed them to useful professional development skills “to a great extent” and 89% consider MPOWIR to have positively impacted their professional network “to a great extent”. Of those surveyed, the majority of participants were 2 years from their Ph.D. at the time of initial involvement. Their current job positions are well distributed over all post-Ph.D. categories: the greatest percentages of positions held are at research institutions (non-academic) or government agencies (29.3%), followed closely by non-faculty research positions at universities (27.6%) and faculty at research universities (22.4%). The remaining positions held (4-year college faculty, profit or not-for-profit company, policy, and graduate students) collectively total 19%. These initial indications point toward mentoring, as offered by MPOWIR, as an effective means for improving retention of women in physical oceanography.

58 GEOSCIENCES↗

DNA Everywhere. A Guide for Simplified Environmental Genomic DNA Extraction Suitable for Use in Remote Areas

Collecting field samples from remote or geographically distant areas can be a financially and logistically challenging. With participation of a local organization where the samples are originated from, gDNA samples can be extracted from the field and shipped to a research institution for further processing and analysis. The ability to set up gDNA extraction capabilities in the field can drastically reduce cost and time when running long-term microbial studies with a large sample set. The method outlined here has developed a compact and affordable method for setting up a “laboratory” and extracting and shipping gDNA samples from anywhere in the world. This white paper explains the process of setting up the “laboratory”, choosing and training individuals with no prior scientific experience how to perform gDNA extractions and safe methods for shipping extracts to any research institution. All methods have been validated by the Andersen group at Lawrence Berkeley National Laboratory using the Berkeley Lab PhyloChip.

59 BASIC BIOLOGICAL SCIENCES↗

Supply Chain Sustainability Analysis of Fast Pyrolysis and Hydrotreating Bio-Oil to Produce Hydrocarbon Fuels

The Department of Energy’s (DOE) Bioenergy Technology Office (BETO) aims at developing and deploying technologies to transform renewable biomass resources into commercially viable, high-performance biofuels, bioproducts and biopower through public and private partnerships (DOE, 2015). BETO and its national laboratory teams conduct in-depth techno-economic assessments (TEA) of technologies to produce biofuels. These assessments evaluate feedstock production, logistics of transporting the feedstock, and conversion of the feedstock to biofuel. There are two general types of TEAs. A design case is a TEA that outlines a target case for a particular biofuel pathway. It enables identification of data gaps and research and development needs, and provides goals and targets against which technology progress is assessed. On the other hand, a state of technology (SOT) analysis assesses progress within and across relevant technology areas based on actual experimental results relative to technical targets and cost goals from design cases, and includes technical, economic, and environmental criteria as available.

09 BIOMASS FUELS↗

Final Technical Report: Using Solid Particles as Heat Transfer Fluid for use in Concentrating Solar Power (CSP) Plants

In today’s industrial economy, energy consumption has never been higher. Over the last 15 years the US alone has consumed an average of nearly 100 quadrillion BTUs per year [21]. A need for clean and renewable energy sources has become quite apparent. The SunShot Initiative is an ambitious effort taken on by the United States Department of Energy that targets the development of solar energy that is cost-competitive with other methods for generating electricity. Specifically, this work is concerned with the development of concentrating solar power plants (CSPs) with granular media as the heat transfer fluid (HTF) from the solar receiver. Unfortunately, the prediction of heat transfer in multiphase flows is not well understood. For this reason, our aim is to fundamentally advance the understanding of multiphase heat transfer, particularly in gas-solid flows, while providing quantitative input for the design of a near black body receiver (NBB) that uses solid grains (like sand) as the HTF. Over the course of this three-year project, a wide variety of contributions have been made to advance the state-of-the art description for non-radiative heat transfer in dense, gas-solid systems. Comparisons between a state-of-the-art continuum heat transfer model and discrete element method (DEM) simulations have been drawn. The results of these comparisons brought to light the limitations of the continuum model due to inherent assumptions in its derivation. A new continuum model was then developed for heat transfer at a solid boundary by rigorously accounting for the most dominant non-radiative heat transfer mechanism (particle-fluid-wall conduction). The new model is shown to be in excellent agreement with DEM data and captures the dependence of heat transfer on particle size, a dependency that previous continuum models were not capable of. DEM and the new continuum model were then employed to model heat transfer in a variety of receiver geometries. The results provided crucial feedback on the efficiency and feasibility of various designs. Namely, a prototype design consisting of an array of heated hexagonal tubes was later supplanted by a vertical conduit with internal baffles. Due to low solids heat transfer on the bottom faces of the hexagonal tubes in the prototype, the predicted wall temperature gradients exceeded the design limitations. By contrast, the vertical conduit can be constructed to continually force particle-wall contacts, and thus, result in more desirable solids heat transfer and wall temperature gradients. Finally, a new heat flux boundary condition was developed for DEM simulations to assess the aforementioned wall temperature gradients. The new boundary condition advances current state-of-the-art techniques by allowing the heat fluxes to each phase to vary with space and time while the total flux remains constant. Simulations with the new boundary condition show that the total boundary heat flux is in good agreement with the imposed total boundary heat flux. While the methods we have utilized here are primarily numerical and fundamental by nature, they offer some key advantages of: (i) being robust and valid over a large range of conditions, (ii) able to quickly explore large parameter spaces, and (iii) aid in the construction of experiments. We have ultimately leveraged our computational capabilities to provide feedback on the design of a CSP which possesses great potential to become a cost effective source of clean and renewable electricity. Overall, ensuring that future energy demands are met in a responsible and efficient manner has far reaching impacts that span both ecologic and economic concerns. Regarding logistics, the project was successfully re-negotiated after the go/no-decisions of Years 1 and 2. All milestones were successfully completed.

14 SOLAR ENERGY↗

Laser Ceilometer CL51 Demonstration Field Campaign Report

Improvements in the measurements of clouds and the ability to support observation systems are critically important to advancing our understanding and improving global climate model performance. The purpose of a demonstration of the Vaisala CL51 ceilometer was to evaluate its high-range capabilities as a possible augmentation to data provided by the CL31 ceilometer that currently is deployed at U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility sites. Vaisala performed a no-cost demonstration of the equipment; Pacific Northwest National Laboratory (PNNL) supported the data analysis; and ARM provided logistical support, power, maintenance, etc. The laser ceilometer provided measurements of cloud-base height, vertical visibility, and backscatter profile at a vertical range of 15 km. The ceilometer demonstration was conducted during the Characterization of Cirrus and Aerosol Properties campaign (CCAP) to provide coincident observations of cirrus cloud heights and potential backscatter signals by aerosols. This campaign included deployment of a CL51 ceilometer at the ARM Facility’s Southern Great Plains (SGP) site, co-located with the current CL31, micropulse lidar, and balloon-borne sounding system. Data collected from these sensors were analyzed to compare and contrast the data from the CL51 ceilometer.

54 ENVIRONMENTAL SCIENCES↗

Simplified Processing Method for Meter Data Analysis

Simple/Quick metered data processing method that can be used for Army Metered Data Management System (MDMS) and Logistics Innovation Agency data, but may also be useful for other large data sets. Intended for large data sets when analyst has little information about the buildings.

97 MATHEMATICS AND COMPUTING↗

Renewable Enhanced Feedstocks for Advanced Biofuels and Bioproducts (REFABB)

The basic concept of the REFABB project was that by genetically engineering the biomass crop switchgrass to produce a natural polymer PHB, which is readily broken down by heating (thermolysis) into the chemical building block crotonic acid, sufficient additional economic value would be added for the grower and processor to make it an attractive business at small scale. Processes for using thermolysis to upgrade biomass to densified pellets (char) or bio-oil are well known and require low capital investment similar to a corn ethanol facility. Several smaller thermolysis plants would then supply the densified biomass, which is easier to handle and transport to a centralized biorefinery where it would be used as the feedstock. Crotonic acid is not by itself a large volume commodity chemical, however, the project demonstrated that it can be used as a feedstock to produce a number of large volume chemicals including butanol which itself is a biofuel target. In effect the project would try to address three key technology barriers, feedstock logistics, feedstock supply and cost effective biomass conversion. This project adds to our understanding of the potential for future biomass biorefineries in two main areas. The first addressed in Task A was the importance and potential of developing an advanced value added biomass feedstock crop. In this Task several novel genetic engineering technologies were demonstrated for the first time. One important outcome was the identification of three novel genes which when re-introduced into the switchgrass plants had a remarkable impact on increasing the biomass yield based on dramatically increasing photosynthesis. These genes also turned out to be critical to increasing the levels of PHB in switchgrass by enabling the plants to fix carbon fast enough to support both plant growth and higher levels of the polymer. Challenges in the critical objective of Task B, demonstrating conversion of the PHB in biomass to crotonic acid at over 90% yield, demonstrated the need to consider up-front the limitations of trying to adopt existing equipment to a task for which subsequent basic research studies indicated it was not suitable. New information was developed in the most complex of the chemical conversions studied, advanced catalysis to make acrylic acid, a chemical used widely to make paints, and this was published in a scientific journal. In regard to the technical effectiveness, the crop science aspects were for the most part remarkably effective in addressing the underlying objectives indicating the soundness of the technical approach. With time, it should be possible to fully develop the advanced biomass biorefinery feedstock. Challenges within the thermolysis step to recover crotonic acid meant that by the end of the project we were not able to demonstrate an economic case based on data from scaled up equipment. Solving this will take further research and development work. As a general statement, the broadest public good is in demonstrating the value of funding a very unique approach to the complex problem of enabling large-scale biomass biorefineries which resulted in significant progress towards the ultimate goal and a clearer understanding of the technical hurdles remaining. Perhaps not surprisingly, some of the broader benefits to the public come from the use of the REFABB project innovations in areas unrelated to the initial objective. It is worth highlighting the breakthrough developments in identifying three single global regulator genes which can be engineered into plants to dramatically increase photosynthesis and carbon capturing ability. These genes have tremendous potential for use in major food crops, in particular corn to enhance grain yield and based on recent findings, increase the root density, a critical key to increasing carbon sequestration in agriculture and improving the sustainability of global food and biofuel production.

09 BIOMASS FUELS↗

2016 Billion-Ton Report: Advancing Domestic Resources for a Thriving Bioeconomy

This product builds on previous efforts, namely the 2005 Billion-Ton Study (BTS) and the 2011 U.S. Billion-Ton Update (BT2).With each report, greater perspective is gained on the potential of biomass resources to contribute to a national energy strategy. Similarly, each successive report introduces new questions regarding commercialization challenges. BTS quantified the broad biophysical potential of biomass nationally, and BT2 elucidated the potential economic availability of these resources. These reports clearly established the potential availability of up to one billion tons of biomass resources nationally. However, many questions remain, including but not limited to crop yields, climate change impacts, logistical operations, and systems integration across production, harvest, and conversion. The present report aims to address many of these questions through empirically modeled energy crop yields, scenario analysis of resources delivered to biorefineries, and the addition of new feedstocks. Volume 2 of the 2016 Billion-Ton Report is expected to be released by the end of 2016. It seeks to evaluate environmental sustainability indicators of select scenarios from volume 1 and potential climate change impacts on future supplies.

09 BIOMASS FUELS↗

Technical and Economic Assessment of Solar Photovoltaic for Groundwater Extraction on the Hanford Site

The overall goal of environmental remediation is to protect human health and the environment. Implementing renewable energy sources such as solar photovoltaic (PV) in groundwater extraction and pump-and-treat (P&T) systems may help minimize the environmental footprint of remediation efforts. The first step in considering solar PV for powering Hanford groundwater extraction is assessing the technical and economic feasibility and identifying potential target locations where implementation would be most successful. Accordingly, a techno-economic assessment of solar PV for Hanford groundwater extraction was completed in FY15. Multiple solar PV alternatives ranging in size from 1.2 to 22.4 kWp DC were evaluated and compared against traditional grid-powered systems. Results indicate that the degree to which solar PV alternatives are feasible is primarily a function of the distance of avoided power cable costs and the inclusion of an energy storage component. Standalone solar PV systems provide an energy source at the well and avoid the costs and logistics associated with running long lengths of expensive power cable to the well-head. When solar PV systems include a battery storage component, groundwater can be pumped continuously day and night in a year-round schedule. However, due to the high cost premium of the energy storage component, a fully solar-powered solution could not provide an economic direct replacement for line-powered pumping systems. As a result, the most ideal target locations for successful implementation of solar PV on the Hanford Site are remote or distant extraction wells where the primary remedial objective is contaminant mass removal (as opposed to hydraulic containment) and three-season (March through October) intermittent pumping is acceptable (e.g. remediation of hexavalent chromium in 200-UP-1).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Carbon Fiber from Biomass

Carbon fiber (CF), known also as graphite fiber, is a lightweight, strong, and flexible material used in both structural (load-bearing) and non-structural applications (e.g., thermal insulation). The high cost of precursors (the starting material used to make CF, which comes predominately from fossil sources) and manufacturing have kept CF a niche market with applications limited mostly to high-performance structural materials (e.g., aerospace). Alternative precursors to reduce CF cost and dependence on fossil sources have been investigated over the years, including biomass-derived precursors such as rayon, lignin, glycerol, and lignocellulosic sugars. The purpose of this study is to provide a comprehensive overview of CF precursors from biomass and their market potential. We examine the potential CF production from these precursors, the state of technology and applications, and the production cost (when data are available). We discuss their advantages and limitations. We also discuss the physical properties of biomass-based CF, and we compare them to those of polyacrylonitrile (PAN)-based CF. We also discuss manufacturing and end-product considerations for bio-based CF, as well as considerations for plant siting and biomass feedstock logistics, feedstock competition, and risk mitigation strategies. The main contribution of this study is that it provides detailed technical and market information about each bio-based CF precursor in one document while other studies focus on one precursor at a time or a particular topic (e.g., processing). Thus, this publication allows for a comprehensive view of the CF potential from all biomass sources and serves as a reference for both novice and experienced professionals interested in CF production from alternative sources.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Transportation of Large Wind Components: A Permitting and Regulatory Review

This report summarizes permitting and regulatory issues associated with transporting wind turbine blades, towers, and nacelles as well as large transformers (wind components). These wind components are commonly categorized as oversized and overweight (OSOW) and require specific permit approvals from state and local jurisdictions. The report was developed based on a Quadrennial Energy Review (QER) recommendation on logistical requirements for the transportation of 'oversized or high-consequence energy materials, equipment, and components.'

17 WIND ENERGY↗

Optimization of Installation, Operation and Maintenance at Offshore Wind Projects in the U.S.: Review and Modeling of Existing and Emerging Approaches

The United States Department of Energy (DOE) awarded a grant to GL Garrad Hassan (GL GH) to investigate the logistics, opportunities, and costs associated with existing and emerging installation and operation and maintenance (O&M) activities at offshore wind projects as part of the DOE’s program to reduce barriers facing offshore wind project development in the United States (U.S.). This report (the Report) forms part of Subtopic 5.3 “Optimized Installation, Operation and Maintenance Strategies Study” which in turn is part of the “Removing Market Barriers in U.S. Offshore Wind” set of projects for the DOE. The purpose of Subtopic 5.3 is to aid and facilitate informed decision-making regarding installation and O&M during the development, installation, and operation of offshore wind projects in order to increase efficiency and reduce the levelized cost of energy (LCoE). Given the large area of U.S. territorial waters, the generally higher mean wind speeds offshore, and the proximity to the coast of many large U.S. cities, offshore wind power has the potential to become a significant contributor of energy to U.S. markets. However, for the U.S. to ensure that the development of offshore wind energy projects is carried out in an efficient and cost-effective manner, it is important to be cognizant of the current and emerging practices in both the domestic and international offshore wind energy industries. The U.S. can harness the experience gained globally and combine this with the skills and assets of an already sizeable onshore wind industry, as well as the resources of a mature offshore oil and gas industry, to develop a strong offshore wind sector. The work detailed in this report is aimed at assisting with that learning curve, particularly in terms of offshore specific installation and O&M activities. This Report and the Installation and O&M LCoE Analysis Tool, which were developed together by GL GH as part of this study, allow readers to identify, model and probe the economic merits and sensitivities of various approaches to construction and O&M practices, using illustrative offshore projects across a wide range of alternative offshore development areas located in U.S. waters. The intention is to assist decision-makers in clearly understanding the relative economic benefits of both conventional and novel construction installation methodologies and maintenance techniques within the critical parameters of a Project’s LCoE.

17 WIND ENERGY↗

Planning and Execution of a Marine Methane Hydrate Pressure Coring Program for the Walker Ridge and Green Canyon Areas of the Gulf of Mexico

The objective of this project (and report) is to produce a guide to developing scientific, operational, and logistical plans for a future methane hydrate-focused offshore pressure coring program. This report focuses primarily on a potential coring program in the Walker Ridge 313 and Green Canyon 955 blocks where previous investigations were undertaken as part of the 2009 Department of Energy JIP Leg II expedition, however, the approach to designing a pressure coring program that was utilized for this project may also serve as a useful model for planning pressure coring programs for hydrates in other areas. The initial portion of the report provides a brief overview of prior investigations related to gas hydrates in general and at the Walker Ridge 313 and Green Canyon 955 blocks in particular. The main content of the report provides guidance for various criteria that will come into play when designing a pressure coring program.

54 ENVIRONMENTAL SCIENCES↗

Transportation Energy Futures Series: Freight Transportation Demand: Energy-Efficient Scenarios for a Low-Carbon Future

Freight transportation demand is projected to grow to 27.5 billion tons in 2040, and by extrapolation, to nearly 30.2 billion tons in 2050, requiring ever-greater amounts of energy. This report describes the current and future demand for freight transportation in terms of tons and ton-miles of commodities moved by truck, rail, water, pipeline, and air freight carriers. It outlines the economic, logistics, transportation, and policy and regulatory factors that shape freight demand; the possible trends and 2050 outlook for these factors, and their anticipated effect on freight demand and related energy use. After describing federal policy actions that could influence freight demand, the report then summarizes the available analytical models for forecasting freight demand, and identifies possible areas for future action.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Multiple Lines of Evidence

This paper discusses the process of identifying factors that influence the contamination level of a given decision area and then determining the likelihood that the area remains unacceptable. This process is referred to as lines of evidence. These lines of evidence then serve as inputs for the stratified compliance sampling (SCS) method, which requires a decision area to be divided into strata based upon contamination expectations. This is done in order to focus sampling efforts more within stratum where contamination is more likely and to use the domain knowledge about these likelihoods of the stratum remaining unacceptable to buy down the number of samples necessary, if possible. Two different building scenarios were considered as an example (see Table 3.1). SME expertise was elicited concerning four lines of evidence factors (see Table 3.2): 1) amount of contamination that was seen before decontamination, 2) post-decontamination air sampling information, 3) the applied decontaminant information, and 4) the surface material. Statistical experimental design and logistic regression modelling were used to help determine the likelihood that example stratum remained unacceptable for a given example scenario. The number of samples necessary for clearance was calculated by applying the SCS method to the example scenario, using the estimated likelihood of each stratum remaining unacceptable as was determined using the lines of evidence approach. The commonly used simple random sampling (SRS) method was also used to calculate the number of samples necessary for clearance for comparison purposes. The lines of evidence with SCS approach resulted in a 19% to 43% reduction in total number of samples necessary for clearance (see Table 3.6). The reduction depended upon the building scenario, as well as the level of percent clean criteria. A sensitivity analysis was also performed showing how changing the estimated likelihoods of stratum remaining unacceptable affect the number of samples necessary. In conclusion, using the lines of evidence approach with the SCS method can reduce sample sizes when SME are able to identify factors that reduce the likelihood that an area remain unacceptable.

97 MATHEMATICS AND COMPUTING↗