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DOE OSTI2021

Transportation Energy Data Book: Edition 39

The Transportation Energy Data Book: Edition 39 is a statistical compendium prepared and published by Oak Ridge National Laboratory (ORNL) under contract with the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office. Designed for use as a desk-top reference, the Data Book represents an assembly and display of statistics and information that characterize transportation activity and presents data on other factors that influence transportation energy use. The purpose of this document is to present relevant statistical data in the form of tables and graphs. The latest edition of the Data Book is available via the Internet (tedb.ornl.gov).This edition of the Data Book has 13 chapters which focus on various aspects of the transportation industry. Chapter 1 focuses on petroleum; Chapter 2 – energy; Chapter 3 – highway vehicles; Chapter 4 – light vehicles; Chapter 5 – heavy vehicles; Chapter 6 – alternative fuel vehicles; Chapter 7 – transit and other shared mobility; Chapter 8 – fleet vehicles; Chapter 9 – household vehicles; Chapter 10 – nonhighway modes; Chapter 11 – transportation and the economy; Chapter 12 – greenhouse gas emissions; and Chapter 13 – criteria pollutant emissions. The sources used represent the latest available data. There are also three appendices which include detailed source information for some tables, measures of conversion, and energy tables with electricity generation and distribution. A glossary of terms is also included for the reader’s convenience.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2021

2020 Cost Analysis of Hydropower Options at Non-Powered Dams

This report provides a cost analysis of potential hydropower development for representative non-powered dam (NPD) sites in the United States. The overarching objective is to support the establishment of a basis for evaluating progress towards improving the competitiveness of new hydropower development for electricity generation. The representative sites, herein referred to as “reference sites”, were selected from sites with detailed water resource data to support the cost analysis. Facility designs, capital costs, plant generation and efficiency profiles, capacity factors, and levelized costs of energy (LCOE) are presented for the sites under baseline and near-term innovation cases. The baseline case represents facility configurations using technologies that are already widely applied in the hydropower industry, whereas near-term innovations are technologies likely to reach wide acceptance within the next 5 to 10 years. Cost savings in the near-term relative to the baseline are discussed to illustrate the potential benefits to the hydropower industry from research and development (R&D) and adoption of these innovations. Medium- to long-term innovation options expected from ongoing private and government R&D efforts are also highlighted but are not quantified in this report because of a current lack of complete information on these options. The key findings of the cost analysis in this study imply that near-term innovations could reduce the baseline costs of hydropower development at US NPD sites. Thus, if remaining R&D issues with these near-term innovations can be resolved within the next 5 to 10 years, industry-wide adoption of these technologies and improved competitiveness of NPD hydropower development can be expected. Specific key findings of the analysis include the following: 1) Potential installed capacity at the NPD sites evaluated in this study vary from 200 kW to 70 MW, representing two orders of magnitude variation across nearly 20 sites; 2) Capital costs, not including development costs, for the sites evaluated in this study vary from $2,200/kW to $34,000/kW but are below $12,000/kW for most sites; 3) Baseline LCOE estimates for lake dams are from $79/MWh to $790/MWh with most sites under $400/MWh, whereas estimates for lock dams are from $134/MWh to $289/MWh with most sites under $200/MWh; 4) Reductions in capital cost per kilowatt under the near-term innovation case are from −77% to −14% for lake dams and −21% to −2.1% for lock dams (excluding one site with a 14% increase in per-kilowatt capital costs); 5) Combined changes in capital costs and capacity factors in the near-term case relative to the baseline lead to reductions in LCOE of −71% to −14% for lake dams and −21% to −14% for lock dams; 6) Overall, LCOE reductions lead to 8 of the 18 sites under the near-term case having LCOE values below $150/MWh compared with only 2 of 18 sites in the baseline case.

13 HYDRO ENERGY↗

DOE OSTI2021

Development of Gyrosole™ and Solar Thermal HVAC Technology for 20-60kW Applications, Final Report, CRADA No. TC02164.0

This was a collaborative effort between Lawrence Livermore National Security, LLC as manager and operator of Lawrence Livermore National Laboratory (LLNL) and Sol Xorce LLC to develop LLNL’s Gyrosole™ solar thermal energy system. The original scope of the CRADA project was to develop LLNL’s Gyrosole™thermal-powered motor technology for solar thermal energy system use, and was originally entitled, "Development of Gyrosole™ Solar Thermal Technology for 20-60 kW Applications". The scope and title of the project were later modified under Amendment One to the CRADA. The technical objective of this CRADA project was to develop Gyrosole™ motor technology so that it is marketplace-ready, and to produce a motor prototype that: Produces 50kW power at >22% efficiency; Operates oil-free; Has sufficient reliability and lifetime to be suitable for both commercial and residential applications; Costs less than $100 per kW installed to produce at scale; and, Can be combined cost-effectively to produce 200kW. The motor prototype would be integrated into model systems that provide electricity generation in combination with air/water heating, heat-pump driven cooling, desiccant dehumidification, and light industrial heat supply.

14 SOLAR ENERGY↗

DOE OSTI2021

Halfway to Zero: Progress towards a Carbon-Free Power Sector

Sharply reducing carbon emissions is imperative to prevent the worst effects of climate change. Yet even in the power sector—often viewed as the lynchpin to economy-wide decarbonization, and where low-carbon solutions are increasingly plentiful and cost-effective—the pace and scale of the required transformation can be daunting. A review of historical trends, however, shows the progress the power sector has already made in reducing emissions. Fifteen years ago, many business-as-usual projections anticipated that annual carbon dioxide (CO 2 ) emissions from power supply in the United States would reach 3,000 million metric tons (MMT) in 2020. In fact, direct power-sector CO 2 emissions in 2020 were 1,450 MMT—roughly 50% below the earlier projections. By this metric, in only 15 years the country’s power sector has gone halfway to zero emissions. Other metrics also evolved differently than projected: total consumer electricity costs (i.e., bills) were 18% lower; costs to human health and the climate were 92% and 52% lower, respectively; and the number of jobs in electricity generation was 29% higher. Economic, technical, and policy factors contributed to this success, including sectoral changes, energy efficiency, wind and solar, continued operations of the nuclear fleet, and coal-to-gas fuel switching. This historical record demonstrates the ability of technological and policy changes to set the power sector on a dramatically different emissions trajectory. Past success, however, does not trivialize the challenges that remain for further decarbonization in the power sector and beyond. Nor does it offer a specific roadmap for how best to achieve additional power-sector emissions reductions. Numerous challenges confront a zero-emissions pathway, and future strategies will likely differ from those of the past. Many recent studies have assessed how to make further progress in decarbonizing the power sector on the pathway to decarbonizing the economy as a whole. We summarize the core results of those studies, but the primary goal of this report is to highlight the progress that has already been made in reducing power-sector emissions. As the country maps out a plan for further decarbonization, experience from the past 15 years offers two central lessons. First, policy and technology advancement are imperative to achieving significant emissions reductions. Second, our ability to predict the future is limited, and so it will be crucial to adapt as we gain policy experience and as technologies advance in unexpected ways.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2020

GaAsP/Si Tandem Solar Cells: Pathway to Low-Cost, High-Efficiency Photovoltaics

Si is the dominant PV technology, now and for the foreseeable future, due to its extensive manufacturing infrastructure, supply chain, feedstock availability, and highly optimized degree of fabrication processes, which altogether has produced an economic scenario where PV electricity generation is often cheaper than conventional fossil based generation. In many places, the overarching goal of grid parity has been achieved, but further improvement in performance-cost metrics are still needed to sustain the continued LCOE reductions needed to not only compete with conventional generation, but displace it on a global scale; a matter of critical importance if we stand any hope of slowing climate change. Nevertheless, single-junction Si PV is already nearing its physical limit, both in performance and cost, and is thus cannot meet these long-term goals alone. To this end, we are working on the development of monolithic III-V/Si tandem solar cells, which improve upon the performance of pure Si by providing enhanced utilization (reduced thermalization) of high-energy photons. This architecture nominally combines the substantial existing knowledge base, manufacturing infrastructure, and low cost of Si PV with the high efficiencies afforded by the well-established multijunction approach — the only proven way to break the single-junction limit. Although the metal-halide perovskite/Si tandem architecture has garnered substantial attention in recent years, serious questions regarding reliability and service lifetime remain, whereas III-V PV has a proven track record, including in the harsh concentrator and space environments. Additionally, there are multiple fabrication approaches to producing III-V/Si tandem cells, but we are focused on monolithic epitaxial integration as it is the most likely to yield the lowest ultimate LCOE in a fully mature, scaled technology. In this work we have produced multiple generations of GaAsP/Si tandem solar cells, demonstrating a more than 10% absolute AM1.5G efficiency improvement within the time frame of the project, including two verified world records. We have done this using industry-standard fabrication methods, showing that this platform can ultimately be manufactured at scale using existing or only slightly upgraded Si and III-V tooling. Our scientific and engineering advances across a range of fundamental and applied areas – III-V/Si heteroepitaxial integration, defect control in metamorphic III-V epitaxy, fundamental materials-oriented solar cell design and modeling methodology, and more – have created clear pathways for continued advances toward the goal of >30% AM1.5G cell efficiency (and >25% module) and will serve to inform the broader research community for well beyond this immediate application. Techno-economic modeling indicates that our approach can indeed meet SunShot/SETO LCOE targets, but as with any “post-Si” technology there are difficult, but not insurmountable barriers, requiring continued focused research and development efforts.

14 SOLAR ENERGY↗

DOE OSTI2021

Upcycled "CO 2 -Negative" Concrete for Construction Functions

Electricity generation from coal-fired power plants represents 25% of total carbon dioxide (CO 2 ) emissions from the United States (1.4 billion tons of CO 2 emitted in 2015). In view of upcoming legislation that seeks to limit CO 2 emissions, in support of climate change goals, it is anticipated that such emissions will be (financially) penalized. This is of great consequence to emissions intensive sectors such as coalfired power generation which are expected to be substantially burdened by such penalties.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2021

Google/Makani Energy Kite Modeling (CRADA CRD-18-00569 Final Report)

In support of Makani’s energy kite development program, Makani engaged with NREL to develop, verify, and document a multiphysics engineering model of a megawatt-scale tethered energy kite (named KiteFAST). After the original development of KiteFAST was completed, Makani further engaged NREL to develop a software enhancement of KiteFAST to enable the dynamics modeling of an energy kite tethered to a floating offshore platform (named KiteFAST-OS). Before this project, the capability to model the aero-hydro-servo-elastic dynamics of an airborne wind energy (AWE) system with electricity generation on the flying device (fly gen) and crosswind flight operation did not exist. Such physics-based modeling capability is needed for loads analysis, structural design, and certification of energy kites. Throughout the project, an exclusive license kept KiteFAST and KiteFAST-OS available only to Makani, NREL, and its counterparts. With the ending of Makani, the KiteFAST and KiteFAST-OS software were merged into a single code base (named KiteFAST), the exclusive license was terminated, and the source code, documentation, and example models were released publicly.

17 WIND ENERGY↗

DOE OSTI2021

Albedo Measurement of the Terra Pave White Albedo Product: Cooperative Research and Development Final Report

The Terra Pave team is creating an eco-friendly, cost-effective road coating that controls dust and dirt on high-traffic roads near solar field installations to reduce the dirt cover on panels, which lowers energy output. The Terra Pave White Albedo product also has the capability to increase the amount of solar radiation reflected from the ground to the backside of bifacial PV modules, thereby increasing the amount of electricity generated. This work will quantify the amount of solar radiation reflected from the Terra Pave White albedo product by measuring its albedo, which is the ratio of the reflected radiation to the incoming radiation. Albedo is measured with two horizontal pyranometers with one ground-facing and the other sky-facing.

14 SOLAR ENERGY↗

DOE OSTI2021

Adhesion of Titanium Coatings on Additively Manufactured Stainless Steel

The ongoing global climate change crisis has brought attention to the urgent need to reduce greenhouse gas emissions from vehicles by providing alternative zero-emission fueling technologies. Prevailing vehicles are dependent on fossil fuels and contribute to climate change by creating emissions of carbon dioxide. In 2019, transportation was the largest contributing economic sector to the U.S. greenhouse gas emissions total at 29% [1]. By converting vehicle fueling to an alternative method, major reductions in greenhouse gas emissions can be achieved. Hydrogen fuel cells are one potential alternative capable of generating electricity from hydrogen while emitting only water. Several obstacles hinder the development of hydrogen fuel cells as a viable alternative, including the manufacturability of bipolar plates.

08 HYDROGEN↗

DOE OSTI2021

Charting a Path for Research and Development of Reliability and Resilience in South Asia's Power Sector

The power sector in South Asia faces several trends with the potential to impact its reliability and resilience. Rapidly increasing demand, coupled with an increasing reliance on variable renewable resources and the circular linkages with climate change points to an increasing need to understand the extent of climate impacts on both the electricity load and the electricity generation. These larger shifts are also coupled with opportunities near the grid edge that could have a large impact on system planning and operations, such as electrification of the transport sector, increased reliance on buildings to serve a broader set of loads and be flexible resources for utilities, more efficient use of industrial and agricultural loads, and growth in distributed energy resources such as rooftop solar and batteries. It is critical that as this transformation takes place that expectations for reliability and resilience of the grid continue to increase in the region. The South Asia Group for Energy (SAGE), composed of USAID, the US Department of Energy, and three national laboratories, has been tasked with providing an overview of the research and development resources necessary to understand the upcoming challenges for the power system as it pertains to reliability and resilience. This discussion paper identifies some of the key trends and connections that are important for power sector reliability and resilience and provides a starting point for eliciting feedback from power sector stakeholders about their experiences and needs.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2021

Preliminary Environmental and Financial Viability Analysis of Circular Economy Scenarios for Satisfying PV System Service Lifetime

PV deployment has grown rapidly in recent decades, and this growth is expected to continue. At the same time, the rapid increase in PV panel efficiencies offers the opportunity to repower/revamp existing installations - replacing operational, lower-efficiency panels before the end of their 30-year service lifetime with newer, higher-efficiency panels. As a result, an increasing volume of PV panels could be decommissioned well before reaching the end of their 30-year service lifetime. Two broad strategies can be applied to manage the expected increase in decommissioned PV panels: (i) recycle prematurely decommissioned panels, and (ii) prevent recycling of these panels by satisfying the typical service lifetime of 30 years through circular economy strategies such as repair and reuse. Each strategy presents an environmental and economic trade-off. Retaining and satisfying the lifetime of the older, lower-efficiency panels avoids environmental burdens from recycling or landfilling but incurs burdens from additional repair and forgoing the opportunity to install newer panels with greater electricity-generation capabilities. This study assesses whether satisfying the expected service lifetime of a PV system through circular economy scenarios generates a greater environmental and financial benefit than recycling used panels and installing newer panels with higher efficiencies. The circular economy scenarios include repair and reuse of the PV system. Specifically, the study determines whether it is better for the environment to keep a PV panel in use for its 30-year service life after accounting for potential repair and additional transportation, or to replace older panels with more efficient new ones. In addition, we explore whether satisfying the service lifetime of PV panels proves competitive with the recycling route from a financial perspective.

14 SOLAR ENERGY↗

DOE OSTI2021

Understanding Your Utility Bills: Electricity

Electricity bills can often be difficult to decipher. Depending in the electricity provider, bills can be very long and detailed or extremely short, with only a few totals listed. Different charges can appear each month with no apparent explanation of how or why they are calculated. Learning how to read electricity bills and understand why different charges are assessed is key to maximizing cost savings through energy efficiency. This document provides guidance on the basics of understanding electricity bills and covers electricity generation, rate structures, usage trends, and savings opportunities. The information in this guide can be used to help companies collect and report their energy efficiency improvements to the DOE Better Plants Program.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2021

CB10412: Bulk CWA Destruction

The objective of this project was to eliminate and/or render bulk agent unusable by a threat entity via neutralization and/or polymerization of the bulk agent using minimal quantities of additives. We proposed the in situ neutralization and polymerization of bulk chemical agents (CAs) by performing reactions in the existing CA storage container via wet chemical approaches using minimal quantities of chemical based materials. This approach does not require sophisticated equipment, fuel to power generators, electricity to power equipment, or large quantities of decontaminating materials. By utilizing the CA storage container as the batch reactor, the amount of logistical resources can be significantly reduced. Fewer personnel are required since no sophisticated equipment needs to be set up, configured, or operated. Employing the CA storage container as the batch reactor enables the capability to add materials to multiple containers in a short period of time as opposed to processing one container at a time for typical batch reactor approaches. In scenarios where a quick response is required, the material can be added to all the CA containers and left to react on its own without intervention. Any attempt to filter the CA plus material solution will increase the rate of reaction due to increased agitation of the solution.

36 MATERIALS SCIENCE↗

DOE OSTI2021

Bituminous Coal and Natural Gas to Electricity: >90% Capture Cases Technical Note

This technical note provides cost and performance estimates for post combustion carbon capture (PCCC) systems designed for greater than 90 percent capture on conventional PC- and NG-fueled power plants. The cost and performance estimates provided here were developed using the National Energy Technology Laboratory’s (NETL’s) well-documented methodology for conducting technoeconomic analysis of fossil energy conversion systems and leveraging published performance and cost projections for higher capture rate systems. Included in this technical note is a brief description of the method used to adjust select 90 percent capture cases from NETL’s Cost and Performance Baselines for Fossil Energy Systems Volume 1: Bituminous Coal and Natural Gas to Electricity, hereafter referred to as the Baseline Study. This technical note is intended to serve as an interim update to NETL’s Baseline Study cases by providing cost and performance estimates for high capture PCCC technology that can be deployed in the near-term at fossil-fueled electricity generating units.

20 FOSSIL-FUELED POWER PLANTS↗

DOE OSTI2022

Opportunities for Hybrid Wind and Solar PV Plants in India

The share of variable renewable energy (VRE) on India's grid has surpassed 100 GW, and the government has ambitious plans reach 450 GW by 2030. One strategy to increase wind and solar PV deployment is through the co-location of wind and solar PV plants to form a single hybrid power plant. Hybrid plants have the potential to reduce transmission infrastructure costs and variability in the output power profile compared to a standalone plant with a single technology, and this resource analysis aims to take a first step towards quantifying the potential savings from hybridizing wind and solar PV plants in India and the size of this opportunity. We utilize a brute-force optimization to minimize the levelized cost of energy (LCOE) for standalone wind, standalone solar PV, and hybrid wind/solar PV plants across all of India. By comparing these LCOEs, we determine that locations where hybrid plants exhibit potential cost savings and grid benefits exhibit both; a high interconnection cost and; a wind capacity factor between roughly 34% and 38%. However, because our work does not capture the value of the electricity generated by looking at energy prices, nor does it quantify the potential of hybrids to provide other value streams such as firm capacity and reserves. Further, because the work does not compare solar PV and wind hybrids to alternative generation technologies or storage systems, it cannot be considered a holistic cost-benefit analysis.

14 SOLAR ENERGY↗

DOE OSTI2022

NPD Classification Tools – User Guide NPD Explorer and NPDamCAT Apps

The existing infrastructure at non-powered dams (NPDs) presents a variety of opportunities from generating electricity and economic value to the myriad services they provide. However, it also presents a significant challenge because aging structures must be maintained, and changes to the ecosystems and river systems by NPDs must be managed. The various stakeholders interested in these opportunities and challenges require varying information about NPDs; in many cases, interest in NPDs can extend across the entire population of dams. Even when interest is more narrowly focused on an individual dam or a small subset of dams, understanding how these dams relate to the broader context of NPD infrastructure can be important. As noted in TM 2021/2155, “Each NPD has unique characteristics describing its design, operation, environmental impacts, social impacts, and economic potential. The large number of dams, the diversity of interests related to dams, the variety of dam characteristics, and the types of data required to describe dams all pose major challenges to an analysis of the entire dam population." This user guide describes two web-based tools that facilitate exploration of dams from a variety of perspectives: the NPD Explorer and the NPD Custom Analysis and Taxonomy (NPDamCAT). These tools facilitate access to information about dams and help users interact with the information, making small- to large-scale analyses more convenient for a broad set of stakeholders.

13 HYDRO ENERGY↗

DOE OSTI2022

Non-Powered Dam Custom Analysis and Taxonomy (NPDamCAT) Framework

Over 85,000 non-powered dams (NPDs) exist in the United States that provide services such as flood control, navigation, and water storage for irrigation/domestic water use (USACE 2019). The existing infrastructure of NPDs poses an opportunity for improving economic and environmental performance and generating electricity, as well as a challenge for maintaining aging structures and remediating fragmented river systems. NPD stakeholders interested in the rehabilitation, retrofit, or removal of NPDs must have the relevant information about the population of dams to support decision-making. Each NPD has unique characteristics describing its design, operation, environmental impacts, social impacts, and economic potential. The large number of dams, the diversity of interests related to dams, the variety of dam characteristics, and the types of data required to describe dams all pose major challenges to an analysis of the entire dam population.

13 HYDRO ENERGY↗

DOE OSTI2022

High Performance Equilibrium Solvers for Integrated Magnetic Fusion Simulations

With the funding provided by this award, we developed numerical codes for the study of magnetically confined plasmas for fusion applications. Accordingly, our work can be divided into two separate categories: 1) the design and analysis of novel numerical methods providing high accuracy and high efficiency; 2) the study of the equilibrium and stability of magnetically confined plasmas with some of these numerical codes, as well as the study of the nature of the turbulent behavior which may arise in the presence of instabilities. We first developed new numerical schemes based on integral equation methods for the computation of steady-state magnetic configurations in fusion experiments, providing high accuracy for the magnetic field and its derivatives, which are required for stability and turbulence calculations. We employed different integral formulations depending on the application of interest: axisymmetric or non-axisymmetric equilibria, force-free or magnetohydrodynamic equilibria, fixed-boundary equilibria or free-boundary equilibria. While efficient, these methods do not yet apply to plasma boundaries which are not smooth, a situation which is fairly common in magnetic confinement experiments. To address this temporary weakness, we also constructed a new steady-state solver based on the Hybridizable Discontinuous Galerkin (HDG) method, which provides full geometric flexibility. In addition to these numerical tools focused on steady-states, we also contributed to the improvement of the speed and accuracy of codes simulating the plasma dynamics of fusion plasmas, by developing a novel velocity space representation for the efficient solution of kinetic equations, which most accurately describe the time evolution of hot plasmas in fusion experiments. Using the tools discussed above, we studied several questions pertaining to the equilibrium and stability of magnetically confined plasmas. In particular, we derived a new simple model for axisymmetric devices called tokamaks, to predict how elongated a fusion plasma can be before it becomes unstable and collapses. We also looked at the effect of the shape of the outer plasma surface on key properties of the steady-state magnetic configurations, and how these properties impact turbulence in fusion plasmas, and the corresponding transport of momentum. Likewise, we studied the role of large localized flows on the steady-state magnetic configurations, and how they may influence plasma stability and turbulence. Non-axisymmetric steady-state magnetic configurations are inherently more complex than axisymmetric steady-state configurations, and the subject of ongoing controversies regarding the regularity of the equations determining such steady-states, and their solutions. Implementing an existing NYU code in a new geometry, we studied the nature of the singularity of the solutions observed in the code, and methods to eliminate them. Our main conclusion is that by appropriately tailoring the plasma boundary, it is possible to eliminate the singularities otherwise appearing in our simulations, and to obtain steady-states which appear to be smooth. To gain further insights on incompletely understood turbulence phenomena, we proposed a new reduced model capturing most of these phenomena, which is simple enough to not require expensive numerical simulations on massive supercomputers to investigate them. We demonstrated the strong similarity between our simulations and published results obtained from computationally expensive simulations, and plan to rely on our reduced model to identify the key mechanisms determining the evolution and strength turbulent driven transport in fusion plasmas. Finally, we proposed a new framework for tokamak reactor design studies, enabling us to consider the relative merits of steady-state versus pulsed fusion reactors. We found that pulsed fusion reactors may benefit most from recent advances in magnet technology, and the availability of very high field magnets. As such, they may become more desirable than steady-state tokamak reactors for cost efficient electricity generation.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗