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Business Opportunities in Clean Energy Supply Chains: Guidebook for Small and Medium-Sized Automotive Suppliers

This is the final report for the referenced TCF award which ran from Oct. 2019 through Jan. 2024 in conjunction with the industry partner Swift Solar. The long duration of the program was due to several factors including the pandemic and a technical work stoppage due to changes in the scope. Additionally, Swift’s business focus shifted during the course of the program. As a result of these factors, this program underwent two distinct modifications that dramatically changed the work scope. The following report is organized into three separate sections, each of which addresses a distinct work scope. Those scope changes, what necessitated them, and any new tasks/milestones are given, briefly, at the top of each section. The work performed was research on the hybrid halide perovskites (HHP), both the absorber material itself as well as other material layers that are required in a full device stack. At the start of the period of performance, there were two distinct challenges that we sought to address: (1) a wide band gap absorber (>1.6 eV), and (2) a recombination layer for tandem devices that provided good sequestration of the individual cell absorber materials in their respective device layers. NREL had previously published, and patented, advancements in both of these areas and they were the focus of much of the work throughout the program. The auto manufacturing space is evolving quickly. Sales of various electrified vehicles (xEVs) continue to grow steadily, which has medium to long-term ramifications for the thousands of U.S. manufacturers and hundreds of thousands of workers that contribute to the domestic automotive supply chain. In tandem with this growth in xEV sales, domestic clean energy manufacturing is surging (both for the xEV supply chain and other technologies), with public incentives spurring billions in private sector investment. Moreover, the next 2–3 years will see new and expanded industrial facilities come online to make products like hydrogen electrolyzers, solar panels, batteries, advanced electronics—and will create new supply chain needs and business opportunities as they do. DOE’s Office of Manufacturing and Energy Supply Chains (MESC) and Argonne National Laboratory developed this report to help automotive manufacturers—alongside various business support partners— understand these trends and their response options, and to make the most of current federal assistance programs for manufacturers. These market changes may create opportunities for small- and medium-sized manufacturers (SMMs) to expand production, grow profit margins, and diversify their businesses. For instance, SMMs could take advantage of engineering and process design similarities with new end-use industries that might enable greater business growth and stability as markets continue to change.

14 SOLAR ENERGY

High Speed Medium Voltage CHP System with Advanced Grid Support

The project was a collaboration between Clemson University and TECO Westinghouse Motor Company. The goal of the project was to develop a medium voltage commercial grid-tied system with advanced grid support functions. Current state-of-the-art in medium voltage, multi-megawatt power electronic systems do not support advanced grid functions, traditionally due to power electronic limitations and required applications. The developed system is capable of interacting with the power system at the distribution level to efficiently integrate gas turbine generation systems or any other ac generation system with up to 20MWe of power production capacity. This project demonstrated a high level of technical readiness of the 1MW, 500Hz, 15000 RPM high frequency Combined Heat and Power (CHP) generator and electric machine system, utilizing advanced grid support functions required by IEEE Std. 1547-2018.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI

Spatially Resolved Domicile Charging Demands for Light-, Medium-, and Heavy-Duty Electric Vehicles in Virginia

The use of plug-in electric vehicles (PEVs) and resulting grid impacts are likely to grow rapidly, and evaluation of optimal smart charge management and grid integration strategies is warranted now. Evaluating distribution grid impacts requires fine-grained models of PEV operations to estimate charging loads across diverse vehicles at high spatial resolution. We propose such a model and consider a high-electrification scenario in Richmond and Newport News, Virginia. Our framework considers four categories of vehicle that are amenable to early aggressive electrification: light-duty passenger vehicles (LDV), trucks and vans with a focus on delivery or other local operations, school buses, and transit buses. These vehicles have a relatively consistent domicile, reducing the need for public charging infrastructure rollout to electrify. We apply a recent LDV model and propose new models for each vocation of medium- and heavy-duty vehicle, leveraging telematics data. We demonstrate our framework in Virginia and find energy demands in the region may total 15 GWh day, with most consumed by LDV. However, considering power demand at high spatial resolution reveals a different trend: LDVs have relatively small peak loads at specific sites (peak site demand around 800 kW) compared to average and high demand medium- and heavy-duty vehicle charging sites (peak site demand around 6,000 kW at a transit bus depot, 1,500 kW at a local freight hub, and 1,000 kW at a school). Our framework yields insights on the relative impacts of each vocation and enables future work to tailor grid integration strategies to each vehicle category.

33 ADVANCED PROPULSION SYSTEMS

To investigate the reciprocal interactions between dielectric barrier discharges and different biological targets in cell culture medium

The objective of this project was to investigate the dynamic interactions between non-thermal plasma (NTP) and biological targets suspended in a physiological liquid medium. The experiments under this collaborative study were designed to combine theoretical and experimental approaches to test the hypothesis that when living cells (and the growth medium surrounding them) encounter plasma, they reciprocally and dynamically modify each other.

59 BASIC BIOLOGICAL SCIENCES

Evaluation of Damage in Medium Voltage Cable Using Machine Learning

Developments in cable test instrumentation coupled with artificial intelligence and machine learning (ML) to aid in interpretation of cable test signals supports the feasibility for automated analysis of reflectometry tests for low voltage power cables. This work seeks to leverage prior ML work and success for low voltage cables to evaluate potential application to medium voltage (2kV to 10kV) installations. The Accelerated and Real-Time Environmental Nodal Assessment (ARENA) Cable Motor Test Bed at Pacific Northwest National Laboratory (PNNL) was used to test a medium voltage cable with several types of damage including thermal aging and low resistance conductor-to-shield faults. The cable was tested using an inductive clamshell coupler to protect the test instruments from the energized cable voltages that would damage the test instruments if coupled directly to the energized conductor.

42 ENGINEERING

A theory of scattering from irregularities in a magneto-ionic medium.

Attempt to determine what effect the anisotropy of the background medium will have on the scattering of electromagnetic waves from ionospheric irregularities. A Green's function is used to solve the scattered power using a certain bistatic geometry. Since the medium is anisotropic, cross-mode scattering in addition to self-mode scattering is possible. Several examples are given.

Simonich, D. M.

The influence of the ionized medium on synchrotron emission in interstellar space.

The effect of the ionized gas on synchrotron emission in the interstellar medium is investigated. A detailed calculation of the synchrotron emissivity of cosmic electrons, assumed to have an isotropic pitch-angle distribution in a uniform magnetic field, is made as a function of frequency and observation angle with respect to the field. The results are presented both as a local emissivity and as an intensity, the latter obtained by neglecting free-free absorption in the interstellar medium and by assuming that the emissivity is constant along the line of sight. The comparison of these results with previous studies on the nature of the low-frequency turnover of the galactic nonthermal radio background reveals that, except if the component perpendicular to the line of sight of the interstellar magnetic field is small (less than 1 microgauss), or if the cosmic-ray electron spectrum is cut off at energies below a few hundred MeV, the suppression of synchrotron emission by the ambient electrons has in general a lesser effect than free-free absorption by these electrons, and that in some cases this suppression effect is almost entirely negligible.

Ramaty, R.

Analysis of shape of porous cooled medium for an imposed surface heat flux and temperature

The surface of a porous cooled medium is to be maintained at a specified design temperature while being subjected to uniform heating by an external source. An analytical method is given for determining the shape of the medium surface that will satisfy these boundary conditions. The analysis accounts for temperature dependent variations of fluid density and viscosity and for temperature dependent matrix thermal conductivity. The energy equation is combined with Darcy's law in such a way that a potential can be defined that satisfies Laplace's equation. All of the heat-transfer and flow quantities are expressed in terms of this potential. The determination of the shape of the porous cooled region is thereby reduced to a free-boundary problem such as in inviscid free jet theory. Two illustrative examples are carried out: a porous leading edge with coolant supplied through a slot and a porous cooled duct with a rectangular outer boundary.

Siegel, R.

Synthetic sea water - An improved stress corrosion test medium for aluminum alloys

A major problem in evaluating the stress corrosion cracking resistance of aluminum alloys by alternate immersion in 3.5 percent salt (NaCl) water is excessive pitting corrosion. Several methods were examined to eliminate this problem and to find an improved accelerated test medium. These included the addition of chromate inhibitors, surface treatment of specimens, and immersion in synthetic sea water. The results indicate that alternate immersion in synthetic sea water is a very promising stress corrosion test medium. Neither chromate inhibitors nor surface treatment (anodize and alodine) of the aluminum specimens improved the performance of alternate immersion in 3.5 percent salt water sufficiently to be classified as an effective stress corrosion test method.

Humphries, T. S.

Resistive diffusion of force-free magnetic fields in a passive medium.

We consider the resistive diffusion of a force-free magnetic field in a tenuous compressible medium, which is free to move to accommodate the changing magnetic-field configuration. This process is nonlinear, contrary to the usual magnetic field diffusion in a fixed medium. We show that the force-free magnetic field may evolve slowly for an extended period of time, whereupon it abruptly develops steep gradients and passes into an explosive phase. We suggest that it is this process that sets the stage for the onset of solar flares.

Low, B. C.

Monte Carlo investigation of transient acoustic fields in partially or completely bounded medium

A simple repetitive calculation was used to investigate what happens to the field in terms of the signal paths of disturbances originating from the energy source. The computation allowed the field to be reconstructed as a function of space and time on a statistical basis. The suggested Monte Carlo method is in response to the need for a numerical method to supplement analytical methods of solution which are only valid when the boundaries have simple shapes, rather than for a medium that is bounded. For the analysis, a suitable model was created from which was developed an algorithm for the estimation of acoustic pressure variations in the region under investigation. The validity of the technique was demonstrated by analysis of simple physical models with the aid of a digital computer. The Monte Carlo method is applicable to a medium which is homogeneous and is enclosed by either rectangular or curved boundaries.

Thanedar, B. D.

Depolarization of an uncollimated laser beam in a turbulent medium

The depolarization of a beam wave, with Gaussian intensity distribution and arbitrary divergence, propagating in a turbulent medium is considered. The correlation function of the depolarized component of the beam is determined. The mean-square depolarization fluctuation is then determined for a medium characterized by a Kolmogorov spectrum. If the beam is assumed to be collimated, this expression reduces to that of Collett and Alferness; if the plane-wave limiting case of the Gaussian beam is taken, the results in this paper agree with those of Strohbehn. The results show that off the beam axis the depolarization can be greater than for the plane wave, and that near the beam focal point the depolarization may decrease by orders of magnitude.

Chang, F. C.

Read-only optical storage medium

Photosensitive recording medium consists of thin-film silicone resin deposited on photoconductive substrate. Medium is useful for holographic interferometry studies.

Gange, R. A.

Medium resolution stellar spectra in the two-micron region

The astrophysical implications of available medium resolution spectra in the limited wavelength range from 1.9 to 2.5 microns are considered. Observational techniques are discussed along with features observable at medium resolution. Attention is given to molecular bands of carbon monoxide, water, and cyanogen. Identified atomic features are related to hydrogen, helium, silicon, magnesium, and titanium. Empirical band strength-color relationships are examined, taking into account carbon monoxide in G5-M8 giants and supergiants, the isotopic C-12/C-13 abundance ratio, and water vapor band strengths in late-type stars.

Hyland, A. R.

On the ionization of the intercloud medium by runaway O-B stars

H II regions around seven high-velocity stars of type O5 to B1 (lambda Cep, xi Per, 68 Cyg, alpha Cam, AE Aur, zeta Oph, mu Col) are investigated assuming 'on-the-spot' reabsorption of the diffuse UV and time-dependent cooling and recombination behind the stars. Ratios of column densities integrated through the H II regions are obtained for stationary and moving stars, and the ionization structure is calculated for an H II region around a runaway star moving perpendicular to the galactic plane. The total volume ionized is found to be practically independent of the star's velocity. Global properties of the intercloud medium are examined; it is found that the presence of clouds may reduce the volume ionized by as much as a factor of 7 and that as much as 30% of the total ionizing radiation from early-type stars may leak out of the galaxy. Copernicus satellite observations are shown to be consistent with lines of sight crossing only the H II regions around the observed stars and a neutral intercloud medium as well as with the existence of a 'hole' in the distribution of O-B5 stars in the vicinity of the sun.

Thuan, T. X.

Satellite measurements of ion composition and temperatures in the topside ionosphere during medium solar activity

Information on both ion density and temperature is obtained from analysis of Retarding Potential Analyzer data from the OGO-4 and Explorer-31 satellites. Results obtained from data in the altitude range of 700-2000 km during medium solar activity are presented. An attempt is made to describe the major altitude variations of ion densities and temperatures at middle and low latitudes. The transition heights, where the heavier and lighter ions are equal, are found to be about 1600 and 1300 km at middle and low latitudes, respectively, for daytime and 700 km at night for middle latitudes. Based on the observed data and using diffusive equilibrium as a first-order approximation, topside ionospheric composition models are given for medium solar activity.

Goel, M. K.