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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

Demonstration of a Fiber Optic Regression Probe in a High-Temperature Flow

The capability to provide localized, real-time monitoring of material regression rates in various applications has the potential to provide a new stream of data for development testing of various components and systems, as well as serving as a monitoring tool in flight applications. These applications include, but are not limited to, the regression of a combusting solid fuel surface, the ablation of the throat in a chemical rocket or the heat shield of an aeroshell, and the monitoring of erosion in long-life plasma thrusters. The rate of regression in the first application is very fast, while the second and third are increasingly slower. A recent fundamental sensor development effort has led to a novel regression, erosion, and ablation sensor technology (REAST). The REAST sensor allows for measurement of real-time surface erosion rates at a discrete surface location. The sensor is optical, using two different, co-located fiber-optics to perform the regression measurement. The disparate optical transmission properties of the two fiber-optics makes it possible to measure the regression rate by monitoring the relative light attenuation through the fibers. As the fibers regress along with the parent material in which they are embedded, the relative light intensities through the two fibers changes, providing a measure of the regression rate. The optical nature of the system makes it relatively easy to use in a variety of harsh, high temperature environments, and it is also unaffected by the presence of electric and magnetic fields. In addition, the sensor could be used to perform optical spectroscopy on the light emitted by a process and collected by fibers, giving localized measurements of various properties. The capability to perform an in-situ measurement of material regression rates is useful in addressing a variety of physical issues in various applications. An in-situ measurement allows for real-time data regarding the erosion rates, providing a quick method for empirically anchoring any analysis geared towards lifetime qualification. Erosion rate data over an operating envelope could also be useful in the modeling detailed physical processes. The sensor has been embedded in many regressing media to demonstrate the capabilities in a number of regressing environments. In the present work, sensors were installed in the eroding/regressing throat region of a converging-diverging flow, with the working gas heated to high temperatures by means of a high-pressure arc discharge at steady-state discharge power levels up to 500 kW. The amount of regression observed in each material sample was quantified using a later profilometer, which was compared to the in-situ erosion measurements to demonstrate the efficacy of the measurement technique in very harsh, high-temperature environments.

Korman, Valentin↗
DOE OSTI2022

A 100-Mrad (Si) JFET-based Sensing and Communications System for Extreme Nuclear Instrumentation Environments

Dry cask storage is one of two storage methods approved by the U.S. Nuclear Regulatory Commission for spent fuel after removal from reactor cores. Dry casks consist of a stainless steel canister enclosed in a concrete overpack to contain the hazardous radioactive spent fuel rods and provide radiation shielding. Monitoring spent fuel storage casks is desired to ensure the safe containment of the enclosed spent fuel, but is very difficult due to the related harsh temperature and radiation environment. The sensors and associated electronics to monitor temperature, pressure, and/or radiation need to survive high temperatures and radiation doses for extended time periods. For this reason, there is a severe need for radiation-hardened electrical systems that survive well beyond the existing capabilities of commercially available radiation-rated electronic components, which have primarily been developed for space applications. Junction-gate field-effect transistor (JFET) devices are inherently radiation hardened [exceeding 100 Mrad (Si)]. Additionally, when JFETs are used as building blocks for sensing and communication electronics (i.e., oscillators, amplifiers, filters, and mixers), inherently radiation-hardened circuits can be achieved. To this end, JFET-based radiation-hardened electronics interfacing with cask-embedded sensors capable of driving modulated sensor signals through a stainless steel barrier were designed and tested at a dose rate of approximately 500 krad/h (Si) to beyond a 200-Mrad (Si) total ionizing dose. After 200 Mrad (Si), the sensor and communication circuit signals were correctly decoded at the receiver despite oscillator drift. The results from this experiment demonstrate the potential for creating more complex radiation-hardened JFET-based electrical systems for nuclear environments.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRSDate not supplied

Next Generation Big Data Storage for Long Space Missions

This paper presents the results of the HELIOS (Hardened Extremely Long Life In-formation Optical Storage) mission on the International Space Station (ISS) which tested a unique solution for the long-term storage and retrieval of data in space. For this mission Creative Technology (CTech) developed test media—termed WORF (Write Once, Read Forever)—to validate whether this patented technology will survive all critical parameters for harsh space-based environments including microgravity and ionizing radiation. The HELIOS experiment confirmed that the WORF media is impervious to ionizing radiation, microgravity, solar (plasma) eruptions, and the stress from 8 Gs of the launch including extreme temperature expo-sure. The principal results indicate that there has been no discernible degradation of the media after 8 months on the ISS as compared to a control set of media stored on the ground. This data validated the media’s survivability for harsh space environments for long-term and deep space missions. In addition to the space environment, we are confident that WORF technology can be used for data storage where space-related and other long-term or archival integrity is critical such as: geospatial collections from satellites; space weather archives; past, ongoing, and future space mission media and documentation files; the deep space Gate-way program; as well as Big Data applications such as the Vera C. Rubin astronomical observatory (formerly the LSST). WORF technology for the HELIOS experiment uses a proven archival media, redesigned, re-purposed and patented by CTech to store digital data for long periods, measured in decades and possibly centuries. The media stores standing waves embedded in a substrate that capture the precise col-ors or wavelengths projected onto the media. The colors represent numerical data, with each data location storing multiple superimposed wavelengths, which facilitate the storage of multiple data bytes (rather than just zeros and ones); advanced mathematical permutations allow for extremely large data density equal to or greater than contemporary data storage de-vices. These colors cannot fade or degrade over time since the standing waves are physically stabilized (fully oxidized) metallic silver; no dyes are embedded for this storage system, and silver ions resist micro-bacterial and fungal contamination

Rodney Grubbs↗
NASA NTRS2018

Laser power supply thermo-structural analysis for the Mars 2020 rover

Operation of the Laser Power Supply (LPS) module provides the dual challenge of high power dissipation, and the need for strict dielectric isolation, while needing to survive in an environment on Mars that will see a chilly night-time temperature of -123°C, and to a daytime instrument environment in excess of 50°C. Additionally, power restrictions prevent the use of survival heating during the night. The harsh mechanical vibration environment of launch and landing provides an additional challenge to reliability. A multi-physics simulation was created that took into account temperature property variations, as well as solving the transient analysis that also included rapid variation in power-pulsing during the operation of the laser. The steady state analysis employed a more traditional finite element based analysis, but with provisions for Mars gas convection and thermal radiation.

Tuman, David↗
NASA NTRS2018

Mars 2020 Rover Laser Power Supply Thermomechanical Analysis

Operation of the Laser Power Supply (LPS) module provides the dual challenge of high power dissipation, and the need for strict dielectric isolation, while needing to survive in an environment on Mars that will see a chilly night-time temperature of -123°C, and to a daytime instrument environment in excess of 50°C. Additionally, power restrictions prevent the use of survival heating during the night. The harsh mechanical vibration environment of launch and landing provides an additional challenge to reliability. A multi-physics simulation was created that took into account temperature property variations, as well as solving the transient analysis that also included rapid variation in power-pulsing during the operation of the laser. The steady state analysis employed a more traditional finite element based analysis, but with provisions for Mars gas convection and thermal radiation.

Tuman, David↗
NASA NTRSDate not supplied

Cleanroom Microbes Survive Drying, Vacuum, and Proton Irradiation

Introduction : The goal of planetary protection at NASA is to mitigate the risk of contaminating sensitive target bodies with biological life. While many cleaning procedures have been put in place to reduce bioburden on spacecraft, microbes are experts at evolving to survive harsh conditions. Specifically, the dry, low-nutrient environment of a cleanroom (commonly used for assembly of spacecraft) can represent an environment where extremophiles can survive. Methods : Scientists at NASA MSFC wished to gather a snapshot of the microbial population within a variety of cleanrooms on site. A study was undertaken to collect air, surface, and floor samples from clean-rooms and isolate unique morphologies. From this study, 95 isolates were collected and saved in a microbial library. About 86% of these were identified at least to a genus level. Following identification, 24 microbes were selected, based on a literature review, as potential extremophiles. These were grown in liquid cultures, diluted to a set optical density, washed with water, and then applied to a sterilized Kapton coupon. Droplets were allowed to dry overnight in a biosafety cabinet. Coupons were then installed in a pelletron and pumped down to high vacuum (~1E-6 Torr). Samples were then subjected 100 keV protons at a fluence of 2x10 15 p+/cm 2 up to 4x10 15 p+/cm 2 . Following exposure, samples were returned to the microbiology lab where they were pro-cessed by submerging in water, vortexing, and then plating either droplets or spread plates. Recovery data collected was qualitative with a ranking or +, minor, or – for growth. Some selected radiotolerant strains were sequenced using the Illumina sequencing platform. The resulting genomes were annotated with the Rapid Annotations using Subsystems Technology (RAST) server and analyzed for conserved and unique stress response relevant genomic signatures to identify clues related to specific tolerances. Results and Discussion : After five rounds of proton radiation, we narrowed our isolates to five, non-spore forming bacteria that demonstrated survival: Arthrobacter koreensis, Paenarthrobacter nitroguajacolicus, Mycetocola manganoxydans , and an Erwinia sp. Furthermore, we exposed these four microbes to 254 nm wavelength light at an intensity of 80 W/m 2 at a distance of ~18 cm for 10 minutes. Only A. koreensis demonstrated survival following UV exposure. Finally, we performed whole genome sequencing on the four strains to look for genetic markers of stress resistance. When we compared the genomes of the four strains, we found that genes coding for GGDEF and EAL domains with PAS/PAC sensors were only found in A. koreensis . These domains, modulated by PAS/PAC sensors, are hypothesized to facilitate survival under drying, desiccation, and proton irradiation. Drying and Desiccation : PAS domains sense hydration changes and modulate GGDEF and EAL domain activity to adjust c-di-GMP levels, enhancing resistance to desiccation. For instance, in Pseudomonas aeruginosa , the PAS domain of RbdA modulates activity under varying hydration conditions, affecting stress responses [1]. Proton Irradiation : Proton irradiation causes oxidative stress, leading to ROS generation. PAS domains detect this stress and modulate GGDEF and EAL domains to manage oxidative stress responses. In Shewanella , EAL domain proteins modulated by PAS sensors help bacteria adapt to extreme conditions [2]. These genes upregulate other stress response genes, protecting membrane function, protein stability, DNA repair, and antioxidant defenses. The modulation of c-di-GMP by PAS domains is crucial for bacterial adaptation to stress conditions, enabling dynamic physio-logical adjustments [3]. Understanding these mechanisms provides insights into bacterial stress responses and strategies for controlling bacterial growth [4]. Conclusions : These findings indicate that clean-rooms harbor extremophile microbes that may be able to survive conditions in deep space. Furthermore, while we identified certain stress-response genes that may be at least partly responsible for the phenotypes observed in this study, there are likely unidentified genes or characteristics about A. koreensis , and other bacteria, that may allow them to survive in harsh environments. Future studies will focus on identifying these unknown genes and characteristics, further elucidating the mechanisms of extremophile survival and potentially informing the development of new biotechnologies for space exploration and other extreme environments.

Chelsi Cassilly↗
NASA NTRS2018

Mission Concept for a Europa Lander

A NASA HQ-directed study team led by the Jet Propulsion Laboratory (JPL) with partners including Applied Physics Lab, Marshall Space Flight Center, Goddard Space Flight Center, Langley Research Center and Sandia National Laboratory has recently presented a mission concept for a Europa Lander that would search for bio-signatures and signs of life in the near-subsurface of the Jovian moon. The mission would follow the Europa Clipper multiple-flyby mission, planned for launch in June of 2022, which would provide reconnaissance imagery and other data to the Lander for use in selecting a scientifically compelling site and certifying it for engineering safety. The Europa Lander concept accommodates the Model Payload identified by the Europa Lander Science Definition Team (SDT) and documented in the Europa Lander Study 2016 Report released in February of 2017. The currently envisioned Europa Lander would launch on an SLS Block 1B as early as October of 2025 into a VEGA trajectory, arriving in the Jovian system as early as July of 2030. The baseline design of the integrated flight system includes a dedicated Carrier and Relay Stage, a Deorbit Vehicle composed of a Deorbit Stage consisting of a solid rocket motor (SRM), an MSL-like sky-crane Descent Stage, and a Lander which accommodates the instrument suite. The Lander would be powered by primary batteries over a 20-day surface mission. The science goals envisioned by the SDT require five samples taken from a depth of 10cm, a depth chosen to ensure minimal radiation processing of the potential biomarkers. Mission challenges include the large launch mass, unknown terrain topography, surface composition and materials properties, the high radiation environment, and complying with stringent planetary protection requirements. The mission concept uses a strategy of early risk reduction and overlapping requirements to provide robustness to harsh and uncertain environments. Early risk reduction efforts are aimed at maturing technologies associated with the sampling system, the intelligent landing system, high specific energy batteries, low mass and power motor controllers, and a thermal sterilization system.

Dooley, Jennifer↗
NASA NTRSDate not supplied

Simulating Micrometeoroid Bombardment on Mercury: Identifying New Space Weathering Features in the Laboratory

Airless bodies are continually exposed to the harsh interplanetary space environment, causing the alteration of their surfaces through a process known as space weathering (SW). SW is dominated by solar wind irradiation and micrometeoroid bombardment, which together alter the spectral, microstructural, and chemical characteristics of grains on the surface of airless bodies. The effects of SW are variable and depend on the heliocentric distance and the initial composition of the planetary surface, among other factors. On the Moon and S- type asteroids, it is well established that SW darkens and reddens the surface of these bodies and attenuates absorption bands across the Vis-NIR wavelengths. These spectral effects are largely the result of the production of metallic Fe nanoparticles (npFe). However, Mercury’s SW environment is unique compared to the Moon and S-type asteroids. Mercury is a geochemical endmember, with a surface composition low in Fe (<2 wt.%) and enriched in volatile components, including regions of the surface hypothesized to contain up to 4 wt.% graphite in the low reflectance material (LRM). In fact, the presence of graphite on Mercury has been hypothesized to act as a reducing agent for silicates during SW to produce Si-bearing Fe-rich metal. In addition, its location in the solar system exposes Mercury to an extreme SW environment, with the surface of the planet experiencing an intense solar wind flux and higher flux and velocity of micrometeoroid impactors compared to the Moon and S-type asteroids. The effects that such harsh SW has on materials with the unique compositional characteristics of Mercury are not well constrained. To better understand SW at Mercury, we must investigate these processes in the laboratory. Here, we present the results of our analyses of the spectral, microstructural and chemical characteristics of Mercury analog samples irradiated by pulsed laser to simulate the short duration, high temperature events associated with micrometeoroid impacts.

Nick Bott↗
NASA NTRS2017

Taking SiC Power Devices to the Final Frontier: Addressing Challenges of the Space Radiation Environment

Silicon carbide power device technology has the potential to enable a new generation of aerospace power systems that demand high efficiency, rapid switching, and reduced mass and volume in order to expand space-based capabilities. For this potential to be realized, SiC devices must be capable of withstanding the harsh space radiation environment. Commercial SiC components exhibit high tolerance to total ionizing dose but to date, have not performed well under exposure to heavy ion radiation representative of the on-orbit galactic cosmic rays. Insertion of SiC power device technology into space applications to achieve breakthrough performance gains will require intentional development of components hardened to the effects of these highly-energetic heavy ions. This work presents heavy-ion test data obtained by the authors over the past several years for discrete SiC power MOSFETs, JFETs, and diodes in order to increase the body of knowledge and understanding that will facilitate hardening of this technology to space radiation effects. Specifically, heavy-ion irradiation data taken under different bias, temperature, and ion beam conditions is presented for devices from different manufacturers, and the emerging patterns discussed.

Power semiconductor devices↗
DOE OSTI2022

Status Update for the Canister Deposition Field Demonstration

This report updates the high-level test plan for evaluating surface deposition on three commercial 32PTH2 spent nuclear fuel (SNF) canisters inside NUTECH Horizontal Modular Storage (NUHOMS) Advanced Horizontal Storage Modules (AHSMs) from Orano (formerly Transnuclear Inc.) and provides a description of the surface characterization activities that have been conducted to date. The details contained in this report represent the best designs and approaches explored for testing as of this publication. Given the rapidly developing nature of this test program, some of these plans may change to accommodate new objectives or requirements. The goal of the testing is to collect highly defensible and detailed dust deposition measurements from the surface of dry storage canisters in a marine coastal environment to guide chloride-induced stress corrosion crack (CISCC) research. To facilitate surface sampling, the otherwise highly prototypic dry storage systems will not contain SNF but rather will be electrically heated to mimic the decay heat and thermal hydraulic environment. Test and heater design is supported by detailed computational fluid dynamics modeling. Instrumentation throughout the canister, storage module, and environment will provide extensive information about thermal-hydraulic behavior. Manual sampling over a comprehensive portion of the canister surface at regular time intervals will offer a high-fidelity quantification of the conditions experienced in a harsh yet realistic environment. Functional testing of the finalized heater assemblies and test apparatus is set to begin in December 2022. The proposed delivery of the canisters to the host test site is June/July 2023, which is well ahead of when the AHSM installations would be completed.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2026

Degradation of Magnetic Materials for High-Temperature Active Magnetic Bearing Applications in CO₂-Based Environments

High-temperature Active Magnetic Bearings (AMBs) are a promising alternative to conventional bearings in hermetically sealed turbomachinery for supercritical CO₂ (sCO₂) systems. They offer reduced CO₂ leakage, lower windage losses, enhanced misalignment tolerance, reduced wear, and built-in diagnostic capabilities. A critical challenge, however, is ensuring long-term material stability in harsh CO₂-rich environments. This study investigated the degradation behavior of permanent and soft magnetic materials (Alnico 9C, Alnico 5-7C, SmCo 18-T550, Hiperco-50, and coated variants) after up to 6,000 hours of exposure in gaseous CO₂, sCO₂, or air at 450 °C and 550 °C. The evaluation included post-exposure mass change measurements, scanning electron microscopy (SEM) analysis, and magnetic property assessments. The results demonstrate oxidation rates, microstructural evolution, and retention of magnetic performance across conditions. The findings offer essential insights into the thermal corrosion behavior of magnetic materials under CO₂ rich environments and serve as a reference for material selection in AMB system designs.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Preliminary Test Design and Plan for a Canister Deposition Field Demonstration

This report provides a high-level test plan for deploying three commercial 32PTH2 spent nuclear fuel (SNF) canisters inside NUHOMS Advanced Horizontal Storage Modules (AHSM) from Orano (formerly Transnuclear Inc.). The details contained in this report represent the best designs and approaches explored for testing as of this publication. Given the rapidly developing nature of this test program, some of these plans may change to accommodate new objectives or adapt in response to conflicting requirements. The goal of the testing is to collect highly defensible and detailed surface deposition measurements from the surface of dry storage systems in a marine coastal environment to guide chloride-induced stress corrosion crack (CISCC) research. To facilitate surface sampling, the otherwise highly prototypic dry storage systems will not contain SNF but rather will be electrically heated to mimic the thermal-hydraulic environment. Instrumentation throughout the canister, storage module, and environment will provide an extensive amount of information for the use of model validation. Manual sampling over a comprehensive portion of the canister surface at regular time intervals will offer a high-fidelity quantification of the conditions experienced in a harsh yet realistic environment.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Status Update for the Canister Deposition Field Demonstration

This report updates the high-level test plan for evaluating surface deposition on three commercial 32PTH2 spent nuclear fuel (SNF) canisters inside NUTECH Horizontal Modular Storage (NUHOMS) Advanced Horizontal Storage Modules (AHSM) from Orano (formerly Transnuclear Inc.) and provides a description of the surface characterization activities that have been conducted to date. The details contained in this report represent the best designs and approaches explored for testing as of this publication. Given the rapidly developing nature of this test program, some of these plans may change to accommodate new objectives or requirements. The goal of the testing is to collect highly defensible and detailed surface deposition measurements from the surface of dry storage canisters in a marine coastal environment to guide chloride-induced stress corrosion crack (CISCC) research. To facilitate surface sampling, the otherwise highly prototypic dry storage systems will not contain SNF but rather will be electrically heated to mimic the thermal-hydraulic-environment. Instrumentation throughout the canister, storage module, and environment will provide an extensive amount of information for the use of model validation. Manual sampling over a comprehensive portion of the canister surface at regular time intervals will offer a high-fidelity quantification of the conditions experienced in a harsh yet realistic environment.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2001

Organic Materials Ionizing Radiation Susceptibility for the Outer Planet/Solar Probe Radioisotope Power Source

The Department of Energy is considering the current Stirling Technology Corporation 55 We Stirling Technology Demonstration Convertor as a baseline option for an advanced radioisotope power source for the Outer Planets/Solar Probe project of Jet Propulsion Laboratory and other missions. However, since the Technology Demonstration Convertor contains organic materials chosen without any special consideration of flight readiness, and without any consideration of the extremely high radiation environment of Europa, a preliminary investigation was performed to address the radiation susceptibility of the current organic materials used in the Technology Demonstration Convertor. This report documents the results of the investigation. The results of the investigation show that candidate replacement materials have been identified to be acceptable in the harsh Europa radiation environment.

Golliher, Eric L.↗
NASA NTRS2015

Electrostatic Discharge Testing of Carbon Composite Solar Array Panels for Use in the Jovian Environment

NASA is currently considering a mission to investigate the moons of Jupiter. When designing a spacecraft for this type of mission, there are a number of engineering challenges, especially if the mission chooses to utilize solar arrays to provide the spacecraft power. In order for solar arrays to be feasible for the mission, their total mass needed to fit within the total budget for the mission, which strongly suggested the use of carbon composite facesheets on an aluminum core for the panel structure. While these composite structures are a good functional substitution for the metallic materials they replace, they present unique challenges when interacting with the harsh Jovian space environment. As a composite material, they are composed of more than one material and can show different base properties depending in differing conditions. Looking at the electrical properties, in an Earth-based environment the carbon component of the composite dominates the response of the material to external stimulus. Under these conditions, the structures strongly resembles a conductor. In the Jovian environment, with temperatures reaching 50K and under the bombardment from energetic electrons, the non-conducting pre-preg binding materials may come to the forefront and change the perceived response. Before selecting solar arrays as the baseline power source for a mission to Jupiter, the response of the carbon composites to energetic electrons while held at cryogenic temperatures needed to be determined. A series of tests were devised to exam the response of a sample solar array panel composed of an M55J carbon weave layup with an RS-3 pre-preg binder. Test coupons were fabricated and exposed to electrons ranging from 10 keV to 100 keV, at 1 nA/cm2, while being held at cryogenic temperatures. While under electron bombardment, electrical discharges were observed and recorded with the majority of discharges occurring with electron energies of 25 keV. A decrease in temperature to liquid nitrogen temperatures showed a marked increase in the magnitude of these discharges. The results indicate that dielectric discharges are primarily produced due to the presence of large regions of the non-conductive pre-preg on the surface of the carbon sheets. The frequency and magnitude of discharges decreased when layers of the pre-preg material were removed from the composite surface. These tests indicate that solar array panels may be used in the Jovian environment, but that electrostatic discharges can be expected on the carbon composite solar arrays.

Jupiter↗
DOE OSTI2024

Monitoring of Photovoltaic (PV) Performance and Degradation: Integrated Renewable Energy Systems (IRES) - PV Monitoring Task

The Integrated Renewable Energy System (IRES) testbed demonstration at the Pacific Northwest National Laboratory (PNNL) Sequim campus includes development of a suite of capabilities for tracking the performance of photovoltaic (PV) renewable energy components located on a floating platform (floating PV) and on a shoreline building rooftop. The marine environment represents potentially harsh and corrosive conditions for PV modules. Compared to terrestrial PV, potential concerns for offshore PV arising from high humidity and occasional contact with saltwater, marine wildlife, and aquaculture. These environmental factors can reduce electricity generation efficiency and increase the risk of electrical faults, polymer insulation or jacketing degradation and hydrolysis of the PV cell encapsulant materials. Offshore PV modules may also be exposed to lower temperatures and buoyant and vibrating motions with a floating platform. It is not clear how the long-term performance of floating PV will be affected by these factors. To understand expected energy generation through solar cells on a floating platform, monitoring of the performance of PV modules in the marine environment is needed. This report outlines a plan for long-term testing of IRES PV components utilizing resources of the PNNL Material Aging and Detection (MAaD) Science team and the Marine and Coastal Research Laboratory (MCRL). Equipment applicable for onsite testing and real-time monitoring of the PV performance associated with environmental conditions including temperature, solar irradiance, shading and soiling is included. In case of performance loss, equipment for fault detection, failure analysis, material testing, and further troubleshooting are also available. Through establishment of this capabilities, the enabling IRES project sets the stage for future research to advance off-shore and near-shore energy options for businesses and communities.

14 SOLAR ENERGY↗
NASA NTRS2023

Lunar Dust Mitigation: A Guide and Reference: First Edition (2021)

On the surface of the Moon, lunar dust specifically presents unique challenges to operations long-term due to regolith particles’ ubiquitous presence in the lunar environment, potential to electrostatically charge and possible chemical reactivity. Whether to avoid exposure, try to remove or simply to tolerate lunar dust infiltrating a system becomes a complex question involving length of required service life, dust effects and critical risks, mass and complexity trades for the entire system. This publication provides a snapshot of advice from topical experts for specific areas of concern to systems targeted for deployment on the lunar surface. Following introductory overview commentary, dust mitigation approaches appropriate to the lunar surface are first addressed for typically static structures such as optical surfaces, radiators, and other thermal control surfaces, followed by regolith exposure concerns for communications equipment and non-optical sensors. The broad topic of mechanisms and mechanical assemblies is broken down to address relevant component level concerns, such as for bearings and for seals. “Soft goods” components of space suits (fabric) specific concerns are discussed, followed finally by brief coverage of human health issues and concerns, though the emphasis of this publication remains with components directly exposed to the harsh lunar surface environment. A description of some lunar surface hazard details, in particular characteristics of lunar surface dust, follows in Appendix A, and more detailed explanations of quantification issues for particulates are in Appendix B. The simple inertial removal of particles from a surface is discussed in Appendix C, followed by a summary of terrestrial best practices for dust mitigation recommended within select industries in Appendix D. The aggregated bibliography of references, while extensive and very useful, should not be construed to be exhaustive and can serve as a constructive start.

dust↗
DOE OSTI2026

Harnessing Ocean Thermal Gradients Using Thermoelectric Based Submersibles for Ocean Power Applications

The urgent need for energy solutions in marine environments has accelerated the development of innovative technologies capable of leveraging natural resources for power generation. This study introduces a buoyancy-driven submersible system designed to harness ocean thermal gradients using thermoelectric generators (TEGs) and phase change materials (PCMs). The technology aims to provide autonomous power to offshore aquaculture farms, unmanned underwater vehicles (UUVs), offshore platform illumination, and ocean sensors, significantly reducing dependence on fossil fuels. Ocean thermal gradients, especially prevalent in mid-latitude regions, exhibit temperature differences between surface and deep waters ranging from 7 degrees Celsius to 30 degrees Celsius depending on seasonal variations. The proposed submersible technology utilizes TEGs to convert thermal energy from these gradients into electrical power, generating between 0.2 and 0.5 watts, while PCMs are employed to store and regulate this energy, ensuring a stable and continuous power supply. The buoyancy-driven mechanism of the submersible enhances its capability to navigate through varying depths, optimizing its exposure to different thermal gradients and maximizing energy harvesting. The performance of this submersible system is analyzed through detailed thermodynamic assessments and computational fluid dynamics (CFD) modeling focused on heat transfer. These analyzes consider real-world ocean temperature profiles and seek to refine the interaction between TEGs and PCMs to optimize energy extraction. The evaluation encompasses several key performance metrics, including power output and energy efficiency. Results confirm the potential of this innovative technology to provide a continuous and reliable power source for marine applications. By demonstrating the feasibility of using ocean thermal gradients for energy generation, this study contributes to the broader efforts of innovation in energy technologies for harsh, remote marine environments. The implementation of such promises is significant advancements in the autonomy of marine operations. The ongoing research will further investigate scalability ensuring that the system can be effectively adapted to various marine settings and operational demands.

16 TIDAL AND WAVE POWER↗