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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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NASA NTRS2020

Satellite Beach Energy - Restructuring the Energy Balance in Satellite Beach, Florida, by Quantifying Solar Energy Production Potential using NASA POWER Data Products and LiDAR

The City of Satellite Beach, Florida, has committed to supplying 100% of its energy use from renewable energy, primarily solar, by the year 2050. The team created a methodology for estimating rooftop solar power potential using a high-resolution Light Detection and Ranging (LiDAR) dataset and the NASA Prediction of Worldwide Energy Resources (POWER) dataset to assist Satellite Beach in reaching their solar renewable energy goals. The POWER dataset provides information on direct and diffuse solar irradiation on horizontal surfaces, surface albedo, and effects of local meteorology, such as clouds. The team integrated the solar irradiance data with the LiDAR data to model slope, aspect, and shadowing in the 7 km2 study area to find suitable roof segments for solar panel installation and estimate the solar potential of each segment. This process was supplemented by an analysis of land surface temperature and urban greenness measured through the Normalized Difference Vegetation Index (NDVI) from Landsat 8 Operational Land Imager and Thermal Infrared Sensor (OLI/TIRS) observations. These metrics serve to target areas for cooling initiatives aimed at reducing Satellite Beach’s overall energy consumption. The team found the total rooftop solar potential throughout the city to be 221,919,330KWh per year with an average annual rooftop photovoltaic, or PV, potential of 55,647KWh per building. As such, the average building could generate over five times the annual energy needs for an average household if PV panels were installed on all viable areas of its roof.

Spencer Nelson↗

NASA NTRS1991

Requirements of a solar diffuser and measurements of some candidate materials

If the solar spectral irradiance and the orientation and directional reflectance of a solar diffuser are known, then the spectral radiance of the diffuser is readily calculated and it can be used for the accurate absolute calibration of a satellite sensor. However, the solar diffuser is exposed during in-flight satellite sensor calibration to high-energy ultraviolet irradiance, particle impacts and atomic oxygen effects. This paper describes desirable solar diffuser characteristics and the results of proton and UV irradiation on the directional-hemispheric spectral reflectance, the bidirectional spectral reflectance factor and the polarization properties of candidate diffuser materials.

Guzman, Carmen T.↗

DOE OSTI2024

A Refined Method to Translate Solar Data Quality Assessment Flags to Estimated Measurement Uncertainty

Integrating solar resource uncertainties due to radiometer measurement performance and operational data quality assessment can provide improved estimates of economic bankability, system design performance, and compliance of solar energy conversion systems. Estimating radiometer measurement uncertainty is an established procedure consistent with recognized best practices and international guidelines. SERI QC is a robust solar data quality assessment software tool that has been in continuous use for more than three decades. This report, the fourth of six for the Data Quality and Uncertainty Integration Project, presents a refined algorithm description for software to translate solar resource data quality assessment results into estimated uncertainty values in a Solar Resource Operational Uncertainty Integrator (SROUI) application. This algorithm requires three-component solar irradiance measurements - global horizontal irradiance, direct normal irradiance, and diffuse horizontal irradiance - collected at 1- to 60-minute intervals, as described in the previous deliverables. The development of this report as Deliverable 6.4 was an iterative process that included reviews and feedback from the project team on initial drafts designed to refine how the new software could best support determining solar resource data uncertainty. The results of this effort will contribute to the final software system development by National Renewable Energy Laboratory staff.

14 SOLAR ENERGY↗

NASA NTRS1994

Improvement of the photometric sunspot index and changes of the disk-integrated sunspot contrast with time

The photometric sunspot index (PSI) was developed to study the effects of sunspots on solar irradiance. It is calculated from the sunspot data published in the Solar-Geophysical Data catalog. It has been shown that the former PSI models overestimate the effect of dark sunspots on solar irradiance; furthermore results of direct sunspot photometry indicate that the contrast of spots depends on their area. An improved PSI calculation is presented; it takes into account the area dependence of the contrast and calculates `true' daily means for each observation using the differential rotation of the spots. Moreover, the observations are screened for outliers which improves the homogeneity of the data set substantially, at least for the period after December 1981 when NOAA started to report data from a few instead of one to two stations. A detailed description of the method is provided. The correlation between the newly calculated PSI and total solar irradiance is studied for different phases of the solar cycles 21 and 22 using bi-variate spectral analysis. The results can be used as a `calibration' of PSI in terms of gain, the factor by which PSI has to be multiplied to yield the observed irradiance change. The factor changes with time from about 0.6 in 1980 to 1.1 in 1990. This unexpected result cannot be interpreted by a change of the contrast relative to the quiet Sun (as it is normally defined and determined by direct photometry) but rather as a change of the contrast between the spots and their surrounding as seen in total irradiance (integrated over the solar disk). This may partly be explained by a change in the ratio between the areas of the spots and the surrounding faculae.

Froehlich, Claus↗

DOE OSTI2023

Integration of a physics-based direct normal irradiance (DNI) model to enhance the National Solar Radiation Database (NSRDB)

Explore the source record for details and available documents.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS2002

Comparing Sunspot Area and Sunspot Number as Proxies for Long-term Solar Irradiance Variation

Because relevant observations from space began only in 1979 with Nimbus-7, it is impossible to correlate direct measurements of small changes in solar irradiance with terrestrial temperature over a number of solar cycles. Yet there is recent evidence that some feature of solar change over a cycle may have a larger influence on climate than would result from merely introducing the additional amount of heat delivered to Earth's atmosphere at solar minimum. It would be useful to check this possibility over several solar cycles. To do this, we would need a sufficiently reliable proxy for irradiance change that at least survives a test against the space observations. Sunspot area is a fairly straightforward parameter to measure, and is associated with the extent of magnetic activity known to correlate strongly with solar irradiance change. We have tested the use of sunspot area as a long-term proxy for solar irradiance change, using observations made at the Coimbra Solar Observatory, from which we obtain both statistically weighted sunspot numbers and sunspot areas over the period 1980-1992. These are both correlated with solar irradiance values measured from Nimbus-7 spacecraft over the same time period, to see if sunspot area offers affords a strong positive correlation and also a distinct advantage over sunspot number as a useful proxy that can then be compared with terrestrial temperature records. Preliminary results yield a positive correlation of 0.71 for sunspot area, but further tests are being conducted and will be reported.

Jordan, Stuart D.↗

NASA NTRS1985

Active Cavity Radiometer (ACR)

The active cavity radiometer (ACR) measures the total solar irradiance to determine the magnitude and direction of variations in the total solar radiative output. The ACR is an electrically self calibrating cavity pyroheliometer capable of measuring the total solar irradiance with an absolute accuracy better than 0.2% and capable of detecting changes in the total irradiance smaller than 0.001%. The data will be used to study the physical behavior of the Sun and the Earth's climate.

Moore, R. L.↗

NASA NTRS1986

Active Cavity Radiometer (ACR)

Moore, R.↗

NASA NTRS1990

Irradiance Variability of the Sun

Direct measurements of the solar constant--the total irradiance at mean Sun-Earth distance--during the last ten years from satellites show variations over time scales from minutes to years and decades. At high frequencies the spectral power is determined by granulation, super- and mesogranulation. In the 5-minute range, moreover, it is dominated by power from the solar p-mode oscillations. Their power and frequencies change with time, yielding information about changes in the convection zone. During periods of several hours, the power is steadily increasing and may be partly due to solar gravity modes. The most important variance is in the range from days to several months and is related to the photospheric features of solar activity, decrease of the irradiance during the appearance of sunspots, and increasing by faculae and the magnetic network. Long-term modulation by the 11-year activity cycle are observed conclusively with the irradiance being higher during solar maximum. All these variations can be explained--at least qualitatively--by their manifestation on the photosphere. For the long-term changes, the simultaneous changes of the frequencies of solar p-mode oscillations suggest a more global origin of the variations. Indeed, it seems that the observed irradiance modulation is a true luminosity change with the magnetic cycle of the Sun.

Froehlich, Claus↗

NASA NTRS2015

Total and Spectral Solar Irradiance Sensor (TSIS) Project Overview

The main objective of the Total and Spectral solar Irradiance Sensor (TSIS) is to acquire measurements to determine the direct and indirect effects of solar radiation on climate. TSIS total solar irradiance measurements will extend a 37-year long uninterrupted measurement record of incoming solar radiation, the dominant energy source driving the Earths climate and the most precise indicator of changes in the Suns energy output. TSIS solar spectral irradiance measurements will determine the regions of the Earths multi-layered atmosphere that are affected by solar variability, from which the solar forcing mechanisms causing changes in climate can be quantified. TSIS includes two instruments: the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM), integrated into a single payload. The TSIS TIM and SIM instruments are upgraded versions of the two instruments that are flying on the Solar Radiation and Climate Experiment (SORCE) mission launched in January 2003. TSIS was originally planned for the nadir-pointing National Polar-orbiting Operational Environmental Satellite System (NPOESS) spacecraft. The TSIS instrument passed a Critical Design Review (CDR) for NPOESS in December 2009. In 2010, TSIS was re-planned for the Joint Polar Satellite System (JPSS) Polar Free Flyer (PFF). The TSIS TIM, SIM, and associated electronics were built, tested, and successfully completed pre-ship review as of December 2013.In early 2014, NOAA and NASA agreed to fly TSIS on the International Space Station (ISS). In the FY16 Presidents Budget, NASA assumes responsibility for the TSIS mission on ISS. The TSIS project includes requirements, interface, design, build and test of the TSIS payload, including an updated pointing system, for accommodation on the ISS. It takes advantage of the prior development of the TSIS sensors and electronics. The International Space Station (ISS) program contributions include launch services and robotic installation of the TSIS payload onto an ISS Express Logistics Carrier, mission operations, and communications. Total and Spectral solar irradiance data products will be produced, calibrated, and made publically available through the Goddard Earth Science Data and Information Services Center (GES DISC).The NASA GSFC TSIS project at GSFC is responsible for project management, system engineering, safety and mission assurance, and engineering oversight for the TSIS payload. The TSIS project has contracted with the University of Colorado Laboratory for Atmospheric and Space Physics (LASP) for the design, development and testing of TSIS, support for ISS integration, science operations of the TSIS instrument, data processing, data evaluation and delivery to the GES DISC. TSIS will be delivered to Kennedy Space Center for integration in 2017, with launch and installation onto ISS planned for late 2017-early 2018. After a 90-day check-out period, NASA plans five years of TSIS operations.

spectral emission↗

DOE OSTI2025

Bio‐Inspired Cascade Photocatalysis on Fe Single‐Atom Carbon Nitride Upcycles Plastic Wastes for Effective Acetic Acid Production

Plastic imposes a critical threat to the environment, ecosystems, and human health because of the low utilization efficiency of plastics. Here, we demonstrate a sustainable, highly efficient cascade photocatalysis for upcycle plastics to value-added acetic acid using Fe single-atom catalysts (Fe@C 3 N 4 SAC) at ambient conditions. Inspired by Phanerochaete chrysosporium microbial, the defective Fe@C 3 N 4 SAC acts as a bifunctional cascade photocatalyst for both Fenton-like and CO 2 reduction reactions. During the reaction, hydroxyl radicals (*OH) form and subsequently oxidize plastics into CO 2 intermediates. These CO 2 intermediates are then photo-reduced to CH 3 COOH on the same catalyst via cascade photocatalysis. The mechanism is confirmed by in situ multimodal microscopy and spectroscopies, with density functional theory calculations. A state-of-art CH 3 COOH yield of 63.8 mg h −1 gcat −1 from PVC, 12.7 mg h −1 gcat −1 from PE, 5.4 mg h −1 gcat −1 from PET, and 5.3 mg h −1 gcat −1 from PP are directly obtained under AM1.5G solar irradiation and further validated under real sunlight (≈0.6 sun), achieving 5.6 mg h −1 gcat −1 from PET, using low-cost Fe@C 3 N 4 SAC in a sealed reactor by enhancing the photon transport and utilization efficiency. The techno-economic analysis shows it is promising to practically mitigate plastic based on broader social welfare assessments.

cascade photocatalysis↗

NASA NTRS1993

Scientific studies in association with the Shuttle Solar Backscatter Ultraviolet (SSBUV) project

During the past reporting period efforts focused on performing detailed comparisons between measurements made by the SBUV/2 V instruments carried on NOAA-9 and NOAA-11 and the first three flights of the Shuttle Solar Backscatter Ultraviolet (SSBUV) project. The quantities to be compared are the measurables, being the ratio of emergent radiance (I) in the vertical direction to the incoming solar irradiance (F). The backscatter albedo, A(w,j), was defined by: A(w,j) = I(w,j)/F(w,j) where w = 1,2,..., 12 refers to wavelength, and j indicates the instrument and flight on which the data were obtained. The comparisons to be made are NOAA-9 to SSBUV-1, NOAA-11 to SSBUV-2, and NOAA-11 to SSBUV-3. For the comparisons the N-values contained in the data files supplied by GSFC were converted to albedos via: A(w,j) = 10(exp N(w,j)/100). The comparisons described were designed to characterize the differences between the NOAA and SSBUV data sets.

Frederick, John E.↗

DOE OSTI2022

A Physics-Based DNI Model for Advancing Solar Resource Assessment and Forecasting: Preprint

Direct Normal Irradiance (DNI) is one of the most used quantities to quantify the magnitude of solar energy resource. The concept of DNI is often interpreted differently for ground measurements and solar forecasting by numerical weather prediction (NWP) models, leading to substantial bias during evaluation of DNI forecasts especially under cloudy-sky conditions. To eliminate the bias, we use the Fast All-sky Radiation Model for Solar applications with DNI (FARMS-DNI) to provide a physics-based solution of solar radiation in the circumsolar region. The FARMS-DNI is implemented in the Weather Research and Forecasting model with solar extensions (WRF-Solar) to forecast day-ahead DNI in the north America. By comparing with conventional predictions from WRF-Solar and satellite observations from the National Solar Radiation Data Base (NSRDB), we found significant improvements in our prediction of DNI.

DNI↗

NASA NTRS1996

Total Solar Irradiance Variability: A Review

Observations of total solar irradiance from space within the last two decaades convinced the skeptics that total irradiance varies over a wide range of periodicities: from minutes to the 11-year solar activity cycle. Analyses based on these space-borne observations have demonstrated that the irradiance variations are directly related to changes at the photosphere and the solar interior.

solar irradiance solar luminosity irradiance model↗

NASA NTRS2003

Computation of Domain-Averaged Shortwave Irradiance by a One-Dimensional Algorithm Incorporating Correlations between Optical Thickness and Direct Incident Radiation

A one-dimensional radiative transfer algorithm that accounts for correlations between the optical thickness and the incident direct solar radiation is developed to compute the domain-averaged shortwave irradiance profile. It divides the direct irradiance into four components and treats the direct irradiance in two separate, clear and cloudy columns to account for the fact that clouds attenuate the direct irradiance more than clear-sky. The horizontal inhomogeneity of clouds in the cloudy column is treated by the gamma weighted two-stream approximation, which assumes that the optical thickness of clouds follows a gamma distribution. The algorithm inputs the cloud fraction, cumulative cloud fraction as a function of height, and a parameter expressing the shape of the probability density function of the cloud optical thickness distribution in addition to inputs required for a two-stream radiative transfer model. These cloud property inputs can be obtained using ground- and satellite-based instruments. Therefore, the algorithm can treat realistic cloud overlap features and horizontal inhomogeneity of clouds in a framework of one- dimensional radiative transfer. Heating rates computed by the algorithm using cloud fields generated by cloud resolving models agree with those computed with a Monte Carlo model. If optical properties in computational layers that divide a vertically extensive cloud are correlated, the irradiance profile computed by the algorithm further improves.

Kato, S.↗

DOE OSTI2024

Photocatalytic Semi‐Hydrogenation of Acetylene to Polymer‐Grade Ethylene with Molecular and Metal–Organic Framework Cobaloximes

Abstract The semi‐hydrogenation of acetylene in ethylene‐rich gas streams is a high‐priority industrial chemical reaction for producing polymer‐grade ethylene. Traditional thermocatalytic routes for acetylene reduction to ethylene, despite progress, still require high temperatures and high H 2 consumption, possess relatively low selectivity, and use a noble metal catalyst. Light‐powered strategies are starting to emerge, given that they have the potential to use directly the abundant and sustainable solar irradiation, but are ineffective. Here an efficient, >99.9% selective, visible‐light powered, catalytic conversion of acetylene to ethylene is reported. The catalyst is a homogeneous molecular cobaloxime that operates in tandem with a photosensitizer at room temperature and bypasses the use of non‐environmentally friendly and flammable H 2 gas feed. The reaction proceeds through a cobalt‐hydride intermediate with ≈100% conversion of acetylene under competitive (ethylene co‐feed) conditions after only 50 min, and with no evolution of H 2 or over‐hydrogenation to ethane. The cobaloxime is further incorporated as a linker in a metal–organic framework; the result is a heterogeneous catalyst for the conversion of acetylene under competitive (ethylene co‐feed) conditions that can be recycled up to six times and remains catalytically active for 48 h, before significant loss of performance is observed.

Stone, Aaron E. B. S.↗

NASA NTRS1985

Solar-induced oscillations in the stratosphere - A myth or reality?

Chandra (1984) has provided an assessment of the solar cycle ozone relationship based on seven years of Nimbus 4 BUV (backscattered ultraviolet) data. It was found that the globally averaged ozone in the upper stratosphere, when corrected for the changes in instrument sensitivity, decreased from 1970 to 1976 by 3-4 percent. This decrease is in accordance with the current estimates of solar UV variability over a solar cycle. The present investigation has the objective to determine if measured changes in ozone and temperature in the upper stratosphere on a time scale of a solar rotation are of solar origin, i.e., directly induced by changes in solar irradiance. The conducted study is based on the first two years (1970-1972) of ozone and temperature data obtained from the Nimbus 4 BUV and the Selective Chopper Radiometer (SCR) experiments. Attention is given to the response of the stratosphere to changes in solar activity associated with the 27-day solar rotation.

Chandra, S.↗

NASA NTRS2002

Behavioral consequences of radiation exposure to simulated space radiation in the C57BL/6 mouse: open field, rotorod, and acoustic startle

Two experiments were carried out to investigate the consequences of exposure to proton radiation, such as might occur for astronauts during space flight. C57BL/6 mice were exposed, either with or without 15-g/cm2 aluminum shielding, to 0-, 3-, or 4-Gy proton irradiation mimicking features of a solar particle event. Irradiation produced transient direct deficits in open-field exploratory behavior and acoustic startle habituation. Rotorod performance at 18 rpm was impaired by exposure to proton radiation and was impaired at 26 rpm, but only for mice irradiated with shielding and at the 4-Gy dose. Long-term (>2 weeks) indirect deficits in open-field activity appeared as a result of impaired experiential encoding immediately following exposure. A 2-week recovery prior to testing decreased most of the direct effects of exposure, with only rotorod performance at 26 rpm being impaired. These results suggest that the performance deficits may have been mediated by radiation damage to hippocampal, cerebellar, and possibly, forebrain dopaminergic function.

Non-NASA Center↗