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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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At least 667 records · Page 37

Lessons Learned from Three Agrivoltaic Installations in New Jersey

Agrivoltaics is a new technology that has the potential to positively impact commercial farming by combining agricultural practices with the generation of solar energy. While some yield reduction is to be expected, resulting from less sunlight reaching the plant canopy and ground occupied by support structures, the generated electricity provides a low-risk supplemental income to farmers. In order to combine farming with electricity generation, agrivoltaic systems use a lower ground coverage ratio compared to normal solar farms and the PV panels are often mounted higher above the ground in order to facilitate the movement of agricultural equipment and to reduce the contrast between shaded and non-shaded areas. With funding provided from the state of New Jersey and the New Jersey Agricultural Experiment Station (NJAES), we designed and installed three unique agrivoltaic research systems at Rutgers/NJAES farms. These projects were recently completed and are generating electricity that is exported to the grid. This paper discusses the lessons we have learned along the way, including all the steps necessary to see an agrivoltaic project through to completion.

Both, A. J. (ORCID:0000000150845296)↗

Integration of Concentrating Solar Power with High Temperature Electrolysis for Hydrogen Production: Preprint

Hydrogen (H2) has been identified as a leading sustainable contender to replace fossil fuels in transportation and electricity generation. H2 production can be achieved by concentrating solar thermal power (CSP) systems collecting thermal energy from the sun to various chemical processes for fuel production. Fuel production via solar thermal chemical processes integrated with CSP uses the full spectrum of sunlight compared with photovoltaic power conversion and stores solar energy directly and efficiently [1]. The solar fuel production can be realized by thermochemical processes (e.g., water splitting for H2 production, carbon dioxide reduction, or methane reforming) or thermal electrochemical methods (e.g., integration with solid oxide electrolysis cell). Technology development for CSP-integrated solar fuel production requires broad technological bases from solar energy collection to chemical energy conversion. H2 generated from renewable sources can be an energy carrier for a carbon-free economy. Integrating CSP with high temperature electrolysis (HTE) using solid oxide electrolysis cells (SOEC) provides a renewable path for H2 generation. The CSP-HTE integration approach provides the benefit of thermal energy storage (TES) for continuous operation, improved capacity, and SOEC life. H2 gas has low energy density for transportation, pipeline networks are expensive, and H2 liquefaction is energy intensive. However, an alternative method for H2 distribution is to use carbon dioxide (CO2) capture and liquid hydrocarbon synthesis to convert solar energy into liquid fuels that are compatible with the existing fossil fuel infrastructure.

concentrating solar thermal power↗

PERFORMANCE OF SPECTRALLY SELECTIVE COLLECTOR SURFACES IN A SOLAR-DRIVEN CARNOT SPACE-POWER SYSTEM

A study was made of the theoretical performance of spectrally selective surfaces when used as the collectors of solar energy for driving heat engine cycles in space. Selective surfaces were considered for which the-monochromatic emissivity changed abruptly at specific wavelengths between 0.5 and 10 microns. The Carnot cycle was used as the heat engine, and waste heat was rejected from a black radiator. Systems using both focused and unfocused radiation were considered. It was found that spectrally selective surfaces hold considerable promise as collectors of solar energy in unfocused systems. The efficiency for these is several times greater than that obtainable from black or gray collectors. However, this advantage of spectral selectivity diminishes if the sunlight is focused on the collector. In highly focused systems, such as those using parabolic mirrors, black collectors give substantially the same efficiency as the most ideal spectrally selective surface.

SOLAR PROPULSION↗

Special coatings control temperature of structures

Special coatings in the form of paints that exhibit controlled ratios of sunlight absorptivity to grey-body emissivity control the temperature of structures in space flight. These finishes exhibit good resistance to ultraviolet radiation and do not discolor.

Fulk, M. M.↗

Hydrogen Fire Detection System Features Sharp Discrimination

Hydrogen fire detection system discovers fires by detecting the flickering ultraviolet radiation emitted by the OH molecule, a short-lived intermediate combustion product found in hydrogen-air flames. In a space application, the system discriminates against false signals from sunlight and rocket engine exhaust plume radiation.

Bright, C. S.↗

The atmosphere of Mars.

Mars atmosphere surface pressure, radiative equilibrium temperatures, sunlight resonance scattering distribution, etc

SURFACE PRESSURE↗