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High-temperature receivers are critical for third-generation (Gen3) Concentrating Solar Power (CSP) technology to achieve high system efficiencies, and play the role of converting concentrated sunlight into heat. In this paper, two CSP systems with different working fluids in the receiver are examined in order to achieve identical supply of heat to the power block: a direct high-temperature chloride salt system and an indirect high-temperature sodium receiver with an associated heat exchanger to heat the same chloride salt. The presented numerical model indicates that the indirect sodium-salt system has a 4.37% higher exergy efficiency than the direct chloride salt system. The exergy destruction in the added sodium-salt heat exchanger was only 0.54%, which did not outweigh the performance benefits gained from using a sodium receiver, when compared to the direct salt case with no heat exchanger. Even at lower DNIs, the better heat-transfer characteristics of the sodium are responsible for its improved performance compared to salt in the receivers., QC 20220914Part of proceedings: ISBN 978-073544195-8

Bio‐logging data obtained by tagging animals are key to addressing global conservation challenges. However, the many thousands of existing bio‐logging datasets are not easily discoverable, universally comparable, nor readily accessible through existing repositories and across platforms, slowing down ecological research and effective management. A set of universal standards is needed to ensure discoverability, interoperability and effective translation of bio‐logging data into research and management recommendations. We propose a standardisation framework adhering to existing data principles (FAIR: Findable, Accessible, Interoperable and Reusable; and TRUST: Transparency, Responsibility, User focus, Sustainability and Technology) and involving the use of simple templates to create a data flow from manufacturers and researchers to compliant repositories, where automated procedures should be in place to prepare data availability into four standardised levels: (a) decoded raw data, (b) curated data, (c) interpolated data and (d) gridded data. Our framework allows for integration of simple tabular arrays (e.g. csv files) and creation of sharable and interoperable network Common Data Form (netCDF) files containing all the needed information for accuracy‐of‐use, rightful attribution (ensuring data providers keep ownership through the entire process) and data preservation security. We show the standardisation benefits for all stakeholders involved, and illustrate the application of our framework by focusing on marine animals and by providing examples of the workflow across all data levels, including filled templates and code to process data between levels, as well as templates to prepare netCDF files ready for sharing. Adoption of our framework will facilitate collection of Essential Ocean Variables (EOVs) in support of the Global Ocean Observing System (GOOS) and inter‐governmental assessments (e.g. the World Ocean Assessment), and will provide a starting point for broader

We perform optical analyses on multi-Aperture solar central receiver systems with compound parabolic concentrators to increase the power level for better economics., QC 20210323

A multi-aperture solar central receiver system is optically analyzed for increasing the net power to the receiver in a wide temperature range of 600-1800 K. A model system comprises a tower, a multi-aperture receiver with compound parabolic concentrators, and heliostat sub-fields. Optical modeling is performed using in-house developed Monte-Carlo ray-tracing programs. The heliostat sub-field geometrical configuration, the number of receiver apertures and optical properties of reflective surfaces are varied in the parametric study. Increasing the number of apertures from one to four increases the maximum net receiver power from 116MW to 332MW. The use of more than four apertures results in only limited further gain of the net receiver power but significantly decreases the overall optical efficiency and the solar-to-thermal efficiency. The optimal temperature for the maximized annual solar-to-exergy efficiency is found in the range of 1100-1200 K. This optimal temperature decreases slightly with an increasing number of apertures., QC 20210311

We present a new prospective analysis of deep multi-band imaging with the James Webb Space Telescope (JWST). In this work, we investigate the recovery of high-redshift 5 > z > 12 galaxies through extensive image simulations of accepted JWST programs, including the Early Release Science in the EGS field and the Guaranteed Time Observations in the HUDF. We introduced complete samples of ∼300 000 galaxies with stellar masses of log(M∗/M⊙)> 6 and redshifts of 0 < z< 15, as well as galactic stars, into realistic mock NIRCam, MIRI, and HST images to properly describe the impact of source blending. We extracted the photometry of the detected sources, as in real images, and estimated the physical properties of galaxies through spectral energy distribution fitting. We find that the photometric redshifts are primarily limited by the availability of blue-band and nearinfrared medium-band imaging. The stellar masses and star formation rates are recovered within 0.25 and 0.3 dex, respectively, for galaxies with accurate photometric redshifts. Brown dwarfs contaminating the z > 5 galaxy samples can be reduced to >0:01 arcmin-2 with a limited impact on galaxy completeness.We investigate multiple high-redshift galaxy selection techniques and find that the best compromise between completeness and purity at 5 < z < 10 using the full redshift posterior probability distributions. In the EGS field, the galaxy completeness remains higher than 50% at magnitudes mUV < 27:5 and at all redshifts, and the purity is maintained above 80 and 60% at z ≥ 7 and 10, respectively. The faint-end slope of the galaxy UV luminosity function is recovered with a precision of 0.1-0.25, and the cosmic star formation rate density within 0.1 dex. We argue in favor of additional observing programs covering larger areas to better constrain the bright end.