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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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The use of a thermodynamically closed reactor prevented the interference of hot-charge carriers in the plasmonic-heat driven Claisen rearrangement, which is conventionally performed with electrical-heating at 250 °C.
A simple model incorporating linear radiation characteristics, along with the optical trains and geometrical concentration ratios of solar concentrators is presented with performance examples for optical trains of HCPV, LCPV and benchmark flat-plate PV.
A facility for testing different components for HCPV application has been developed in the framework of 'Fotovoltaico ad Alta Efficienza' (FAE) project funded by the Sicilian Regional Authority (PO FESR Sicilia 2007/2013 4.1.1.1). The testing facility is equipped with an heliostat providing a wide solar beam inside the lab, an optical bench for mounting and aligning the HCPV components, electronic equipments to characterize the I-V curves of multijunction cells operated up to 2000 suns, a system to circulate a fluid in the heat sink at controlled temperature and flow-rate, a data logging system with sensors to measure temperatures in several locations and fluid pressures at the inlet and outlet of the heat sink, and a climatic chamber with large test volume to test assembled HCPV modules.
As the effects of anthropogenic climate change become more severe, several approaches for deliberate climate intervention to reduce or stabilize Earth’s surface temperature have been proposed. Solar radiation modification (SRM) is one potential approach to partially counteract anthropogenic warming by reflecting a small proportion of the incoming solar radiation to increase Earth’s albedo. While climate science research has focused on the predicted climate effects of SRM, almost no studies have investigated the impacts that SRM would have on ecological systems. The impacts and risks posed by SRM would vary by implementation scenario, anthropogenic climate effects, geographic region, and by ecosystem, community, population, and organism. Complex interactions among Earth’s climate system and living systems would further affect SRM impacts and risks. We focus here on stratospheric aerosol intervention (SAI), a well-studied and relatively feasible SRM scheme that is likely to have a large impact on Earth’s surface temperature. We outline current gaps in knowledge about both helpful and harmful predicted effects of SAI on ecological systems. Desired ecological outcomes might also inform development of future SAI implementation scenarios. In addition to filling these knowledge gaps, increased collaboration between ecologists and climate scientists would identify a common set of SAI research goals and improve the communication about potential SAI impacts and risks with the public. Without this collaboration, forecasts of SAI impacts will overlook potential effects on biodiversity and ecosystem services for humanity.
This study examines how messaging approaches in a prosocial intervention can influence not only the effectiveness of the intervention but also, contagion afterward. Our investigation focuses on leveraging two motivations for solar adoption: self-interest and prosocial. Using data from a natural field experiment in 29 municipalities containing 684,000 people, we find that self-interest messaging is twice as effective in inducing solar adoption both during and after the intervention. Adoptions under self-interest messaging have 10% higher net present value, but prosocial messaging increases the likelihood that adopters recommend solar to their friends and neighbors. Income moderates the effectiveness of self-interest messaging, performing much better in high-income communities than low- and moderate-income communities. There was no significant difference across income groups for prosocial messaging. These results provide guidance to policy makers aiming to encourage prosocial behavior across all income groups.
Photovoltaic (PV) electricity generation has grown to about 17 GW in the United States, corresponding to one tenth of the global capacity. Most deployment in the country has happened during the last 6 years. Reflecting back in time, in early 2008 this author and his collaborators James Mason and Ken Zweibel, published in Scientific American and in Energy Policy a Solar Grand Plan demonstrating the feasibility of renewable energy in providing 69% of the U.S. electricity demand by 2050, while reducing CO2 emissions by 60% from 2005 levels; the PV contribution to this plan was assessed to be 250 GW by 2030, and 2,900 GW by 2050 [1]. The DOE’s more detailed SunShot vision study, released in 2012, showed the possibility of having 300 GW of PV installed in the United States by 2030, and 630 GW by 2050.
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A report on the discovery of the Bionic Leaf
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Pleotint, LLC was able to successfully extrude thermochromic interlayer for use in the fenestration industry. Pleotint has developed a thermochromic sytem that requires two thermochromic colors to make a neutral color when in the tinted state. These two colors were assembled into a single interlayer called a tri-layer prelam by Crown Operations for use in the glass lamination industry. Various locations, orientations, and constructions of thermochromic windows were studied with funds from this contract. Locations included Australia, California, Costa Rica, Indiana, Iowa, Mexico. Installed orientations included vertical and skylight glazing applications. Various constructions included monolithic, double pane, triple pane constructions. A daylighting study was conducted at LinEl Signature. LinEl Signature has a conference room with a sylight roof system that has a west orientation. The existing LinEl Signature conference room had constant tint 40% VLT transparent skylights. Irradiance meters were installed on the interior and exterior sides of a constant tint skylight. After a month and a half of data collection, the irradiance meters were removed and the constant tint skylights were replaced with Pleotint thermochromic skylight windows. The irradiance meters were reinstalled in the same locations and irradiance data was collected. Both data sets were compared. The data showed that there was a linear relationship with exterior and interior irradiance for the existing constant tint skylights. The thermochromic skylights have a non-linear relationship. The thermochromic skylights were able to limit the amount of irradiance that passed through the thermochromic skylight. A second study of the LinEl Signature conference was performed using EnergyPlus to calculate the amount of Illuminance that passed through constant tint skylights as compared to thermochromic skylights. The constant tint skylights transmitted Illuminance is 2.8 times higher than the thermochromic skylights during the months of May, June, July, August and 1.9 times higher than the thermochromic skylight during the months of March, April, September, October. Calculated illuminance levels were much more consistent as compared to the existing constant tint skylights installed at LinEl Signature. This allows for a more comfortable interior space in regard to glare discomfort and interior lighting control. Lawrence Berkeley National Laboratory was contracted to characterize the performance of the thermochromic interlayer and thermochromic window systems. Thermochromic interlayer was characterized with spectrometer equipment. The thermochromic window systems were characterized using LBNL’s Advanced Window Test Facility. A copy of the report can be found in the Appendix. Iowa State University was contracted to compare thermochromic window technology to constant tint technology. Iowa State University conducted the testing at the Energy Resource Station (ERS). The ERS has the ability to simultaneously test side-by-side competing building technologies. The building is equipped with two identical air handling units, each with its own dedicated and identical chiller. One air handling unit supplies the four test rooms designated as the A rooms and the other unit serves the four test rooms designated as the B rooms. There is one A test room and one B test rooms arranged as pairs in a side-by-side design with each pair having a different exposure. There is a pair of test rooms that face the south, an east and west facing pair. Each of the test rooms is a mirror image of its match with identical construction. The rooms are unoccupied; however, the capability to impose false loads on the rooms exists. The false loads and room lighting can be scheduled to simulate various usage patterns. A copy of the report can be found in the Appendix. GARD Analytics was contracted to compare EnergyPlus building simulations to the data recorded at the Iowa ERS. The goal of this research was to validate the building simulation software developed by the US Department of Energy. EnergyPlus is a whole building software package that includes thermochromic window system algorithms. The accuracy of these thermochromic window system algorithms were of special interest for this research.
The goal of this project was to demonstrate time resolved analysis of the electronic structure dynamic using techniques of miniature X-ray emission spectrometers. The focus was on development of easy/fast to set up, portable, cost efficient, good energy resolution, good sensitivity, dispersive (particularly suitable for time resolved analysis) system. These mile stones were achieved and miniXES spectrometer for the Mn Kβ range was reported. Contrary to pointby- point detection, the miniXES setup allows a complete emission spectrum to be recorded following each laser excitation, Fig. 1. miniXES system compares favorably with other realization of a dispersive XES spectrometer with cylindrically bent analyzers. Setup reported by others has disadvantages of high cost (which limits its re-creation by other researchers) and lower (0.55 eV) energy resolution (at 6490 eV). The energy resolution of our miniXES system is 0.30 eV. Additional advantage of portability allowed us to use miniXES at multiple beamlines at APS (ANL): 20-ID, 14-ID and 7-ID. Moreover, in March 2013 PI transported the Mn Kβ spectrometer (which fits into a small hand luggage bag) to SLS (Switzerland) and set it up there for the TR-XES beamtime. Our spectrometer works with 2D-PSD (Pilatus-100) which is a standard detector available via equipment pool at synchrotron sources.
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Abstract. The mean altitude of the smoke loading over the southeast Atlantic moves from the boundary layer in July to the free troposphere by October. This study details the month-by-month changes in cloud properties and the large-scale environment as a function of the biomass burning aerosol loading at Ascension Island (8∘ S, 14.5∘ W) from July to October, based on island measurements, satellite retrievals, and reanalysis. In July and August, the smoke loading predominantly varies within the boundary layer. During both months, the low-cloud fraction is less and is increasingly cumuliform when more smoke is present, with the exception of a late morning boundary layer deepening that encourages a short-lived cloud development. The meteorology varies little, suggesting aerosol–cloud interactions explain the cloudiness changes. September marks a transition month during which midlatitude disturbances can intrude into the Atlantic subtropics, constraining the free tropospheric aerosol closer to the African coast. Stronger boundary layer winds on cleaner days help deepen, dry, and cool much of the marine boundary layer compared to that on days with high smoke loadings, with stratocumulus reducing everywhere but at the northern deck edge. The September free troposphere is better mixed on smoky days compared to October. Longwave cooling rates, generated by a sharp water vapor gradient at the aerosol layer top, encourage a small-scale vertical mixing that could help maintain the well-mixed smoky September free troposphere. The October meteorology primarily varies as a function of the strength of the free tropospheric winds advecting aerosol offshore. The free tropospheric aerosol loading is less than in September, and the moisture variability is greater. Low-level clouds increase and are more stratiform in October when the smoke loadings are higher. The increased free tropospheric moisture can help sustain the clouds through a reduction in evaporative drying during cloud-top entrainment. Enhanced subsidence above the coastal upwelling region, increasing cloud droplet number concentrations, may further prolong cloud lifetime through microphysical interactions. Reduced subsidence underneath stronger free tropospheric winds at Ascension Island supports slightly higher cloud tops during smokier conditions. Overall, the monthly changes in the large-scale aerosol and moisture vertical structure act to amplify the seasonal cycle in low-cloud amount and morphology. This is climatically important, as cloudiness changes dominate changes in the top-of-atmosphere radiation budget.
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Earth reflected solar radiation and stability of satellite thermal control coatings, noting intensity distribution shifting toward UV region and coatings degradation rate
Solar radiation pressure acceleration effects on flat satellite in earth synchronous orbit, examining orbital shift and counteracting thrust velocity applications