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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 379 records · Page 21
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Threefold reduction of modeled uncertainty in direct radiative effects over biomass burning regions by constraining absorbing aerosols

Absorbing aerosols emitted from biomass burning (BB) greatly affect the radiation balance, cloudiness, and circulation over tropical regions. Assessments of these impacts rely heavily on the modeled aerosol absorption from poorly constrained global models and thus exhibit large uncertainties. By combining the AeroCom model ensemble with satellite and in situ observations, we provide constraints on the aerosol absorption optical depth (AAOD) over the Amazon and Africa. Our approach enables identification of error contributions from emission, lifetime, and MAC (mass absorption coefficient) per model, with MAC and emission dominating the AAOD errors over Amazon and Africa, respectively. In addition to primary emissions, our analysis suggests substantial formation of secondary organic aerosols over the Amazon but not over Africa. Furthermore, we find that differences in direct aerosol radiative effects between models decrease by threefold over the BB source and outflow regions after correcting the identified errors. This highlights the potential to greatly reduce the uncertainty in the most uncertain radiative forcing agent.

09 BIOMASS FUELS↗
DOE OSTI2019

Understanding Adoption of a Key Soft Cost Reduction Strategy: Modeling Administrative Choices Regarding Streamlined Solar Permitting (Final Technical Report)

In the U.S., the process by which residential rooftop solar photovoltaic (PV) system installations are permitted and inspected by an “authority having jurisdiction” (AHJ) and interconnected to the grid varies across the country. As the U.S. has roughly 23,000 AHJs and 3,000 utilities with varying degrees of local autonomy, permitting, inspection, and interconnection (PI&I) heterogeneity represents a significant “soft cost” barrier to the growth of the residential solar PV market. Burkhardt et al. (2015), for example, finds that variations in local permitting procedures alone can lead to differences in average residential PV prices of approximately ${$}$0.14-${$}$0.18/W. When the authors considered jurisdictional variation in permitting plus regulatory procedures, that price differential grew to ${$}$0.64-${$}$0.93/W between the least-favorable and most-favorable jurisdictions. The objective of this project was to determine suites of PI&I reforms that fit the preferences of AHJs and utilities nationwide, as mediated through the preferences of PV installers, with the hoped-for impact of significantly improving the consistency of PI&I for solar PV across the U.S. To accomplish this objective, the project team set out to design and implement survey instruments with embedded discrete choice experiments (DCEs) that used individual PI&I reforms as attributes, with levels informed by a detailed understanding of the PI&I reforms. The analysis of the surveys was to include both defined and latent class analysis of the survey results, in order to identify different sets of AHJs and utilities that would prefer different “mass customized” SSP practice combinations. Note that this project would also have advanced the social science by applying well-established choice analysis techniques to the novel setting of public administration.

14 SOLAR ENERGY↗