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This report is one in a series of Electrification Futures Study (EFS) publications. The EFS is a multi-year research project to explore widespread electrification in the future energy system of the United States. This report documents a new model, the demand-side grid (dsgrid) model, which was developed for the EFS and in recognition of a general need for a more detailed understanding of electricity load. dsgrid utilizes a suite of bottom-up engineering models across all major economic sectors-transportation, residential and commercial buildings, and industry-to develop hourly electricity consumption profiles for every county in the contiguous United States (CONUS). The consumption profiles are available by subsector and end use as well as in aggregate. This report documents a bottom-up modeling assessment of historical ( 2012) consumption and explains the key inputs, methodology, assumptions, and limitations of dsgrid.The EFS is specifically designed to examine electric technology cost advancement and adoption for end uses across all major economic sectors as well as electricity consumption growth and load profiles, future power system infrastructure development and operations, and the economic and environmental implications of electrification. Because of the expansive scope and the multiyear duration of the study, research findings and supporting data will be published as a series of reports, with each report released on its own timeframe. Future research to be presented in future planned EFS publications will rely on dsgrid to analyze the hourly electricity consumption under scenarios with various levels of electrification. In addition to providing electricity consumption data for the planned EFS analysis, dsgrid can be used for other analysis outside the EFS research umbrella.More information and the supporting data associated with this report, links to other reports in the EFS study, and information about the broader study are available at www.nrel.gov/efs.

This paper discusses the techniques, challenges, and results of measuring computer power supply (CPS) efficiency, power factor (PF), and input harmonic currents for the 80 PLUS® program since its beginning in 2002. To date, over 750 power supplies have been tested with many certified for the 80 PLUS® program. In spite of the large number of power supplies tested and years of testing, there is uncertainty within the computer power supply industry about the correct method for measuring efficiency, power factor, and harmonics. Moreover, in order to improve efficiency at light loading, manufacturers are adopting a duty-cycle control approach to power factor correction that raises even more questions on the proper measurement techniques. This paper presents detailed results of years of computer power supply testing, provides a detailed technical analysis on measurement accuracy with background on why specific measurement techniques were adopted, and looks to the future on upcoming technical difficulties and offers solutions for overcoming these difficulties.

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