This report is one in a series of Electrification Futures Study (EFS) publications. The EFS is a multiyear research project to explore potential widespread electrification in the future energy system of the United States. Electrification is defined as the substitution of electricity for direct combustion of non-electricity-based fuels used to provide similar services.

This report is the fourth publication in the EFS series, and it provides detailed descriptions of major methodological modifications to the power system model that can be used in future EFS studies, in order to better reflect key impacts of electrification. The levels of electrification underlying the changes needed to power sector modeling are derived from the second report (Mai et al. 2018), coupled with various assumptions about prominent drivers that influence the future generation mix on the bulk power system.