Our benchmarking method includes bottom-up accounting for all necessary system and project-development costs incurred when installing residential, commercial, and utility-scale systems, and it models the Q1 2021 costs for such systems, excluding any previous supply agreements. . Our benchmarking method includes bottom-up accounting for all necessary system and project-development costs incurred when installing residential, commercial, and utility-scale systems, and it models the Q1 2021 costs for such systems, excluding any previous supply agreements. . Each year, the U. Department of Energy (DOE) Solar Energy Technologies Office (SETO) and its national laboratory partners analyze cost data for U. solar photovoltaic (PV) systems to develop cost benchmarks. These benchmarks help measure progress toward goals for reducing solar electricity costs. . The National Renewable Energy Laboratory (NREL) publishes benchmark reports that disaggregate photovoltaic (PV) and energy storage (battery) system installation costs to inform SETO's R&D investment decisions. This year, we introduce a new PV and storage cost modeling approach. Our analysis targets: Think of an energy storage cabinet as a tech-savvy Russian. .