A modern 2026 Tier 1 residential solar panel weighs 41–62 lbs (18. 7 lbs per square foot (12–13 kg/m²). A complete rooftop array — panels plus aluminum rails plus brackets plus wiring — adds about 3–4 psf of distributed dead load.
5 million, depending on three key factors: Battery Chemistry: Lithium-ion dominates, but newcomers like lithium-sulfur promise 3x the storage at lower costs. Toyota Prius of batteries—both work, but one's. Prices swing between $1.