Proof Engine Verification: Renewable energy (solar + wind) can replace fossil fuels without major grid upgrades or backups.

Verdict: DISPROVED - **Both sub-claims disproved.** The IEA, IRENA, and EIA all explicitly state that grid upgrades and energy storage are essential for integrating high shares of solar and wind power. - **Grid investment must nearly double** — from ~$300B/year to over $600B/year by 2030 — just to keep pace with renewable deployment (B1). - **Energy storage is not optional.** 24 GW of battery storage is planned for 2026 in the U.S. alone (B6), and the IEA states flexibility needs will double by 2030 (B4). - **No c