Green hydrogen production breakthrough uses steel slag and coal ash to cut costs and capture CO2

Most core claims match a 2026 Ohio State University study and press release on converting steel slag and coal ash with CO₂ to make calcite and lower-voltage electrolysis producing potentially sub‑$1/kg, net‑negative hydrogen. Some specific numbers (slag/ash tonnages, 500 Mt CO₂ potential) are only loosely supported or appear extrapolated and should be softened or explicitly labeled as estimates or illustrative scenarios.