Why China's Supercritical CO₂ Turbine Matters

TL;DR

China's first commercial sCO2 generator claims 85% efficiency gains over steam, potentially transforming how existing power plants generate electricity.

Key Points

• 1.Supercritical CO₂ exists in a unique phase between liquid and gas. Above 31°C and 7.39 MPa pressure, CO₂ becomes denser than steam, allowing smaller turbines to generate more power using the Brayton cycle, which theoretically hits 50%+ efficiency versus steam's 33% Rankine cycle.
• 2.China's Chaotan One is the world's first commercial sCO2 generator, launched December 20, 2025. Built at a Shougang Shuicheng steel plant in Guizhou Province, it runs on waste heat and claims an 85% efficiency increase and 50% more power output from the same facility.
• 3.The 17-year Chinese development program overcame major technological barriers. After being refused access to precision vacuum-welding technology four times, Huang Yanping's team spent 829 days developing their own process, testing 218 parameters across 49 process tests before a breakthrough in winter 2021.
• 4.The US has pursued sCO2 longer but more cautiously than China. Sandia National Labs has worked on it since the late 2000s, first delivered 10 kW to the grid in April 2022, reached 4 MW with the STEP Demo project in October 2024, and targets commercial designs by the mid-2030s.
• 5.Long-term durability is the critical unresolved question. Analysts estimate a 40–70% probability of measurable performance degradation within 2–5 years due to near-impossible-to-repair heat exchangers, sCO2 seal leaks, corrosion from contaminants, and industrial exhaust buildup reducing efficiency over time.
• 6.The most transformative application may be retrofitting existing plants and powering AI data centers. Since 80% of global electricity uses steam turbines, swapping in sCO2 generators without new facilities could rapidly scale capacity — and 33.5 million sq ft of US data centers built in 2025 alone generate waste heat sCO2 could recapture.