China Sets 23.2% Minimum Solar Efficiency to Curb Oversupply, Effective January 2027

China's National Administration of Standardization published, on June 27, 2026, three mandatory national standards setting a minimum efficiency of 23.2% for TOPCon and heterojunction (HJT) solar modules, effective January 1, 2027, as reported by pv magazine. The move aims to contain nearly two years of severe oversupply that has driven global panel prices sharply lower.

The new standards (GB 29447-2026, GB 47835-2026, and GB 47834-2026) cover the full production chain: polysilicon, monocrystalline silicon wafers, crystalline silicon modules, and grid-connected inverters. For Mexico, which imports more than 90% of its photovoltaic modules from China, the standards redefine the equipment pool available for the 22 GW of solar capacity outlined in the Ministry of Energy's (SENER) 2030 plan. The rules establish three efficiency grades, with Grade 3 as the minimum required for access to the Chinese market.

Grade 3 thresholds are 23.2% for TOPCon and HJT modules, and 23.5% for back-contact (BC) modules. On bifaciality, the floors are 75% for TOPCon, 85% for HJT, and 70% for BC. According to Caixin Global, centralized TOPCon modules were priced this week at 0.7 yuan per watt (W), with transactions ranging from 0.65 to 0.80 yuan/W, levels near the cost of production, according to InfoLink data. SMM analyst Zheng Tianhong noted that leading manufacturers alone can cover current demand, limiting any near-term improvement in the supply-demand balance. The heaviest impact will fall on legacy PERC (passivated emitter and rear contact) lines and energy-intensive polysilicon plants.

State-owned enterprises and Chinese government-backed projects are expected to adopt the new thresholds as a procurement requirement in their tenders, shrinking the market space for low-efficiency supply. For developers in Mexico and Latin America, the low-price acquisition window remains open through 2026, but the available module mix will shift toward higher-efficiency products from 2027 onward.

This article was drafted with the assistance of artificial intelligence from verified sources and reviewed by a human editor before publication.