Offshore empirical project finds 2.43% higher cumulative energy yield for LONGi modules compared to TOPCon

At the Yantai offshore photovoltaic test base inChina's Shandong Province, LONGi's HPBC 2.0 modules recorded 2.43% higher cumulativeenergy yield per installed kilowatt than theTOPCon comparisonmodules between4January and 30 March 2025.The highest single-day advantage reached 6.77% on 29 January. Operated by China's National Photovoltaic Product Quality Inspection Centre (CPVT), the facility is described as China's first deep-sea floating PV empirical projectand provides an outdoor testing environment for evaluating photovoltaicperformance under coastal conditions.

Yantai’s coastal climate provides varied conditions for photovoltaicfield testing

Located in Yantai, Shandong Province, the testsite experiences a monsoon-influenced coastal climate with hot, rainy summersand cold, relatively dry winters. Seasonal variations in temperature, irradiance and cloud coverprovide different conditions for evaluating photovoltaic performance. The observation period from January to March 2025 covered winter and early spring,allowing the two module technologies to be compared under the conditions experienced during those months.

LONG’s back contact technology HPBC 2.0 achieves 2.43% higher specific energy yield in the Yantai comparison

Under these seasonal conditions, two 18-module arrays were installed for comparison. To keep the comparison controlled, both arrays were configured with the same total module area of 18 × 2.701 m². The BC array uses LONGi HPBC 2.0 modules rated at 635 W, while the comparison array uses TOPCon modules rated at 615 W. Daily power generation data were collected to calculate cumulative yield per watt and the BC gain, covering 4 January to 30 March 2025 for cumulative comparison and 4 to 30 January 2025 for single-day analysis.  Over the full period, backcontact modules delivered a 2.43% higher cumulative yield than TOPCon, achieving 40.74 kWh/kWp compared with 39.78 kWh/kWp, with a peak single-day gain of 6.77% on 29 January 2025.

CPVT provides independent testing under offshore conditions

China’s first deep-seafloating PV empirical project is operated by CPVT, the National Photovoltaic Product Quality Inspection Centre and an IECEE-recognised CB laboratory. The Yantai facility provides long-termmonitoring of PV modules, inverters, mounting structures and related materials under offshore conditions, including highsalinity, strong winds, wave loads and high humidity.