Longi unveils anti-dust back contact solar module with 24.8% efficiency

Longi has launched its Hi-MO X10 anti-dust solar panel at the China (Jinan) International Solar Energy Utilization Conference.

The new module series uses Longi’s second-generation hybrid passivated back contact (HPBC 2.0) cell technology. It includes seven models, all with a uniform half-cell (6×24) design and dimensions of 2,382 mm × 1,134 mm × 30 mm. Power output ranges from 640 W to 670 W, with efficiency between 23.7% and 24.8%.

Under standard test conditions (STC), open-circuit voltage (Voc) is 53.70 V to 54.30 V, while under nominal operating cell temperature (NOCT) conditions, it ranges from 51.04 V to 51.61 V. Short-circuit current (Isc) varies between 15.13 A and 15.60 A. The temperature coefficient is -0.26% per degree Celsius. Longi said the module’s initial-year degradation rate is 1%, with annual degradation capped at 0.35% over 30 years.

The company integrated an anti-dust technology into the Hi-MO X10 series, which it claims increases theoretical energy generation per unit area by more than 10% compared to tunnel oxide passivated contact (TOPCon) panels.

First introduced in October 2023 with Longi’s first-generation BC products, the anti-dust technology has undergone more than two years of testing. Longi said the feature improves per-watt energy output by 2%. Combined with HPBC 2.0, the Hi-MO X10 series reportedly delivers up to 10% higher energy yield than competing TOPCon modules.

Longi’s internal calculations estimate that installing Hi-MO X10 (660 W) panels on a 10,000-square-meter rooftop would generate 189,000 kWh more per year than a 630 W TOPCon module setup, translating to an annual revenue gain of CNY 113,000 ($15,700). Over a 30-year lifecycle, this could amount to approximately CNY 2.67 million in additional earnings.

Longi outlined three key advantages of the Hi-MO X10 over conventional TOPCon panels:

• Anti-Dust Design: A redesigned frame allows rainwater to remove accumulated dust, reducing maintenance costs and preventing hot spots. Field data shows the feature provides an average energy gain of 2.04%, with peak gains reaching 6%.
• Shade-Tolerant Performance: The panel’s design redirects current flow around shaded areas, minimizing power loss. Longi claims this reduces shading-related losses by 70% compared to standard TOPCon modules.
• Fire Prevention Mechanism: The module lowers the risk of thermal hotspots from shading caused by bird droppings or leaves. Lab and field tests show that under identical shading conditions, the Hi-MO X10’s local temperature remains around 80°C, while conventional TOPCon panels can exceed 130 C, reducing fire risks.