New solar panels deliver up to 690 W with 20 W more power from design changes

Chinese solar manufacturer Longi has introduced rooftop solar modules rated up to 690 W, using a conductive backsheet that replaces conventional soldered ribbons to boost output and reduce potential connection failures.

Unveiled at All Energy Australia 2026 in Melbourne on October 28–29, the Hi-MO X12 series targets residential, commercial and industrial rooftops.

The modules combine the company’s hybrid passivated back contact (HPBC) 2.0 cells with a redesigned electrical interconnection structure.

Longi said the design removes more than 15,000 potential solder-joint failure points per module. Australian pricing, initial shipment volumes and a commercial delivery schedule have not been disclosed.

Metal foil replaces soldered ribbons

The new architecture embeds conductive metal foil circuits within the module’s rear encapsulation structure. Solar cells connect directly to this conductive backsheet, replacing the conventional soldered ribbons used to link cells.

According to Longi, the design increases the current-carrying cross-sectional area by 85 percent, delivering an additional 6 W to 8 W compared with conventional interconnection designs.

The modules also incorporate what the manufacturer calls Full-Screen Technology. This combines shingled cell layouts with hidden busbars to reduce inactive areas and shading on the front of the module.

Longi attributes a further 8 W to 12 W gain to that arrangement, bringing the combined power increase to between 14 W and 20 W.

The company also claimed its ultra-thin stacking process reduces internal stress by 60 percent, while an integrated metal foil barrier cuts water vapor transmission by 90 percent.

Two formats for rooftop installations

The larger LR7-72WVD module, intended for commercial and industrial applications, offers power ratings from 660 W to 690 W. Longi reported a maximum module efficiency exceeding 25.54 percent.

The smaller LR7-54WVD series comes in four power classes between 495 W and 510 W. Its datasheet lists efficiencies ranging from 24.25 percent to 24.99 percent under standard test conditions.

This 108-cell, dual-glass module measures 1,800 mm by 1,134 mm by 30 mm and weighs 51.8 pounds (23.5 kg). It uses a black anodized aluminum frame, with 2.0 mm front glass and 1.6 mm rear glass.

The datasheet specified a temperature coefficient of -0.26 percent per degree Celsius, an operating range of -40°F to 185°F (-40°C to 85°C), and a maximum system voltage of 1,500 V.

Warranty covers 30 years of performance

The LR7-54WVD series carries a 25-year product warranty and a 30-year performance warranty.

Longi guaranteed no more than 1 percent degradation in the first year, followed by annual degradation of 0.35 percent. That corresponds to approximately 88.9 percent of the module’s initial power output after 30 years.

The datasheet lists front and rear static load ratings of 5,400 Pa and 2,400 Pa, respectively. It also specifies resistance to impacts from 25 mm hailstones traveling at 23 m/s.

IEC 61215 and IEC 61730 are listed among the applicable certification standards, alongside certification marks from TÜV Rheinland and TÜV SÜD.

At the Melbourne event, Longi also introduced its Hi-MO 9 Prime utility-scale module and displayed LongiBank 3.0 and OneMatrix energy storage solutions, together with its Longi Block modular photovoltaic system.

Source: https://interestingengineering.com/energy/longi-unveils-690-w-solar-modules