China’s Solar Industry Is Crushing It On Solar Conversion Efficiency

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Last Updated on: 14th April 2025, 11:35 am

Intentionally or not, the malevolently incompetent Commander-in-Chief who occupies the White House has all but guaranteed that China will continue to dominate the global solar industry, leaving the US behind in the dustbin of history. Exhibit A is the Chinese solar manufacturer LONGi Green Energy Technology, which has just unveiled a new 670-watt module with a conversion efficiency of 24.8% at a showcase in Anhui, China.

24.8% Conversion Efficiency For A TOPCon Solar Cell

LONGi emerged as an early leader in the global solar industry. In 2020 the startup became the first manufacturer to ship more than 20 gigawatts’ worth of solar modules, a feat that demonstrates how far, and how fast, the industry has grown. Just 10 years earlier, the total number of solar modules deployed by all manufacturers together barely topped 17 gigawatts.

The company has been very busy since 2020. Last week LONGi announced an upgrade to its flagship Hi-MO 9 TOPCon solar module, which is a BC (back contact) module designed with the electrical connections on the rear of the cell to keep the sun-facing surface free of interruption.

As described by LONGi, the upgraded Hi-Mo 9 achieves an industry-leading solar conversion efficiency of 24.8%. That represents a power improvement of 10 watts and a peak of 670 watts over the previous Hi-MO 9 module.

LONGi also claims that the new module is 1.5% more efficient than other TOPCon modules on the market, and it increases the installed capacity of a solar array by 6.4%, compared to other modules in the same amount of space.

What Is This TOPCon Of Which You Speak?

TOPCon is short for tunnel oxide passivated contacts, a relatively recent development in the solar industry aimed at improving solar conversion efficiency in silicon solar cells. In a review of the literature published last year in the journal Advanced Materials, a research team based in China reported that the International Technology Roadmap of Photovoltaics “forecasts TOPCon to become an important technology despite a few remaining challenges.”

The researchers also note that the global solar industry has yet to coalesce around a set of best practices for TOPCon manufacturing, but LONGi is not waiting around for that to happen.

The company has spent the past 12 months or so demonstrating the new Hi-MO 9 in the field. “In Hainan, China’s high-temperature, high-humidity environment, LONGi’s Hi-MO 9 module delivers a 1.89% per-watt energy yield advantage over conventional TOPCon modules,” the company states. The Hi-MO 9 also got a workout in Riyadh, Saudi Arabia, where LONGi cites a gain of 1.62%.

“Data from additional BC power plants further confirm the exceptional power generation capabilities of the HPBC 2.0-powered Hi-MO 9 module, underscoring its proven reliability across diverse global climates,” LONGi emphasizes, with HPBC referring to the company’s loss-reducing hybrid passivated back contact technology.

More Back Contact Solar Modules For The Global Solar Industry

To help nudge the developer side of the global solar industry into adopting its BC technology, last week LONGi also launched a competition called the “Global Optimal BC Solar Power Plant Design Challenge,” in partnership with the independent inspection services institution TÜV Rheinland.

TÜV Rheinland is tasked with evaluating the entries, taking into consideration innovation in design along with BC technology integration and other parameters.

“The competition, open to consultancies, EPC firms, and renewable energy investors worldwide, invites innovative designs for ground-mounted power plant projects exceeding 50MW across diverse application scenarios,” LONGi explains.

Hold on to your hats. LONGi also let word slip that its HIBC (Heterojunction Interdigitated Back Contact) silicon solar cells have just received a certification of 27.81% conversion from the Institute for Solar Energy Research Hamelin in Germany.

Here Comes The US Solar Industry

President Trump’s fossil-friendly energy policy aside, the US solar industry still has the potential to keep up its end of global production over the next 3.75 years until January 20, 2028, when Trump peacefully leaves office as stipulated in the US Constitution, and overseas investors are still eager to help.

Joint ventures with overseas firms to manufacture solar panels in the US have become a common feature of the domestic solar industry. That includes Longi, which partnered with the US firm Invenergy in a joint venture to establish a new factory in Pataskala, Ohio, under the name Illuminate USA. The facility began producing solar panels in February of 2024.

The 5-gigawatt, 1.1 million square foot facility hosts eight production lines capable of spitting out more than 9 million solar panels per year once revved up to full capacity. The 540-560 watt panels are marketed under the trade name “Illumina 5,” with a solar conversion efficiency of 21.7% (not to be confused with a hair product of the same name).

Illuminate USA announced its one-year milestone on February 6, noting that it reached the 2.5 gigawatt mark. “In just the first year of operation, the company achieved a major production milestone, manufacturing over 4.5 million solar panels, and growing to the largest producer in the United States,” the firm elaborated.

What About Those Tariffs?

Yes, what about them? Although Illuminate assembles its solar panels in the US, it depends on the global solar industry to supply components. As of February, though, Illuminate was not particularly worried about that. “Illuminate USA is well positioned to achieve its annual target of manufacturing over 9.2 million solar panels this year,” the company stated.

“The company is also focused on expanding its product offerings and investing in new technologies to maintain its leadership in the renewable energy sector,” they added.

In the meantime, solar power plant developers and investors are counting on an ample supply of solar panels to keep the US solar industry moving along. That includes a healthy assist from overseas investors. In recent weeks, for example, the US solar developer Sunraycer Renewables announced a $475 million financing deal with MUFG Bank, Ltd., Nomura Securities International, Inc. and Norddeutsche Landesbank Girzonentrale.

Another US solar developer, Silicon Ranch, recently received a boost of its own from the Netherlands firm AIP Management, to the tune of $500 million. “The solar developer has amassed a solar portfolio totaling 3.6 gigawatts, and is working towards a total of 10 gigawatts by 2030,” CleanTechnica noted.

Another renewable energy investment firm that came to play on a global level is Minnesota-based Excelsior Energy Capital, which closed its $1billion+ Excelsior Renewable Energy Investment Fund II on April 8. Fund II, which follows the previous $505  million Fund I round of 2021, is anchored by the Development Bank of Japan with an assist from limited partners in  Japan, Europe, Australia, and the Middle East as well as the US.

What was that about bringing back coal again?

Photo: The leading Chinese solar manufacturer LONGi aims to shake up the global solar industry with a new 24.8% efficiency rating for its Hi-MO 9 solar module (courtesy of Longi via PR Newswire).