China’s first rooftop flexible-mount PV project goes online; a level‑13 sandstorm destroys 200MW of PV arrays in Kuqa

Against the backdrop of the deepening “dual carbon” strategy in 2022, the photovoltaic industry continued its rapid growth. As the “skeleton” of PV power plants, the mounting system segment faced a year interwoven with technological iteration and extreme tests. From the large‑scale application of flexible mounting systems in complex scenarios such as wastewater treatment plants, mountainous terrain, and fishery‑solar hybrid projects, to the destruction of over 200 MW of PV arrays caused by a rare sandstorm in Kuqa, Xinjiang – the tension between technological innovation and safety reliability became a focal point for the industry throughout the year.

Flexible Mounting Systems: A “Sharp Tool” for Efficient Land Use

For a long time, the PV industry has been constrained by land shortages. Against this backdrop, flexible PV mounting systems featuring “high clearance and large span” gradually became a new favourite in the PV market. A flexible mounting system is a large‑span structure that supports PV modules using pre‑stressed flexible cables fixed at both ends. The cable span is typically between 20 and 40 metres, and can reach up to 100 metres. Modules can be installed 2 to 30 metres above the ground, offering the advantages of high clearance under the modules and a reduced number of pile foundations. Compared with traditional fixed supports, flexible systems can significantly increase the module layout capacity, while using less steel, having a lower cost, and imposing smaller demands on site conditions – thus maximising land‑use efficiency.

In 2022, flexible mounting systems achieved breakthrough applications in several landmark projects in China. On 31 July, the 6 MW rooftop distributed PV project at Fengzhu Textile, invested in by Guoneng (Fujian Jinjiang) Thermal Power Co., Ltd., was successfully connected to the grid, becoming China’s first rooftop flexible‑mount PV project. The rooftop had many tall ventilation and lighting skylights, narrow spaces, and serious shading. After adopting a flexible mounting system, the number of PV modules increased by 7,359 within the same area, the installed capacity rose by about 4.3 MW, and annual power generation increased by 5.17 million kWh, achieving full layout under land‑constrained conditions.

Even more striking, in late November the Beihu Sewage Treatment Plant distributed PV power station project, independently developed and invested by China Energy Engineering Group Central Southern China Institute, achieved full‑capacity grid connection. This project set multiple national records: largest installed capacity for a sewage treatment plant, largest number of distributed large‑span flexible mounts, and largest single span of a flexible mount in China. Located inside the Beihu Sewage Treatment Plant in Qingshan District, Wuhan, the project has a total capacity of 23.7 MW. The modules above the secondary sedimentation tanks and biological tanks are supported by pre‑stressed flexible mounting systems, with an installed capacity of 23.1 MW, a steel column height of 8 metres, a maximum continuous span of 730 metres, and a maximum single span of 59.3 metres – currently the largest single span of any flexible mounting system in China. The entire project uses about 715 tonnes of steel and about 165 km of steel cables, significantly reducing the number of pile foundations and concrete usage, lowering costs, while the 8‑metre clearance ensures that the operation of both PV and water treatment facilities is unaffected.

In steep mountainous terrain, flexible mounting systems also demonstrated unique advantages. On 16 June, a 3 MW hydro‑solar complementary PV project in Wuzhou, Guangxi, entered its final stage. Located on irregular steep slopes with gradients of 35 to 45 degrees, where traditional mounting systems were difficult to install, the project team adopted a flexible cable‑suspended support solution, maximising the use of the idle hillside.

On 24 October, the Changjiang Institute of Survey, Planning, Design and Research publicly announced its independently developed flexible PV mounting technology. Recognising the shortcomings of existing solutions – such as susceptibility to wind‑induced vibration and micro‑cracking of modules – the R&D team innovatively proposed the concept of “rigid module purlin as a whole, flexible cable structure as support”, applying rigid purlins in a flexible mounting system to both protect the modules and increase the rigidity of the cable structure. The team has applied for more than 10 patents (three granted) related to this technology, and expected the application scale to exceed 100 MW that year. In addition, the team cooperated with Tongji University, Chongqing University and other institutions on wind tunnel tests to systematically evaluate the aeroelastic effect of the overall structure, and conducted 1:1 model tests in Wuxi to ensure safety and reliability.

On 8 December, at the 18th China Solar PV & Photovoltaic Generation Seminar (CSPV), a sub‑forum hosted by DAS Solar on “Large‑span Flexible Mounting Technology and Multi‑scene Applications” concluded successfully. Many experts stated that the large desert and Gobi base projects will be a very important new application scenario for Chinese PV in the next 5 to 10 years, and that flexible mounting systems can effectively address the problems of high land occupation and difficult multi‑purpose reuse associated with traditional supports, promoting the popularisation of integrated “PV+” models such as agro‑PV, forest‑PV, fishery‑PV, and pastoral‑PV.

Flexible but Not Strong Enough? Flexible Mounts Face a Test

However, the reliability of flexible mounting systems also faced a severe real‑world test in 2022. According to industry insiders, at a large fishery‑solar hybrid project in South China, some modules on flexible mounts were blown off during a wind that was no stronger than a level‑10 gale; the micro‑cracking condition of the remaining modules was unknown. Although the manufacturer’s technical data claimed the system could withstand typhoons of level‑13 or above, the actual performance fell short of the claims. Reports noted that more than 99% of new global PV capacity still uses traditional mounting systems, and flexible products remain at a small‑scale demonstration stage without extensive field validation. Particularly in typhoon‑prone regions, modules may twist and collide under strong winds, leading to micro‑cracking.

The Tragedy of Kuqa: Level‑13 Sandstorm Sounds a Safety Alarm

If the reliability debate over flexible mounts was only an internal industry discussion, then a severe sandstorm on 27 November in Kuqa, Xinjiang, sounded a loud alarm for the entire PV mounting industry.

On that day, Kuqa was hit by a level‑13 severe sandstorm. A large PV‑to‑hydrogen project under construction in Kuqa suffered widespread collapse, destroying more than 200 MW of PV arrays – a heavy loss. This project was the world’s largest PV‑to‑hydrogen project under construction at the time and China’s first 10,000‑ton‑scale PV‑to‑hydrogen demonstration project, with a total investment of nearly RMB 3 billion. The first phase included 300 MW of PV capacity, originally scheduled for completion and grid connection on 30 October.

Videos and photos from the site showed that a large number of PV mounting systems had collapsed, and most modules were damaged to varying degrees, some completely shattered. Employees from companies involved in the construction said the severe damage was caused by a combination of factors: on the one hand, extremely harsh weather – gusting to level‑13 or above and lasting nearly 12 hours; on the other hand, insufficient consideration of wind loads in the selection and design of modules and mounting systems, especially given that the project used very large‑format modules.

After the accident, some media analyses pointed out that the manually adjustable mounting system used for the PV arrays might have been a major cause of the heavy losses – such systems have a large wind‑resistant area, and when facing the wind, the back of the modules experiences a strong positive pressure, making structural failure more likely in strong winds. Zhang Haiping, chairman of Wuxi Haoyang New Energy Technology Co., Ltd., said in an interview that the manually adjustable support design used in the project was a simple imitation of his company’s patented technology, without mastering the design essence or having experience applying such supports in windy areas.

Insiders revealed that although the project adopted very large‑format modules, the overall cost was not significantly increased. “If you choose an aggressive solution, you must be able to bear the corresponding risks.” The laboratory environment for very large‑format modules is quite different from real outdoor conditions. “In areas like Kuqa, where sandstorms are frequent, the wind pressure on modules is highly uneven. What kind of tests are needed to match real outdoor conditions? There are no clear standards, either internationally or in China.”

Notably, other PV projects in the vicinity that were designed with different mounting systems remained stable during this extreme weather, with only a few scattered modules affected. This contrast highlighted the critical importance of proper mounting system selection and design quality.

Standards First: The PV Mounting Industry Enters an Era of Standardisation

Alongside rapid technological and market development, standardisation of PV mounting systems also made significant progress in 2022.

On 13 May, the National Energy Administration approved and released the industry standard “Photovoltaic power station tracking system and support manufacturing supervision guidelines” (NB/T 10931‑2022), which specifies technical requirements for the manufacturing supervision of tracking systems and supports for PV power stations, covering raw materials and components, parts processing, finished product assembly, and testing. The implementation date was 13 November 2022. The standard was drafted by China Datang Group New Energy Science and Technology Research Institute Co., Ltd., Arctech Solar, and Fujian Antai New Energy Technology Co., Ltd., marking the beginning of a regulated phase for manufacturing supervision of PV mounts.

In September, the group standard “Technical guidelines for design and installation of flexible photovoltaic support structures” of the China Photovoltaic Industry Association (CPIA) successfully passed technical pre‑review. The standard was led by Tongwei New Energy Engineering Design Chengdu Co., Ltd., covering design provisions, load and load combinations, structural systems, component design, connections and joints, foundation design, anti‑corrosion, and installation. The expert group unanimously agreed that the standard, taking into account the characteristics of the existing flexible support industry and local conditions, is well‑compiled, demonstrates guidance and innovation, and will be instructive for the design and installation of flexible supports. As the first industry guideline for flexible supports, the standard will lay a foundation for the implementation and scaling of the technology.

On 4 August, the CPIA held an online seminar on the development status and application prospects of PV mounting and tracking systems, inviting industry experts to analyse in depth topics such as application scenarios, operation modes, cost‑effectiveness, and the development status of intelligent tracking systems. More than a thousand industry professionals watched the live broadcast.

Tracking Systems: Steady Increase in Penetration Rate

In 2022, the application of tracking systems in the domestic market also made significant progress. According to CPIA statistics, driven by the substantial increase in ground‑mounted PV capacity, the market share of tracking systems in China reached a relatively high level of 12% in 2022. The annual report of Arctech Solar showed that its tracking system shipments in 2022 increased by 43% compared with 2021, a substantial growth in shipment scale.

Tracking systems can actively adjust module orientation to track the sun’s position, maximising solar irradiance and achieving about 30% more power generation compared with fixed supports. As large desert and Gobi base projects accelerate, the penetration rate of tracking systems is expected to rise further. Institutions estimate that by 2025, the total mounting system market will reach RMB 117.7 billion, of which the tracking system market could reach RMB 65.1 billion, with a compound annual growth rate of 20.0%. Over the next five years, the growth rate of tracking systems is expected to outpace that of fixed supports.

In overseas markets, on 9 November, US‑based GameChange Solar launched a new fixed‑tilt mounting system for ground‑mounted power plants, the MaxDensity. Using an east‑west horizontal layout, it achieves up to 98% ground coverage ratio and can withstand wind loads of up to 120 mph and heavy snow loads. The company claims a global cost as low as USD 0.029 per watt.

In December, Arizona‑based solar technology company Erthos signed an agreement with Texas‑based developer Industrial Sun to build a more than 100 MWDC ground‑mounted PV power plant in Texas. Unlike traditional mounting systems that require 5 to 6 acres per MW, Erthos’s “ground‑mounted” solution requires less than 2.5 acres per MW, more than doubling energy density compared to conventional systems, while reducing the levelised cost of solar electricity. This project became the largest contract Erthos had received to date.

In Canada, engineering‑procurement‑construction company Dependable Group of Companies installed a 48 MW solar project portfolio in Alberta, using Solar FlexRack fixed‑tilt mounting systems. The project is expected to provide clean power to more than 22,000 homes.

Cost Reduction Must Not Come at the Expense of Power Plant Safety

Looking back at 2022, the PV mounting industry made substantial progress in technological innovation, scenario expansion, and large‑scale application. However, the painful lesson from the Kuqa project reminds the industry: cost‑reduction demands must not come at the expense of power plant safety. As China Energy News stated in its report: “Innovation is the driving force for industry development, but rigour is the basic requirement for sustainable industry development.”

In areas prone to severe weather, the application of very large‑format modules and new mounting system solutions requires greater caution. PV power plants, as infrastructure intended to operate for 25 years, depend on the design, selection, and construction quality of their mounting systems for their entire life‑cycle safety, reliability, and return on investment. With the implementation of relevant standards and the accumulation of industry experience, PV mounting systems are expected to find a better balance between technological innovation and safety reliability, providing even more solid support for China’s “dual carbon” goals.