Elastic-Flexible PV Mounting Structure

Egret Solar recently signed a contract with a French solar company of the elastic pv mounting structure, or say flexible pv mounting structures.We have professional technical team of research and development of elastic pv mounting structure. We have projects within China these years. Now it is the first time Egret export elastic pv mounting systems overseas.

Since 2021, flexible/elastic mounting supports have gradually appeared in the bidding and procurement of the owners. Many EPC enterprises such as Datang, China power construction, Guodian Nanzi and state power investment have successively invited bids for about 1GW elastic supports. In last year's Huaneng 550MW photovoltaic EPC bidding, the lowest total package price since 2021 was almost quoted. According to an insider, one of the reasons is that flexible supports are used in a certain bid section. On complex terrain power stations, the construction cost of flexible supports is far lower than that of conventional supports.

In fact, the flexible support is not a new technology. It has been applied in previous pioneer projects. With the development of technologies and the development of photovoltaic projects in recent years, the flexible support has begun to play its unique economic and technological advantages in terms of cost and environmental adaptability, and has gradually been sought after by the owners. At the sixth new energy power station design, engineering and equipment selection seminar hosted by photovoltaic companies in October 2021, Gu Huamin, chairman of Xihe Power Co., Ltd., and he Chuntao, special expert of Ludian Guohua (Shandong) Electromechanical Equipment Co., Ltd., shared relevant information on flexible supports. This article is arranged according to the content of the speech, for the reference of readers only.

Due to its unique structure, the flexible support has a wide range of application scenarios, such as sewage treatment plants, agricultural light complementation, fishery light complementation, mountain photovoltaic, and parking lot photovoltaic.

In terms of structure, the flexible support can be generally divided into single-layer suspension cable system, prestressed double-layer cable system (load-bearing Cable + stabilizing cable), prestressed cable network, hybrid system, beam string (beam, truss) + cable arch, chord dome, lateral stiffening + and other structures. The structure type of long-span prestressed suspension cable flexible support includes load-bearing, component cable, cable truss strut, pile column, side anchor system, steel beam, cable truss strut and other key parts.

"The component cable is the inclination angle of two components forming a component, which can be adjusted between 10 degrees and 20 degrees. There is no sag and no azimuth angle of the component, and it can be arranged completely due to the south. It is a concept of through cable; the bearing cable under the component bears most of the force and wind load of the upper arch, and the three cables form a double-layer cable structure; and then a three-dimensional cable network structure is formed through the bracing rods between the cable trusses", Gu Huamin believes that this structure is not the most complicated or the most dazzling, but I think it is the best way to combine cost and multiple application scenarios. The single-layer cable structure that is cheaper than it is difficult to achieve a large span. The structure with long suspension beam can achieve a larger collapse distance, but the cost is high. In general, this structure is the most suitable for promotion. "

In fact, the flexible stent has been iterating in technology and structure in recent years. He Chuntao said: "The first generation of flexible supports solved the problem of large span and high headroom. However, due to the use of steel wire rope as the component support, the components were twisted under the action of strong wind, and the collision caused the photovoltaic modules to crack. Through improvement, the double-layer prestressed cable structure was adopted to support the photovoltaic modules and the inter row connecting rods were added, which solved the problem of the first generation of flexible supports that were prone to crack. In the second iteration, the high-strength and low relaxation prestressed galvanized steel strands were used as As the support of photovoltaic modules, it not only solves the problem of easy cracking, but also further simplifies the support structure and reduces the cost. "

This suspension cable requires very high piling requirements, so the error requirements are not If it is more than two centimeters, it should be handled in time. It needs to be emphasized that the commonly used PHC pipe pile is laminated, and it is not compressive. PHA pile should be used for compression. However, there is no national standard, only industrial standard. Therefore, there should be a large margin in the design. According to the geological conditions, the front and rear rows of piles are used, and the depth of driving is about 8 meters. "

In terms of standards, Egret flexible supports have applied to the photovoltaic industry association to prepare the general guidelines for the setting of photovoltaic flexible supports.

There is no doubt that the flexible support is becoming the focus of research and adoption by the owners of power stations. Especially with the reduction of land resources suitable for ordinary photovoltaic projects in China, the high land cost makes the owners of power stations begin to overcome the mountain photovoltaic with complex land environment, which also brings the spring of flexible support.