As global photovoltaic installed capacity continues to climb, improving the power generation efficiency of existing power stations has become a key industry focus. In 2023, a seemingly insignificant accessory—the solar panel drainage clip—experienced explosive growth worldwide. Throughout the year, from Europe to Asia, numerous companies launched innovative products, and even industry giants filed related patents. Their goal was to tackle the persistent issue of dirt and water accumulation at the bottom of modules, achieving a 2% to 12% increase in power generation at a very low cost.

The Challenge of Soiling: A Neglected Efficiency Killer

For a long time, because the module frame is higher than the glass surface, after rain or cleaning, water droplets gather at the bottom edge of the module due to surface tension. This not only leads to the accumulation of dust and mud, forming a “mud belt,” but over time it can cause hotspots, shading, and even module corrosion, seriously affecting power generation efficiency and module lifespan.

To solve this problem, in 2023, several specialized companies and startups introduced their own solutions. The principle is the same: using a physical structure to break the surface tension of water and guide the accumulated water away.

International Developments: European, American, and Asian Manufacturers Show Their Strengths

Solarud (Portugal): Pioneer of the Smart Clip

As early as March 2023, Portuguese startup Solarud launched its “smart drainage clip.” Founded in 2022 by three engineers, the company focuses on improving PV system efficiency through simple and reliable solutions. Its Solarud Nextgen clip fits frames 28 mm to 40 mm thick and is claimed to increase power generation by an average of 3.5% over 25 weeks. The product line also includes a “Nano” version suitable for modules with low tilt angles (less than 15 degrees). In its 2023 blog posts, the Solarud team also emphasized that thoroughly cleaning the modules before installing the drainage clips is crucial, and they recommend installing at least two clips per module to cover water accumulation at the bottom corners.

Prasham Greens (India): Aiming for a 10% Power Boost

In July 2023, Gujarat-based Prasham Greens designed and launched drainage clips suitable for 35 mm and 40 mm frames. Company CEO Jainam Shah told PV Magazine that to address the tendency of ABS material to become brittle under sunlight, they specifically added four chemical additives to extend the product’s life to 10–12 years. The company claims its drainage clips can increase power generation by 2% to 10%.

Van der Valk Solar Systems (Netherlands): New Plant and Product Iteration

In September 2023, Dutch company Van der Valk Solar Systems, while celebrating its 60th anniversary and the inauguration of a new factory, announced that its product line now includes “drainage clips.” The company noted that precipitation can cause water stains and dirt to accumulate at the bottom edges and corners of modules, affecting efficiency. Its drainage clips work on the principle of a liquid-level equalizer, are made of UV-resistant plastic, and are recommended to be installed in pairs at one‑third and two‑thirds of the module length.

Innovation from the Open‑Source Community

In addition to commercial products, in April 2023, the open-source 3D model platform Printables featured a solar drainage clip design based on capillary action. The design allows users to print the clip themselves according to their module’s frame dimensions (e.g., 30 mm height, 11 mm thickness), sparking enthusiastic discussions and modifications among DIY enthusiasts worldwide. This phenomenon also reflects the high market interest in such products.

Chinese Momentum: Patent Filings and Industry Leader Entry

In 2023, Chinese companies in the photovoltaic supply chain also made frequent moves in the drainage clip sector, demonstrating strong manufacturing and innovation capabilities—from utility model patents to scaled production.

Jiangsu Shengyuan: Quantified Power Gains

In April 2023, Jiangsu Shengyuan Energy Technology Co., Ltd. introduced its self-developed “plastic PV module drainage and mud removal clip.” Based on field test data, the company pointed out that after installing the drainage clips, dirt accumulation at the bottom edge of the modules became nearly invisible, and the power generation gain ranged from 2% to 12%, with an average increase of nearly 4%. The product supports various frame thicknesses from 25 mm to 45 mm and has an expected service life of more than eight years.

LONGi Green Energy: Drainage Device Patent Application

At the end of December 2023, LONGi Green Energy, a global PV leader, was granted a new utility model patent titled “Drainage device and photovoltaic system.” The patent describes a split-type drainage device that connects to the module frame via a fixing part, designed to drain away water accumulating on the light-receiving surface. This move marked the entry of a top-tier industry player into this niche area from a systematic perspective.

Zhuhai Shangfang: Patent Grant and Pledge

Around the same time at the end of 2023, Zhuhai Shangfang Clean Energy Technology Co., Ltd. was granted a patent for its “drainage clip and photovoltaic panel” (CN220234590U). The patent features a design with first and second drainage holes to improve water flow and drainage effectiveness. The patent was also pledged for financing rights at the end of 2024, indicating its technological value has gained recognition at the capital level.

Summary of Key 2023 Developments in PV Drainage Clips