Ingenious DROMEC Winch System for Rotating Solar Fields

Floating Solar constructs rotating, floating solar fields as a sustainable solution for generating solar energy on water. These islands are the result of collaboration between various disciplines in the field of renewable energy. DROMEC Winches has made an ingenious contribution to this sustainable concept with a combined winch system.

Floating Solar designs the solar islands to withstand Dutch weather conditions. With maximum efficiency and minimal ecological impact, the system is truly unique. From the very beginning of the design phase, DROMEC Winches has been involved in the development of this concept. This close collaboration resulted in the realization of three solar islands at PWN’s water treatment facility in Andijk.

Control Software

What makes Floating Solar’s solar fields unique is the use of the winch system developed and controlled by DROMEC Winches. The Dutch company holds a patent on this system. With the help of Optimal Solar Tracking (OST), the solar islands achieve maximum output. The close collaboration between Floating Solar and DROMEC’s solar specialists ensured that all ingredients for optimization were present. The control software represents a unique solution in this sustainable development.

Ralph van Dijk, General Manager, states:
“This system is unique in the world on this scale. It is also a hallmark of Dutch innovation on water. The collaboration with DROMEC as both supplier and partner has been remarkable. Innovations like this demand the utmost from all parties, and it’s fantastic how we’ve complemented each other to achieve a successful project. With these sun-tracking Floating Solar islands, we need 25% fewer panels to achieve the same output.”

Electric Rotation

The electric winch system with its control unit is located onshore at PWN Andijk. A tensioned cable, with a pulling force of up to 3 tons, connects the winch to the islands. The solar panels are fixed at a specific angle on each island. Every solar island has its own winch combination with two cables running to the island. The winch combination maintains tension on both cables, pulling one in while releasing the other. The intelligent control system monitors how much cable is reeled in, based on the position of the sun relative to the island. This precise coordination allows the island to rotate continuously, minimizing shadows on the panels.

Geerart de Vree, engineer, explains:
“DROMEC Winches developed this control system, allowing us to position the islands very precisely. At night, the system rotates back so that it can catch the first rays of the sun the next day. The control system also calculates cable lengths so that the position and angle of the OST can be accurately determined. From the start, DROMEC Winches has been involved in the calculation of the distance between the solar panels and the angle at which they are positioned. Especially in winter, when the sun is low, it’s important that the panels still generate enough energy. We refer to this as shadow-avoiding pulling. On an annual basis, the island generates 2000 MWh, equivalent to powering approximately 650 households.”

Island Position

The position of the solar islands is monitored from the initial setup to ensure the starting point aligns with the sun’s position. Using the unique winch system, the islands can be remotely tracked. The island can always be rotated to a safe position for maintenance or when extreme weather conditions are forecasted, a practice known as Weather Risk Management. With this project, DROMEC contributes to a sustainable and energy-efficient future!