Flexrow for solar trackers

In recent years, the use of solar trackers has increased significantly in several PV markets. This is especially the case with large panels in utilities. Using solar trackers, electricity production can increase by 30-40%. However, today’s actuators are a major cost driver in solar trackers and heliostats. An interesting and cost-effective alternative for large solar trackers and heliostats is a new hydraulic linear actuator technology, called Flexrow.

In short, the actuator is based on two connected short hydraulic cylinders, which are open at both ends, as if every other “climbs” on a fixed clamped piston rod by means of hydraulic clamping connections. In this way, the cylinder can travel along the rod, as two hands hauling in a rope with a load. It is based on well-known, robust and cost-effective standard components (COTS) for hydraulics. The patented technology, which is characterized by very slow movements, long strokes and high accuracy, represents a completely new actuator technology with new possibilities.

The actuator can withstand demanding desert and arctic environments. It can handle high forces and torques which may be generated on large solar panels and heliostats at high wind speeds. The characteristics of the actuator are its uniquely long strokes (up to 7-8 m), a compact construction and light weight. The actuator can be implemented in demanding environments, with respect to extreme temperatures, high or low humidity, dust, vibrations, shock loads, etc. In comparison with conventional hydraulic and electromechanical actuators, the technology can offer shorter, more compact and more easily placed actuator solutions with long strokes.

Furthermore, the technology does not have problems with backlash giving directional inaccuracies, which is common in heliostat applications in particular. The technology is based on well-known, robust and cost-effective standard components (COTS) and is light weight and material-efficient. Furthermore, it has high operational reliability.

A major cost driver in the design of large heliostats and solar panels with solar followers is the framework that can manage the loads the wind gives rise to. Wind gusts which create vibrations and material fatigue in the framework. These problems are common when operating with Azimuth elevation-based actuators with electro-mechanical drive.

One way to deal with these problems, that is to obtain a stable but still light weight, large framework, is to build solar tracker and heliostats on three legs with short pedestals using the new long-stroke actuator technology (a tripod). There are electro-mechanical actuators for linear movement, but these have a more limited stroke.

The expensive electro-mechanical actuators, so-called Azimuth Drive, have for a long time been one of the most important cost drivers for large solar trackers and heliostats. These drive systems also have problems with play, which in turn gives directional inaccuracies. With this new actuator technology, large solar panels and heliostats can be built more robust, cost-effectively and with lower weight. This technology can replace expensive azimuth drives. The new Flexrow technology for large solar trackers and heliostats provides an interesting cost-effective alternative for lower Levelized Cost of Electricity (LCOE).

Partners sought

With great experience in renewable energy and actuator technologies, but without the capacity to produce the technology themselves, the company is aiming to develop market leading actuators for dual solar tracker and heliostats technologies. Therefore, the company is now looking for a new cooperation with a manufacturing partner. The partner should preferably have developed and distributed commercial products in the past and have a sales department with international sales experience.