technical review

smart solar tracker

Smart Solar Tracker is designed to maintain angle in a horizontal and vertical position of mounted on it device/collector. In our case the Smart Tracker was used for appropriate alignment of tilt, pan, roll angles of photovoltaic panels corresponding to geographical location in relation to the changing position of the sun, in a way, so that sun rays fall on modules fixed on the panel, at an optimal angle to reach the possibly longest time period of maximal power production over every day in the year.

This solution greatly improves efficiency of photovoltaic modules. Measurements taken at an altitude of 51 °N, indicate that energetic efficiency of photovoltaic panels fixed on our rack, over the whole year, increased by 40% in comparison to modules with the same power, fixed on a roof surface in a standard way with direction of 0 °S and tilted at a 35° angle.

Such increment of efficiency allows to greatly limit cost of investments and save space that is necessary to achieve assumed efficiency of the whole installation. Introducing an inexpensive and easy in maintenance and repair design is a condition to achieve this goal.

Well known solutions

In the current market there are solutions which allow to modify the position of photovoltaic panels in one or two planes. However, available constructions are designed to handle too small number of panels on a single rack, to make the purchase of such system to be economically reasonable. The reason of limiting the size of the panel surface is inability to expose as-is design to unfavorable atmospheric conditions, e.g. wind force. Suggested rack designs, e.g. of a column type, absorb essential amount of produced energy to position the panels, especially when we deal with the influence of air masses.

So far, producers use centrally positioned column, in order to apply central mounting of a bearing what results in a lack of possibility to use a drive mechanism other than the one based on a toothed rim. Column based solutions cause an increase of rack production and raise the cost of the whole system.

technical disadvantages

Some devices that may be found in the market, allow for installation of the larger number of modules, however, they are costly in production because of an expensive method of bearing mounting and an expensive drive for the column structure. Large non-modular elements, force the need for special type of transport and specialised tools and competences for installation. That results in inadequate design-related costs. Such approach of create an extensive farms which have relatively poor return rate of the investment.

Central column alternative

After the analysis of market possibilities we decided
to design from scratch two kinds of solutions, whit most important features:

  • Modular installation system, that allows to use decentralized process of production - also in facilities with a low availability of technology. Further enables to maintain an optimal business model and supply chain.
  • Inexpensive, dedicated drive system of a high precision. Regardless of the type of used motors (step motors, BDC, DC), it is able to provide continuous tracking of the sun using the same electronics.
  • The solution that provides as well wide scope of adaptation as low susceptibility to interference. Flexibility in anchoring the structure to the ground. Possibility to install the device on poles driven into the ground.
  • Possibility to install the system on top of the flat roofing or gable roofing

Smart Tracker approach

Because economically optimal diameter of the system should be equal to a minimum of 1.5m in radius, the Smart Tracker guide has to have a modular structure, which allows to achieve this assumption without logistic constraints which appear in solid elements. Relatively large diameter of the guide in relation to the height of the rack allowed to acquire three very important and unavailable for other designs, features:

  • Low energetic requirements of the electric motor designed for the drive system responsible for positioning the set in the directions: east – west. It was also possible to apply a small stepper motors in order to increase the precision of rotary movement - The motion of the set which follows the sun position, means a turn of about 0.25 degree per one minute in dependence on a time of the day and year.
  • Simplified structure of mechanical gears, translates into lower energetic losses of the drive. With so large diameter of the set, the system is able to obtain much larger torques, what further enables the usage of a smaller and less expensive worm drive, whit self-braking stability to provide the rack positioning, even when the power supply of the motor is set off.
  • Increased stiffness of the system, based on features of the frame construction and obtaining larger spaces between support points of the main frame, therefore also the upper frame. It minimizes the risk caused by gusty winds which accompany increasingly intensified climatic anomalies.
  • Option to install the rack on a gable and flat roofing structures. The construction itself is balanced enough so that anchoring is treated as a security element and not required.
  • Opportunity to eliminate expensive foundations, requiring documentations and also official construction notification in favor of the ballast or screw-in ground anchors. The process significantly decreases the cost of large installations, it is possible to be done with usage of automated equipment. Insignificant environment influence – the anchors may be dismounted with usage of the same machine. In case of small installations the ballasts enable to make the construction mobile. - to use it as power source in places without a power form grid.

Increased stiffness of the design and frame based structure also enabled to eliminate a weak point of the construction which resulted from imperfections of market available drives designed to tilt the working plane. Engineers commonly use linear motors based on a trapezoidal screw. With mounting as shown on the exemplary figure;

wind load graph

Because the mounting of the linear actuator on a pole structure has to be done in a way that enables the movement of the mounting together with the upper frame, the size of the actuator and its parameters must be significantly limited. The weakness of this solution manifests with a low resistance to a jerk of waving plane working on the wind. The wavy motions are a result of combination of dynamic force of the wind and gravity. The size of the working plane increases the torque that is transferred by the constructions to the linear actuator.

deformations on working plane one and two-column stand exposed to the wind

Usage of the dedicated slide drive enables to acquire a beneficial stiffness of the structure, and in addition, in the moment of adjusting working plane to the horizontal secure position (similar to the parallel position towards the earth), it greatly increases the resistance of the system on influence of strong and gusty winds. Most of the controllers available in the market, after connecting a wind gauge, enable to set the rack in a default and safe position in case of detection of threshold speed of the wind. Default position in actual working conditions is not always optimal because of the terrain shape.

the default safe position of the working plane in real field conditions

Our dedicated slide drive also plays a reinforcing role for the main frame, because its guide is integrated with the elements of the whole framing by skeletal structure.

reliable dedicated slide system


with the Smart Solar Driver philosophy.


a significant progress in the development of renewable energy sources is now possible.

Previous philosophy

Breaking the stereotypes

Time to disrupt the artificial division of drivers for those operating in closed and open systems. This division results from assigning certain precursors of particular solutions to the technology, what further causes stagnation in driver development. In the current market there are only a few of products which bring satisfactory results in tests. All of the remaining solutions focus mainly on theoretical issues and not on constructive aspect for the market needs.

By using developed nomenclature, closed systems will work fine in tropical regions with insignificant occurrence of cloudiness – only in places where rainy seasons or any other climatic changes in the environment between seasons are minimal. Open loop systems, in the form of pure algorithm, will be able to solve problems of unstable irradiation, however, their usefulness is rather laboratorial.

The REI vision assumes a conception of a driver which exceeds the current level of technology, a driver which successfully realizes a concept of hybrid system and at the same time is fully configurable and manageable. A driver which leaves the choice for a user. We abolish restrictions produced by a conventional division resulting from inflexibly coded operational logic.

REI Driver opens unlimited possibilities, thanks to the usage of efficient IoT platforms, which allow to relatively easily, change implementation of primary and secondary algorithms, therefore to control the behavior of the whole system.

By supplementing algorithm calculations with transformations of data ongoing from sensors and unlimited number of peripherals, it is possible to run auto-calibration of the system even in the most harsh field conditions.

We open the way to facilitate collection of data for further research. We enable a mutual correction of operation of cooperating racks in a master-slave configuration. Therefore, we create an opportunity to use machine learning or artificial intelligence for more sophisticated applications

Continues improvements in

Smart solar driver

  • Ability to operate in a mode of continuous adjustment of motors to changing angular velocity of the earth or to operate in the system of interval start-ups.
  • Possibility to follow the sun which is partially covered by clouds, preserving the highest precision.
  • Non-susceptibility to short-lasting and frequent, small cloud covers, providing a minimal extent of motor operation required in tracking process.
  • Flexibility in configuration of motor types, a user may choose among: step motors (controlled directly or with dedicated controller), BLDC motors or DC motors (with single or two-phase encoder or without it).
  • Configurable control platform for gears, providing possibility to use a controller for any kind of a rack, regardless of its design and location.
  • Possibility to gather and analyze data in CSV file, xls/google sheets, database file or dedicated IoT platform.
  • Unlimited capabilities of fast development of software logic in order to adjust to specific location needs.
  • A modern WWW interface, with a package of tips displayed in the process of configuration of base parameters of the device.