In a world where energy prices are skyrocketing, and energy shortage and rationing are the order of the day, people are turning to solar panel systems to generate electricity.
So what are the different types of solar tracking systems, and how do they work? There are two main solar tracking system types: single-axis and dual-axis solar tracking systems. Single-axis solar trackers track the sun from east to west; they rotate on a single point and move either in unison, by panel row, or by section. On the other hand, dual-axis trackers rotate on the X and Y axes which helps the panels track the sun directly.
However, to optimize solar panels’ efficiency, they should be installed facing the right direction. Better yet, did you know that you can enhance the efficiency of your solar panels by installing solar tracking systems?
Solar tracking systems allow the solar panels to take advantage of the Sun from the moment the first light strikes the earth to the last.
And in this article, I will teach all you need to know about types of solar tracking systems and how they work. Without wasting any second, let’s bask in the sunlight.
If you are interested in exploring the difference between single-axis and dual-axis solar trackers, I wrote a whole article that I encourage you to read.
What Are Solar Trackers?
A solar tracker is a device fitted on solar panels that allows them to move with the Sun to absorb optimal sunlight and produce maximum energy. If you want to learn more about solar trackers, I have defined solar trackers in my previous articles, but let me simplify it here.
The Sun rises from the east and sets in the west, and if you have fixed solar panels, there will be times of the day when the panels are not optimal.
Most fixed solar panels are installed to face the Sun between midday and early evening when the sunlight is intense. But what about early morning and late in the evening? Most sunlight goes to waste!
And that is why solar tracking systems were designed. They rotate or turn your solar panels to face the Sun at optimal angles from sunrise to sunset.
You can call that improved efficiency, right? Although they are costly, there are some instances where they are ideal.
I hope I have made it clear. Watch the video below to explore how solar trackers work.
Types Of Solar Tracking Systems
You now know what solar tracking systems are and how they help improve your solar energy production.
So, let’s discuss the types. You can categorize solar tracker panels by the way they work or by the direction of their movement.
Don’t worry; we will discuss all of them.
Types Of Solar Tracking Panels By How They Work
Under this category, solar panel trackers are divided into manual, passive, and active solar trackers.
Let’s consider each type.
1- Manual Solar Tracking Systems
A manual solar tracker allows you to move or rotate your solar panels using morning, noon, and afternoon orientations.
You manually orient your panels to face the Sun when the Sun is overhead. You will do the same for the afternoon to increase their efficiency.
Manual solar tracking solar systems also have a mechanical implementation or settings you can change many times throughout the year.
Why? Because the Sun changes positions with the changing seasons.
Have you ever noticed that the position the Sun set two months ago is slightly different from where it sets now?
Check it out if you haven’t. So, a manual solar tracking system must have a setting that allows you to adjust the monthly panel orientation, considering the Sun’s changing positions during the year.
The manual solar tracking system is suitable for countries where labor cost is relatively lower. Otherwise, it will inflate your overall costs and make no sense.
2- Passive Solar Tracking Systems
Passive solar trackers use liquid Freon or another volatile and responsive liquid as a thermally active component. This low boiling point gas liquid is often stored in a bulb, and when heat from the Sun hits it, it condenses in certain areas, thus causing an imbalance. The imbalance tilts the panels to face the Sun at optimal angles.
However, passive solar tracker lacks precision orientation. Therefore, it is unsuitable for solar panel systems with concentrating photovoltaic collectors.
But if you plan to install normal PV panels, passive solar trackers will work well for you.
The liquid has viscous dampers that resist excessive motion caused by wind gusts.
Additionally, passive solar trackers have reflectors and shaders that help reflect morning sunlight. The morning sunlight will “wake up” the solar panels, tilting them towards the Sun.
This phase can take up to one hour, depending on the intensity of the sunlight. However, you can reduce this time by including self-releasing tiedown in the system.
What does a self-releasing tiedown do? It positions your passive solar panels slightly past the zenith in the evening to catch the early morning sun.
The only challenge is that passive solar tracking systems can be 25-30% costlier than stationary solar panel systems!
3- Active Solar Tracking Systems
Since passive solar tracking systems have a precision problem, the active solar system solves it. Active solar tracking systems use concentrating photovoltaic technologies that need high-precision solar tracking to enhance the systems’ energy conversion efficiency.
So, active solar tracking systems’ control algorithms manipulate and send signals to the actuators to achieve precise solar tracking. The algorithm sets the solar panels in the system a tenth of a degree tilt, thus concentrating sunlight on a small area with thermal receivers.
How does it work? Active solar tracking systems rely on outside sources of energy to function properly. You can use motors and other mechanical devices to provide the energy needed to move the actuators.
And the PV system could also power the motors, which in turn power the system. So, the solar panels need outside power to rotate or move them in the Sun’s direction.
Furthermore, active solar tracking system algorithms ensure that the system consumes less energy and is protected against disturbances.
Active solar tracking systems can change the position of the solar panels to orient the system perpendicular to solar rays. This will increase the amount of energy the system generates.
The system achieves better power production because of its components, including:
- Sun position sensors.
- Transmission mechanical subsystems.
- Solar position algorithms.
- Electric motors.
- Control units.
- Limit switches.
However, you should remember that an active solar tracking system can move the panels in one direction (single-axis trackers) or two directions (dual-axis trackers). We will discuss these trackers in the next segment.
That takes us to the second way of categorizing solar trackers… direction.
Types Of Solar Trackers By Mode Of Motion
We can categorize solar tracking systems by how the panels move as they follow the Sun. Let’s dive into it.
1- Single-Axis Solar Tracking Systems
Single-axis trackers have their PV surfaces tilted at an ideal angle to help them absorb maximum sunlight. The system rotates the solar panels around one axis.
The tracker helps the panels to move with the Sun from east to west and change their angle depending on the Sun’s position.
A single-axis tracking the sun is sufficient and offers a lower-cost solution to your energy needs. They are better than fixed solar panels, producing 25-35% more energy (Source: sciencedirect.com)
Types Of Single-Axis Solar Panels:
Single-axis solar panel trackers are also categorized into different types. Wouldn’t it be nice if you knew them?
- Horizontal single-axis tracker (HSAT): It rotates east to west on a fixed axis parallel to the ground. It is one of the PV applications’ cheapest active tracker configurations since it needs less construction material.
- Horizontal tilted single-axis solar tracker (HTSAT): It resembles HSAT but has a certain tilt. You need a concrete foundation to build, which adds to its cost.
- Vertical single-axis solar tracker (VSAT): This tracker is installed in an east/west or north/south orientation following an up-down movement of the Sun. You will likely see them in mountainous regions or extreme latitudes.
- Vertically tilted single-axis solar tracker (VTSAT): It operates like HSATs except it has a vertical tilt instead of a horizontal one. It also produces more energy than its horizontal counterparts.
This brings us to…
2- Dual-Axis Solar Tracking Systems
Unlike single-axis tracking systems that only move on one axis and one direction, dual-axis solar trackers can rotate the panels from north to south and east to west.
Since the Sun’s azimuth and altitude angles change regularly, dual-axis tracking device track the Sun wherever it moves, thus collecting more solar energy than fixed panels or single-axis trackers.
A two-axe tracker generally has two free degrees of movement, allowing rotation around two axes (Source: sciencedirect.com)
Dual-axis solar trackers are divided into types: altitude-azimuth tracking and polar-axis tracking.
Let’s discuss them.
- Altitude-azimuth solar trackers: The Azimuth axis is perpendicular to the ground, while the altitude axis is perpendicular to the azimuth axis. This dual-axis solar tracker has a mirror or sunlight collector, and when it works, the collectors rotate to face the Sun, thus changing the azimuth angle.
- However, if the mirrors rotate around the altitude axis, they change the altitude angles. The collectors concentrate sunlight on thermal receivers, thus generating power.
- Polar-axis tracking: This tracking device has one axis of the concentrator or collector pointing to the north pole parallel to the earth’s rotation axis. In contrast, the other axis points perpendicularly to the polar axis.
- How does it work? The mirror rotates around the polar axis; however, its rotation speed is similar to the earth’s rotation angle but in the opposite direction.
Are Solar Trackers Worth It?
A solar tracker is generally not worth the investment for most homeowners. Investing in solar trackers to continuously adjust the orientation of your solar panels eventually is more money upfront and requires more energy. Nevertheless, solar trackers can be worth it, particularly for commercial builds.
What to read next:
- 7 Solar Panel Cleaning Equipment and How to Use Them!
- What Is The Average Electric Bill With Solar Panels?
- What is the Average Cost of Solar Panel Installation? (This much!)
- What Size of Solar Panel Do You Need to Charge a 100ah Battery? (This size!)
Solar tracking systems are exciting to learn but can also increase your solar energy production. Investing in a solar tracking system will increase your solar panel efficiency and reduce your electricity bill.
So, which type of solar tracking system do you want to install?