What do solar trackers do? What are their limitations and ultimately are they worth the investment in the UK?

In this guide we will cover the various pros and cons of solar trackers, their limitations and costs, so that you can make an informed decision whether or not to include them in your solar array installation.

Let’s start…

Please note: solar trackers are typically not used for domestic roof installs, they are too heavy and costly and so are mostly used in the context of commercial solar installs.

What are Solar Trackers?

As their name implies, solar trackers help your solar panels track the movements of the sun during the day, helping to maximise the amount of sun that hits them and therefore maximise the power generation.

A solar tracker is able to tilt and change the angle of the solar panels for ground mounted solar arrays.

Typically, solar trackers are not used for residential ground-mounted installs.

This is largely due to the costs involved, as well as the added maintenance they require, making them more suitable and common in commercial solar setups.

How do solar trackers work?

As discussed, a solar tracker tracks the movement of the sun and adjusts the solar panels, so that the sunlight rays maintain a perpendicular angle to maximise energy production.

This is in contrast to regular solar array installs that do not move, in which case the sunlight hits the panels at varying angles throughout the day.

The angle at which the sunlight hits the panels is referred to as the angle of incidence.

Essentially, the narrower the angle of incidence, the more power is generated.

Therefore by keeping the solar panels tracking the sun, they are perpendicular to it and so are able to output more energy.

The Technical Details

Solar trackers themselves can use two main types of technology to track the movement of the sun throughout the day, these include the following:

• Software that follows a pre-programmed map throughout the day.
• Solar sensors that are able to detect the movement of the sun.

Although the latter reacts to the sun in real time, it is less reliable in times of cloud or at dawn when the sun is less visible in the sky.

Types of Solar Trackers

The two major types of solar trackers are categorised based on their ability to move in either a single or dual axis.

Single-axis solar trackers are able to move on a north-south axis.

For example, this means that during the day they will tilt in the direction of the sun from an east to west orientation in order to follow the sun.

The second type of solar tracker is the dual-axis type, which are able to move in two orientations.

For example, one axis will work as above, but the second axis has a east-west orientation enabling the solar panels to change the angle north to south.

This enables the solar panels to maximise output during different seasons, for example, when the sun angle changes relative to the solar panels due to the time of year.

Are Solar Trackers Worth It?

For commercial ground mounted solar arrays, there is no doubt that a solar tracker is well worth the investment.

In terms of numbers, installing a solar tracker with a single axis can increase output by as much as 25%.

Installing a solar tracker with dual axis can increase output up to an additional 10%.

However, solar trackers are not used in residential solar panel installs.

Why not?

Solar trackers are extremely heavy and are not designed or suitable for domestic roofs.

They are also extremely costly and since they have moving parts and use software, they take a lot of maintenance.

For this reason, solar trackers are usually only employed in large commercial solar farms where the added expense makes financial sense.

FAQ: Solar Trackers in the UK

1. What is a solar tracker?

A solar tracker is a device that orients a solar panel toward the sun. By tracking the path of the sun throughout the day, solar trackers can increase the amount of solar energy that the panels receive, potentially boosting their efficiency and the amount of electricity generated.

2. Are there different types of solar trackers?

Yes, there are primarily two types of solar trackers: single-axis and dual-axis. Single-axis trackers move in one direction, usually from east to west, following the sun’s path. Dual-axis trackers add another dimension, adjusting both east-west and north-south, which allows them to capture even more sunlight as the sun’s elevation changes with seasons.

3. How much more efficient are solar trackers compared to fixed solar panels?

Solar trackers can increase the energy output of solar panels by 10% to 25% depending on the geographic location and the type of tracker used. Dual-axis trackers generally provide the highest efficiency boost, especially in higher latitudes like those found in the UK.

4. What are the benefits of installing a solar tracker in the UK?

The main benefit is increased energy production. This means more electricity is generated, which can significantly reduce your electricity bills and increase savings. Additionally, if you are participating in a scheme like the Smart Export Guarantee (SEG), more energy production can lead to higher payments for exported electricity.

5. Are solar trackers worth the extra investment?

Solar trackers do cost more than fixed installations, both upfront and in terms of maintenance. The decision to invest in a tracker should consider the potential increase in energy output versus the additional cost. For many, the payback period will be longer, but the overall returns over the lifespan of the system could be higher.

6. Can solar trackers be retrofitted to an existing solar panel installation?

Yes, it is possible to retrofit solar trackers to existing solar panel systems. However, it involves significant alterations and additional costs. It’s crucial to consult with a professional to ensure that your current system can support a tracker both structurally and in terms of compatibility.

7. What maintenance do solar trackers require?

Solar trackers require more maintenance than fixed solar panel systems because they have moving parts. Regular maintenance tasks include checking and lubricating the moving parts, ensuring that the motors and gears are functioning correctly, and replacing worn-out components.

8. How do weather conditions affect solar trackers?

Solar trackers are designed to withstand typical weather conditions, including rain and wind. However, extreme weather conditions like heavy snow or very high winds could pose challenges. Most modern trackers come with sensors that stow the panels in a flat position to minimise wind resistance and protect them from damage in such conditions.

9. What should I look for in a solar tracker manufacturer or installer?

Look for companies with expertise in solar tracking systems and a good track record of installations in the UK. Check their certifications and whether their products are tested to meet local standards and conditions. It’s also helpful to read reviews and testimonials from previous customers.

10. Are there any government incentives for using solar trackers in the UK?

While there are no specific incentives for using solar trackers, any increase in solar energy production through their use will benefit from existing schemes such as the Smart Export Guarantee (SEG), where you are paid for the electricity you export back to the grid.

Solar trackers can be a great addition to your solar energy system, especially if you are looking to maximise your energy production. They represent a more significant initial investment and require more maintenance, but the potential for higher energy output and longer-term savings can make them worthwhile for many users in the UK.