The global solar tracker market has seen massive growth now that the world is moving towards renewable energy. To give you an idea of the scope of growth, according to the Future Business Insights industry reports, the solar tracker market size was valued at USD 7.88 billion in 2023 and is projected to grow from USD 8.78 billion in 2024 to USD 25.24 billion by 2032. A good 56% of this share in 2023 is in North America. As this growth occurs, we are also seeing an increase in the use of wireless radio technologies to replace wired solutions in large scale solar field installations. Therefore, there are key considerations companies need to consider for a wireless large-scale solar tracker installation. We will share these considerations with you today!
Wired versus Wireless:
In most modern large-scale solar tracker installations, you might find several hundreds of thousands of solar panels in a single installation site which need tracker optimizations to generate energy in an optimal and cost efficient manner. In these installations, wired solutions are still the norm over wireless technologies, however, wireless technologies are starting to gain major traction, offering numerous benefits for such installations.
Wired cabling solutions pose several challenges to your installation including susceptibility to lightning strikes, ground loops, and other wear and tear issues which can fragment communication if a cable connecting multiple solar trackers fails. On top of that, the costs involved with cable repairs and replacements are substantial and quite labor-intensive.
Wireless solar tracker systems are growing in interest because they provide installation flexibility, easier maintenance, and effortless commissioning for quick rollouts, thus, creating significant cost savings and reducing the manpower required for an optimized solar tracking installation. These advantages are the main driving force for the increased adoption of wireless solution, especially today where demand has risen significantly for seamless and efficient system deployments.
Wireless Technologies For Solar Tracker Installations:
There are various wireless technologies available which have been popularized in the solar tracking market today offering their own unique benefits to fit the specific needs of each solar tracker installer. A few of these technologies include Radiocrafts’ RIIM Sub-GHz mesh, ZigBee, Wi-Sun, and LoRa. Let’s take a deep dive into these technologies and highlight the main benefits and challenges each solution offers for the solar tracking segment.
Wireless Technology Comparison: RIIM vs ZigBee vs Wi-Sun vs LoRa
RIIM is a long range Sub-GHz mesh protocol optimized for control applications. Unlike the previous technologies mentioned, RIIM is a proprietary technology that allows it to be optimized in a multitude of ways to meet the unique requirements of each solar tracking installation. Why is this important? Because each solar tracking installer has unique needs for their installation, for example, some may prioritize the speed at which the nodes join the network, while others prioritize low latency or the ability to connect as many devices to a single gateway as possible. RIIM’s network settings can be customized to adhere to these specific needs. After years of working with leading solar tracker companies globally, we have understood the needs of the market and have tweaked our RIIM solution to follow the market trends and our customers’ shared desires. For example, one ground-breaking feature developed for RIIM is to control the solar trackers to quickly move all solar panels in the network into a safe position in less than 1 second during events of high winds or hailstorms. This state-of-the-art feature puts RIIM on top as the technology that offers the industry’s fastest safe position capabilities. This is possible because RIIM is time-synchronized, meaning we can combine LPWAN timeslots for safe position with many high-data-rate timeslots for tracker status polling and over-the-air updates. In addition, in Europe, the LPWAN timeslot can be at 868 MHz allowing for 500mW output power. This means that compared to high-data-rate timeslots such as 2.4GHz, the sensitivity in LPWAN slots allows for 2.5x the range at 915 MHz and 4.5x the range at 868 MHz due to the higher output power. Furthermore, the messages are also sent in 3 consecutive LPWAN timeslots increasing the probability to be received, and hence, increasing the reliability.
Additional unique benefits of the RIIM Sub-GHz mesh solution for wireless solar tracker systems include:
- Simplify your installation and reduce cabling costs significantly with up to a few thousand solar trackers per gateway point.
- Cover an entire solar field, including areas with uneven terrain, with Sub-GHz mesh which offers long range and solid penetration properties through solar tracker beams and reduced panel reflections.
- Operate several RIIM mesh networks in close proximity to each other with minimal data loss at a reliability rate of 99.99% successful packets delivered.
- Take advantage of leading low latency communication between solar trackers and the controller
- Send fast acting updates of critical solar tracker parameters to your entire network through efficient over-the-air updates which works in under 3 minutes.
ZigBee is a consumer-focused, low-power wireless protocol that operates on the 2.4 GHz frequency band. In consumer-focused wireless applications such as home automation and wearables, 2.4 GHz has seen huge success. However, for applications like solar tracking which require long range and reliable scalability, a 2.4 GHz solution is not ideal. Higher frequencies support higher data rates, but at the trade-off of range, and data collection reliability due to poor radio penetration through tracker metal beams and more reflections off the solar panels. Higher frequencies are also more vulnerable to weather interference and which means ZigBee at 2.4 GHz can struggle in a large-scale solar field installation. In addition, ZigBee lacks support for frequency hopping and other important features designed to increase the reliability and scalability of your large-scale solar tracking installation which are implemented by many of the other meshing radio technologies mentioned above. In summary, while ZigBee is effective for consumer applications due to the high data rates, the limited range, lower reliability, and less efficient scalability make it a less viable choice for large industrial solar tracking installations.
Wi-Sun is an established standards-based, Sub-GHz wireless mesh networking protocol designed for large-scale industrial IoT applications. Unlike the other solutions mentioned in this list, Wi-SUN is optimized dynamic environments with moving devices. This is mostly because Wi-SUN uses unsynchronized channel hopping which is optimized for devices in motion. In static environments like in a solar tracking installation, this dynamic optimization means Wi-Sun cannot rely on time synchronization to coordinate data transmissions and avoid interference. Therefore, Wi-SUN trades off static reliability for dynamic flexibility. As a result, Wi-SUN does not achieve the data reliability requirements needed from a solar tracker installation. Finally, as a standards-based protocol, Wi-SUN, much like ZigBee and LoRa, cannot be easily tweaked or tailored to meet the specific requirements of different solar tracker installers. In summary, while Wi-SUN provides flexibility for dynamic installations, the lower reliability and limited customization possibilities make it sub-optimal for industrial solar tracking installations.
LoRa is a low-power, wide area protocol well suited for applications with low data rate requirements and infrequent communication. LoRa supports extremely long range for but faces limitations in large-scale industrial applications which require a higher data capacity for continuous monitoring and control. In addition, LoRa lacks time-synchronization for frequency hopping making it more susceptible to data packet losses and radio interference. This results in a reduced amount of data transmission reliability as you scale the number of devices in the network. Therefore, to cover a large solar tracker installation, you would need multiple LoRa networks with fewer devices per network operating in close proximity to each other. This increase costs and complexity significantly due to the need for a larger number of gateways in the system. LoRa also has severely limited downlink communication for control purposes, for example, for over-the-air updates. The larger the network, the more limitations you see with downlink communication. In summary, LoRa is well-suited for low-power, long range applications that require infrequent data transmissions. The limited data rate, reliability as you scale up devices, and lack of effective downlink communication for control aspects makes it a less suited for complex solar tracking applications.
What To Take Away From This?
In a growing market like solar tracking, it is important to make the best decisions for your installation to take a competitive advantage early on. To achieve this, companies need to have a good understanding of the market trends. One of the main advancements in the solar tracking market to-date is the move from wired to wireless technologies to improve cost savings and increase the efficiency of the solar tracking systems. However, choosing the correct wireless technology can be a challenge as there are many options offering various different benefits. On the one hand, ZigBee, Wi-SUN, and LoRa are standards-based solutions so there is an ecosystem around these solutions with many vendors to choose from. However, the compromise is that the out-of-the-box features offered and lack of customization possibilities make them suboptimal solutions for solar tracking installations. RIIM on the other hand, is a proprietary solution which poses it’s own challenges but has been designed specifically to fit the solar tracker market requirements and can be customized to fit any specific customer needs.