Semtech touts LoRa for utility-scale solar monitoring

Semtech said LoRa wireless technology is increasingly being used to monitor solar farm equipment beyond panels, particularly trackers, inverters and cleaning robots at utility-scale sites.

At large solar projects, the main challenge is often not the panels themselves but the systems that keep output steady. Trackers adjust panel position, inverters convert direct current into alternating current, and cleaning robots remove dust and debris that can reduce generation between maintenance visits.

Semtech argued that older monitoring methods based on wired links such as RS485 become harder to justify as projects spread across hundreds of hectares. Trenching, conduit installation and fault-finding add cost and complexity, especially when operators need data from thousands of devices across a single site.

It presented LoRa as a long-range wireless option for this monitoring layer, saying a private LoRa network can cover utility-scale solar farms without the recurring charges of cellular connections and without relying on local mobile coverage in remote areas.

Inverter challenge

Inverters are one of the clearest examples of the monitoring problem. String inverters, central inverters and microinverters all perform the same core task, but each can suffer heat-related efficiency losses and component wear. Operators need regular data collection to detect faults early.

According to Semtech, wired connections still make sense when the number of inverters is small and fixed. At utility scale, however, adding conduit and cabling to every unit can raise capital costs and make later expansion harder.

The company also pointed to retrofit approaches that add wireless data collection to existing photovoltaic storage equipment. One example was a data acquisition stick based on its LoRa Connect SX1262, which plugs into inverter infrastructure and sends generation, voltage and current readings to cloud software.

Semtech said the device can run on a private LoRa network with as many as 100 nodes per gateway and connect onward through MQTT, Modbus and TCP or UDP.

Tracker systems

Trackers present a different operational problem because they are mechanical systems spread across wide areas and exposed to wind, terrain shifts and wear over time. Single-axis trackers are now common in large solar plants because they can increase output compared with fixed-tilt systems, but failures in motors, actuators and gearboxes can cut production or leave rows exposed during storms.

Semtech said a 250MW project may contain 5,000 to 10,000 tracker rows, each requiring data on angle, motor status and fault conditions. In many rural parts of India, the Middle East, Central Asia, and remote areas of North America and Europe, cellular coverage may be unreliable or too costly at that scale, it added.

One tracker manufacturer highlighted by Semtech was PV Hardware, a Spanish original equipment manufacturer with more than 650 projects worldwide. Its system uses integrated anemometers to trigger stow commands across tracker rows via LoRaWAN when wind speeds pass a threshold.

PV Hardware has deployed several hundred thousand trackers operating on LoRaWAN worldwide, including networks managing as many as 40,000 devices, according to Semtech.

Mobile robots

Cleaning robots pose another monitoring challenge because they are mobile and battery-powered. Unlike trackers or inverters, they cannot easily be tied to a fixed wired backbone, yet operators still need data on battery charge, position, cleaning-cycle completion and mechanical faults.

Semtech argued that this makes low-power wide-area wireless attractive, because one gateway can cover the site while the robot moves between panel rows. Lower transmit current also helps limit the impact on a robot's battery budget, it said.

The broader case is that utility-scale solar monitoring increasingly requires wide coverage, low power consumption and freedom from dense local network infrastructure. Semtech contrasted LoRa with shorter-range options such as Zigbee and Wi-Fi, arguing that they need far more access points across open terrain.

Market pressure

The backdrop is a growing solar operations and maintenance market. Semtech said the sector is projected to reach USD $9.48 billion by 2025 as operators shift from reactive to predictive maintenance across larger fleets.

It also pointed to continued growth in utility-scale installations in India, China, the Middle East and the Americas. India was singled out as a market where renewable energy expansion is driving demand for monitoring systems that can scale without the cost of widespread wired sensor infrastructure.

For Semtech, the commercial argument reflects a shift already under way in the field. Several original equipment manufacturers have independently adopted LoRa for different solar monitoring products, it said, citing common factors such as site scale, remote locations and the need to manage large numbers of devices without recurring network fees.

Private LoRa networks can be built using certified gateways, network servers and device hardware from the wider LoRaWAN ecosystem, Semtech said, giving equipment makers a standard route to deployment rather than forcing them to rely on proprietary wireless systems.

In Semtech's view, the question for manufacturers of tracker controllers, inverter monitoring systems and robot coordination tools is no longer whether to add wireless monitoring, but which wireless standard best fits the terrain, power limits and geography of utility-scale solar farms.