How Drones are Driving Down Inspection Costs in the Solar Industry

Recently there’s been a tremendous push towards renewable energy. In 2021 renewable energy generation is set to grow by 8% — which is the highest growth rate in a single year since the 1970s. Renewable energy makes up 29% of the world’s energy generation; out of this Solar energy produces roughly 20% and is forecasted to grow. So how can we push and empower this growth even further? A straightforward answer, of course, would be to reduce the costs associated with solar energy — a mission drones are currently being used to achieve.

Solar panels manufactured today are built to last for decades. While they may remain operational the entire time, the panels don’t maintain the same level of operational efficiency throughout. And this is only natural; repeat and constant exposure to the environment causes degradation and faults to develop, which drops the panel’s production capacity. However, through routine inspection and maintenance, solar farms can ensure performance integrity and energy production — But, the traditional method of solar inspections is slow, labour intensive, and expensive.

Inspecting Solar Farms on Foot

Any form of ground-based inspection is strenuous — this is especially true for solar inspection. Inspectors walk along rows of solar panels besieged by the hot sun from above and its reflection from panels below. Considering that most industrial-sized solar farms are a few square kilometers large; it becomes painfully apparent why the traditional solar inspection method is labour intensive.

When either faults or degradations impede a panel’s producing capabilities, the unused energy is released in the form of heat. And so, thermal sensors become an integral tool in assessing solar panels. Traditionally, inspectors on foot set out with handheld thermal sensors, which they use to collect data.

The reflection of the sun we mentioned before? This is a problem during data collection as well. The reflecting light can skew recordings and make inspections yield inaccurate results. Using handheld sensors, you have limited options when it comes to mitigating reflections. Inspectors have limited mobility and may not be able to change angles sufficiently enough to avoid capturing the reflection. Alternatively, you could be more selective with the inspection time, but this would drag out an already lengthy process.

After the long grueling hours under the sun, the work is still far from over. The data collected by multiple teams need to be compiled and analyzed. Inspectors also have to manually keep track of faults’ locations to go back and perform maintenance which adds to the team’s workload. The limited visibility combined with human error can lead to faults going undetected, reducing the solar farm’s overall output and efficiency.

Solar panels degrade over time and that is inevitable. The German Fraunhofer Institute found that PID (Potential Induced Degradation) can cause solar farms to lose upwards of 30% of their production capacity. Routine inspections are integral to keeping solar farms efficient, effective and performing optimally. But, the traditional inspection methods are expensive, time-intensive, and ineffective.

Making Solar Panel Inspections Safer, Faster and Cost-effective using Drones

The growing interest and demand in renewable energy — specifically solar energy calls for a better inspection solution. One that makes solar more accessible. The ideal solution would be:

Scalable

Meeting just the current needs is insufficient; a sustainable solution would have the capability to scale up and sustain future requirements.

Repeatable

Inspection operations are often repeated on a regular basis. Having an easily repeatable solution that provides consistent and historical data is critical.

Fast & Efficient

Industrial solar farms usually house tens of thousands of panels that require inspecting. So you’d need a tech that can cover large parcels of land seamlessly.

Cost-effective

The traditional inspections were expensive, both in time and manpower. Solar farms would benefit from a faster and reduced labour requirement which drives down the cost.

Finding a solution that checks all the boxes may seem challenging — but other industries have been using drones to fulfill the same requirements with great success. Drones equipped with thermal sensors can capture data of entire farms in just hours.

We found that on average, an inspector on foot can inspect about 60 – 100 panels in a day. Using a drone, we improved that number to 32,000 – 56,000 panels in a day; that’s around 55,900% increase in inspection efficiency!!

Apart from efficiency gains, drone inspection also drastically cut down on the required manpower and workload. Drones enable you to inspect around 32,000 – 56,000 panels in a day — to scale up, simply add more drones. Finally, you only really need to plot a flight plan once; for subsequent inspections, the drone can use the same plan to consistently repeat inspections.

Drones offer an efficient, cost-effective and scalable solar inspection solution. Drones help reduce the cost of maintaining and running solar farms while empowering organizations with data that can be used to improve energy production efficiency.

Inspecting around 900,000 Solar Panels in 5 Days

The Muhammed bin Rashid Al Maktoum Solar Park is a massive 300- megawatt farm. The farm stretches across a 3.4 sqkm area with over 900,000 panels. Inspecting this solar farm used to be a long and laborious operation, with teams of workers combing through the colossal solar farm manually. This usually took about two months to complete from start to finish — to make this process more efficient FEDS Drone-powered Solutions were brought on.

Inspecting solar panels on foot is challenging; inspectors walk between solar panels in the blistering heat taking readings via handheld thermal sensors. This method of solar farm inspection is labour intensive, time-consuming, and inefficient. Keeping in mind that inspecting this entire park took about two months, repeating this yearly or even more frequently is a huge time sink.

The slower turnaround time of the traditional inspection methods means the solar farm operates on a lower productivity level for longer. Apart from the direct drop in energy production efficiency caused by the defects, damaged panels can also act as a load that holds in energy instead of generating it. Therefore, not being able to diagnose these faults in a timely manner greatly affects the overall production efficiency of the solar power plant.

To make this inspection faster and more efficient FEDS chose to use DJI’s M-300 with the H20T payload. Using drones, FEDS were able to collect multi-faceted data enabling the engineers to perform visual and thermal inspections from the output of a single flight. However still, covering a 3.4 sqkm plant is no easy task. It required meticulous planning to optimize and execute effectively.

The final plan was a three-team effort. With their own drone and backup drone, each team would tackle segments of the farm at a time. Segmenting the farm into multiple parts improved safety and coordination among the pilots, it ensured that the drones wouldn’t be in close proximity with each other and protected the drones from being overworked.

Flying at an altitude of 40 m the FEDS pilots covered the entire park in just five days. Through drones, FEDS were able to turn a two-month-long operation into just five days. The result is being able to detect, identify faults and issues quickly, which can then be followed by maintenance drives. The improved efficiency and cost-effectiveness of drone-powered solar panel inspections empower farms to perform at maximum capacity. Are you interested in making your solar farm more competitive? Get in touch with us.

About the author

Niiveth Mani

Niiveth Mani