The Earth isn’t doing too well – mainly because of humans - and more specifically because of our reliance on fossil fuels for powering our lives. There has been a call for alternative renewable energy solutions and with nearly a 4% percent global share energy production in 2021,solar energy has emerged as a frontrunner.

Usage of solar energy at small scale through solar cookers, water heaters and even setups for powering homes has an advantage from an environmental standpoint. Even more importantly, the economic implications are huge. Powering entire cities through solar energy would greatly benefit the environment while costing only a fraction of what it costs to run a city currently. However, to do so, a much larger infrastructure is required.

How large? India’s largest solar field, spans over 14,000 acres and has a capacity of nearly 2200 MW – enough to power nearly 1 million houses. Although it covers a much larger geographical area[RV2]  than any coal power plant, no lives are risked in mining coal and managing the power plant itself. However, what does become a problem on such a scale is maintenance.

Over time, solar panels can face multiple issues as a result of high voltages, cracks, moisture, debris and wildlife and vegetation. If not addressed these can cause major losses in the energy supply.

EL testing is a handy technique to identify defective cells. This test makes use of a property called electroluminescence -when current passes through a solar cell, it emits radiations which can be picked up by special cameras such as NIR (near-Infrared) cameras. The radiation from a defective cell is either non-existent or of a lower intensity and can easily be identified.

Thermal imaging is another useful piece of technology that can drastically speed up solar field inspections. Defective solar cells are a lot hotter than functioning solar cells, and the images obtained from thermal cameras depict the temperature differences very clearly.

However, using these techniques from the ground isn’t feasible. A plant producing just 1 MW of power would have nearly 5000 panels and covering hundreds of acres in a full-scale solar farm (with capacities of well over 100MW) on foot is tedious, uneconomical, manpower intensive and error-prone –in general, a bad idea. One will have to identify vantage points to employ their cameras, which may not always be feasible. Besides the sheer amount of manual work, the people involved could suffer from exhaustion and dehydration .

Drones could well hold the key to faster and more detailed inspections. Drones equipped with thermal cameras can freely move over the field and ensure proper inspection of every single panel. After configuring the area to be inspected on the ground control station, an optimal flight path is calculated. The drone takes off and automatically takes pictures of the landscape to ensure that a highly accurate heat map of the area can be obtained. From the obtained heat map, every single malfunctioning solar panel can be identified, including the type of failure as well, enabling appropriate allocation of resources for fixing them.

While using drones for inspections of solar fields, one must keep in mind the kind of panels used – such as monocrystalline, polycrystalline or thin film. The type of solar panel determines the optimum height at which a drone must fly – but the lower a droneflies, the longer the inspection takes. Inspections are also hindered by the time of day and the luminescence at that time – marginally cloudy days can quickly halt inspections.

Time spent in inspection of solar fields is cutdown drastically if drones are employed. Quadcopters such as the UMT Sparrow PPK by UrbanMatrix Technologies can provide highly accurate heat maps of areas of nearly 200 acres in a single day, flying at just 40m above the panels. Mapping even the largest solar farms with just a single drone would take a couple of months, while it would take many years to accomplish it on foot with multiple teams on ground. They have also simplified drone launches through the development of a Ground control station called the UMT Launch Pad which enables configuration of flights with just a few clicks on a touch screen. With images obtained from the camera and location data logged by the GPS tracker, identification of the faulty solar panels can be done at leisure.

Drones are a one-time investment and grant the power of inspections for multiple years. With simplified launch systems like the UMT Launch Pad from UrbanMatrix, deploying drones regularly does not require highly trained professionals. With regular checks at your disposal, running highly efficient solar farms to power the future is one BIG STEP closer.