Actionable values hidden inside the Drone Data: Solar Inspection

Solar energy is a sustainable solution to worldwide energy challenges. Photovoltaic (PV) solar cells convert sunlight directly into electricity without any fuel, moving mechanical parts or waste generation.

PV modules are exposed to harsh environmental conditions which can make them vulnerable to various defects that can lead to significant yield losses. Hence periodic inspections are necessary in order to maintain efficiency at optimal levels. Commonly known PV defects include Mismatches, cracks, delamination, snail trails and soiling.

Manual inspection methods are:

  • IV curve tracing
  • Visual inspection
  • Electroluminescence
  • IR thermography

Why use UAV for Solar Inspection?

Where manual inspection techniques can take hours and days for a small site. UAV thermal imaging of hundreds of acres can be done in a single day. Aerial thermal imaging can be used to inspect large areas and pinpoint solar panel problems.

An aerial RGB camera can help detect problems like soiling, shading, bird excrement and etc. The thermal camera can identify these issues as electrical anomalies and hence they are paired together to accurately detect defects in the field. The thermal cameras are also called long-wave infrared cameras detect the infrared band of the electromagnetic spectrum they can allow us to see even in total darkness, and also through fog and smoke hence they accurately measure temperature and detect anomalies.

There are some factors that must be taken into consideration when on-field like environmental conditions, ideal conditions for drone thermal imaging of solar inspection will be clear skies and low wind speed and the ideal time for the inspection is late morning to early afternoon.

Using the results of a drone inspection a PV testing technician can more efficiently execute manual electrical testing on only the impaired PV panels.                                                                       

Advantages of drones over manual inspection methods

1.      More accuracy and less chances of overlooking anomalies : Manual instructions are time taking, labor intensive and leave a room for error. Also the results are impacted by the environmental conditions and technical experience of the technician.

Using drones every individual module can be analyzed at a cell level and there is no chance of overlooking the anomalies.

2.      Time reduction: Drones can reduce the time in the field by 90%. There is no need for a big team to inspect a small area. Using drones technicians are quickly able to prioritize anomalies by the level of severity and make appropriate repairs.

3.      Site safety: In the case of manual inspection the solar farm has to operate at its maximum capacity and technicians have to work with open circuits which is extremely dangerous and puts them to risk.  Drones eliminate most of the unnecessary work by pinpointing the faults.

4.      Reduced costs: Drone solar inspection means are conducted 10 times faster and there is no need for a big team of highly skilled technicians, hence labor costs are saved.

5.      Maximizing productivity: Due to quick detection of anomalies there is less delay in repairs and therefore Drone Technology maximizes productivity of solar farms.