Every day we are presented with thermographic images – in the form of maps in the weather forecast on TV. Other uses in the television cosmos are animal documentaries, for example, to depict the view of a snake. Another area of application is medicine. In industry, thermographs are mainly used for the thermal inspection of buildings, as they can be used to quickly and easily visualize heat losses on walls, heaters, and windows. This technology is used above all in the modernization of existing buildings to detect heat losses. The energy revolution also brings efficiency awareness to society, and before investing in expensive new windows or new roofs, the heat loss should be inspected and the need for such renovations determined. After all, heating systems and hot water preparation are the largest energy consumers in German households.
While we are on the subject of the energy revolution, the thermographic method is also used for inspections and maintenance preparations for solar and photovoltaic systems.
How thermography works
But what’s behind the colorful pictures we see every night in the weather report?
Technically, the cameras used are thermal imaging cameras that can record infrared radiation. The temperature of objects correlates with the infrared radiation they emit. The temperature differences are normally colored to show a difference for humans.
The special feature of so-called radiometric thermographic cameras is not only the image generation but also the possibility of storing the temperature of each individual pixel. Therefore, the resolution of these cameras differs significantly from ordinary RGB cameras – the amount of data each pixel provides is simply much higher.
Application example photovoltaic system – The wavelength counts
Infrared radiation is invisible to the human eye. The infrared range has a wavelength of 700 nm to 1 mm, i.e. 1 million nm (nanometers). This is an enormous range of radiation and therefore the infrared radiation is divided into different ranges, namely into near infrared, short-, medium- and long-wavelength infrared, and far infrared. For medical purposes, both the near infrared (especially in ophthalmology) and the far infrared (stimulation of the nervous and immune system) are used.
For the thermographic representation of PV systems and buildings, a spectrum from 8 nm to 15 nm is used, the long-wavelength infrared. In the shown example picture of a roof photovoltaic system, the temperature differences of the different system components are visible through the thermographic representation. This example comes from our latest partnership with UCAIR, who kindly provided us with this picture.
UAVs and Thermography – the Game Changer for Photovoltaic plant inspections
As you may already see from the example picture, this is an aerial photo. This picture was taken by an UCAIR pilot not costly with a helicopter, but of course with a drone!
The flight plan was previously created by another UCAIR employee with our project management software HORIZON.
Due to our extensive geodata, the project creator could see directly which rules and laws applied at the location and could plan a flight route with just a few clicks. That route was then sent and approved by the authority.
Since HORIZON offers the possibility to share project data with others, the pilot received the flight route within our software. Our software is cloud-based, so that the pilot did not even have to be phisically present in the company. After sharing, he found the flight route directly in his user account.
The thermal data generated during the inspection flight was then loaded into HORIZON by the pilot. This analysis integration is an exclusive feature of our HORIZON Enterprise edition. The responsible thermographer was able to retrieve this data via his account in order to make it available to the corresponding customer in a prepared form. This is also completely possible via our software.
Advantages of integrating HORIZON ENTERPRISE
UCAIR was able to improve its workflow by integrating our software. The possibility of a cloud-based data release gives the company an enormous time advantage, as it enables drone pilots throughout Germany to directly obtain their flight routes. This increases the radius of action of this service provider immensely, as the drone pilots can work decentrally. A further time advantage is created by the fact that the collected data records can be transmitted directly to a thermographer, who can then evaluate them and transmit them to the customer. The reporting can be used again and again for comparison during recurring inspections and thus continuous logging of the plant condition is created.
Advantages of drones for thermography
Obviously, an inspection flight with a drone is cheaper than with a helicopter.
The drone is also cheaper than a thermographer with a handheld device. Compared to a drone, it takes much longer to inspect an entire facility or building, and the thermographer has to be paid for the corresponding time. The larger the plant or building, the greater the time and cost advantage of the drone compared to a thermographer with a handheld device. The data sets generated during the inspection with drones are also more detailed since they can take a better viewing angle from the air than, for example, a thermographer from a ladder. In addition, the danger for the thermographer is reduced because he no longer has to climb roofs. Thanks to the inspection, defects can be detected at an early stage and future maintenance can be anticipated (predictive maintenance).
The French drone manufacturer Parrot recently introduced a drone with a factory-fitted thermal imaging camera. Industry leader DJI has also been offering such a model since the beginning of 2019. This shows that thermography is already an integral part of the drone industry. In the future, more and more models with even better cameras will certainly follow, so that the recording quality will continue to increase and, ideally, the purchase price will continue to fall. With our software solution, we want to help companies to integrate drones into their workflow in order to use their entire potential profitably.
The FlyNex Team