Thermal imaging technology from FLIR is being used in surveillance applications at unmanned solar farms in South Africa.

Tenesol, a SunPower company set up two new solar farms in the Northern Cape Province of South Africa in 2012. The two ground-mounted solar power projects add up to 33 megawatts (MW) in capacity. To protect its valuable solar panel assets against unwanted intruders, Tenesol called upon security specialist TeleEye, which relies on thermal imaging technology for surveillance applications. 

Solar power plants are unmanned sites and require real-time monitoring day and night in order to efficiently deter unwanted intruders and prevent vandalism or terrorist attacks. TeleEye South Africa, a division of Hong Kong based company TeleEye, has many years of experience in securing public utilities sites with their solutions enabling 24/7 standalone and remote operation with real-time monitoring and recording. TeleEye has been a strategic distributor of FLIR thermal cameras since 2010.

For the two solar plants, TeleEye, along with systems integration partner, Stallion Security provided Tenesol with a complete perimeter surveillance solution consisting of thermal cameras, video analytics and alarm management. The two solar plants have perimeters of 5km and 8km, and have been secured with thermal imaging cameras from FLIR Systems and electric fencing. TeleEye video analytics seamlessly integrates with the FLIR thermal imaging security cameras and is able to generate a wide range of alerts for intrusion detection applications.

Philip Smerkovitz, Managing Director at TeleEye South Africa, explains that FLIR thermal cameras deliver very accurate optics and image quality along with robustness, which is an important factor in the harsh temperatures of the sites they monitor. The two solar farms are located in South Africa’s Karoo desert where daytime temperatures of 40°C in summer are not uncommon. 

FLIR’s experience from mission-critical systems is invaluable here, because the company has years of built-up expertise in the development of robust technology, which can withstand extreme environments and extreme heat.

FLIR thermal cameras allow monitoring day and night. Without any additional lighting, it is possible to detect intruders approaching the perimeter at night. The thermal camera’s ability to see in bright sunlight conditions was also important because sunlight can obviously be very bright in the Karoo desert. Thermal cameras are not hampered by brightness, and can provide a clear image even if they are directed towards the sun. Glare from the sun may blind conventional video cameras, effectively hiding vehicles, people and animals but thermal cameras need no light to operate, can ignore this glare, and will only respond to the heat signatures they detect. 

In comparison to traditional video cameras, thermal imaging cameras can cover a larger viewing distance, which means that fewer cameras are needed to efficiently monitor the perimeter. With thermal cameras, there’s no need to invest in or maintain expensive lighting infrastructure. For these two solar parks, 5 and 11 thermal imaging cameras were installed for the 5km and 8km perimeters respectively. TeleEye used different configurations of the SR series, with different lenses in order to efficiently monitor the odd shaped perimeter. 

TeleEye was responsible for the entire specification of the surveillance project, including the definition of the camera technology, video analytics and alarm management. In order to calculate the correct camera viewing distances, TeleEye used FLIR Raven software, the free thermal security site planning tool, which allows the user to conveniently display both range and location for each camera specified. The software shows the area of detection coverage, allowing the user to plan the placement of the cameras.