The system uses thermoelectric panels; Peltier Plates, see
HERE.
"Adaptiv is an active camouflage technology developed by BAE Systems AB to protect military vehicles from detection by far infrared night vision devices, providing infrared stealth. It consists of an array of hexagonal Peltier plates which can be rapidly heated and cooled to form any desired image, such as of the natural background or of a non-target object. Its goal is to develop Stealth ground vehicles."
See also
HERE.
"When an electric current is passed through a circuit of a thermocouple, heat is evolved at one junction and absorbed at the other junction. This is known as the Peltier Effect. The
Peltier effect is the presence of heating or cooling at an electrified junction of two different conductors and is named after French physicist
Jean Charles Athanase Peltier, who discovered it in 1834.
[7] When a current is made to flow through a junction between two conductors, A and B, heat may be generated or removed at the junction."
cheers,
Robin.