Power signature
A power signature was a distinctive energy emission unique to technologies of individual space-faring species.

In 2151, Sub-Commander T'Pol and Shran analyzed the power signature of an approaching vessel, and was able to determine it belonged to the same species who had murdered the crew of an Axanar cargo ship, by comparing the power signature to the bio-pump that was being used to drain the murdered crew of triglobulin. ()

In 2154, the crew of  was able to determine that an apparent Tellarite cruiser that attacked an Andorian ship, and an Andorian ship that attacked Enterprise, were in fact, the same ship, by analyzing its power signature. ()

When the  approached the star system where Terralysium was located, the didn't detect any power signatures or warp signatures of any kind in the area. ()

In 2373, the power signatures of 15 Borg cubes were terminated. It was revealed that they had all been destroyed by a Species 8472 bio-ship. ()

See also 
 Warp signature
Energy
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