Although this example uses rudimentary technology available to us today, it illustrates some basic points of energy loss through infrared radiation - MIR energy wastage that even efficient alien technologies will generate.
Exacerbating the Fermi Paradox?
Using WISE data, the researchers have performed a preliminary ("zeroth order") G-HAT survey of galaxies to see if they generate excessive quantities of MIR radiation. But they turned up empty handed, which may, at first, appear to only exacerbate the Fermi Paradox: "(W)e show, for the first time, that Kardashev Type III civilizations (as Kardashev originally defined them) are very rare in the local universe."
ANALYSIS: Alien 'Star Engine' Detectable in Exoplanet Data?
This first null result doesn't prove that Type III civilizations don't exist, it just places a lower boundary on how many of these advanced civilizations populate nearby galaxies... or it illustrates a limitation of our instrumental capabilities.
To improve on this result, further analysis of survey data is needed. Also, the researchers identify possible sources of MIR radiation that could be misinterpreted as heat waste from a civilization, such as dusty stars generating excessive MIR radiation.