[sudosysgen]

This is just completely false. You have no idea what the actual max power consumption of an MBA is.

15W is it's TDP, and various companies release chips that run at triple their TDP - including repeated by Apple in the past. Saying it's never going to exceed it's TDP is just blatantly ridiculous, and Phoronix were completely right in treating it as a useless number (which it is).

The only reliable way to measure power draw is either to monitor the exact voltages and amperages on each power lane - which is not made available by Apple - or wire into the motherboard. Anything else is not serious, least of all taxing the TDP to its word.