I have an M1 Air (Sonoma 14.1.2), which most of the time has a reasonable battery life. However, sometimes it inexplicably drains battery, as shown on the second Friday here where ~27% of the battery is consumed without me ever touching the machine:
Most days, power usage seems proportional to screen-on time (i.e. I am actually using the machine). The battery item in the menu bar claimed no apps were using significant energy.
Here's a similar effect that just happened overnight. I used the Air yesterday evening, but then through the night ~25% was steadily lost.
Looking at the output of pmset -g log, I see there is an almost continuous stream of events being logged, such as this recurring burst of 3 events, repeating every 15 minutes:
2024-01-09 01:31:48 +0000 Assertions PID 22686(com.apple.PassKit.PaymentAuthor) Summary PreventUserIdleSystemSleep "Cancelling Apple Pay transaction" 298:59:49 id:0x0x10000a678 [System: PrevIdle]
2024-01-09 01:31:48 +0000 Assertions PID 22686(com.apple.PassKit.PaymentAuthor) Summary PreventUserIdleSystemSleep "Cancelling Apple Pay transaction" 363:01:24 id:0x0x100009399 [System: PrevIdle]
2024-01-09 01:31:48 +0000 Assertions PID 22686(com.apple.PassKit.PaymentAuthor) Summary PreventUserIdleSystemSleep "Cancelling Apple Pay transaction" 367:45:53 id:0x0x10000916e [System: PrevIdle]
(always the same PID, going back as far as pmset -g log can see - Jan 2nd)
Strangely, after a week, now that particular process is no longer running. That 15 minute interval is probably frequent enough interruptions that the machine was never truly sleeping.
I deliberately leave very little running. For example, I always close Music, Xcode and the simulator, even if it feels like that shouldn't be a requirement. (unless it's been fixed, those dynamic album covers seem to drain power even when Music isn't visible)
Is there a way to get more fine-grained (and preferably historical) energy usage info than is offered by the menu bar?
Update (5 days later)
Focussing on that unexpected and repeating "Cancelling Apple Pay transaction" log message, which crucially is settingPreventUserIdleSystemSleep, it seems likely that is the culprit.
Coincidentally, I used Apple Pay on it again a couple of days ago, and again the drain-without-use happened, and again com.apple.PassKit.PaymentAuthor was "spamming" the logs every 15 minutes. I kill -9'd the process yesterday (regular kill had no effect) and since then there has been close to zero battery drain. I've reported it via https://feedbackassistant.apple.com
This machine gets irregular and light usage. It is rarely rebooted. Maybe the phenomenon is "lost in the noise" for machines that are more heavily used.
