macOS Big Sur battery drain issue

Welcome, HimVisa, to Apple Support Communities!

You can shutdown or simply use sleep mode (or deeper, like hybrid-sleep), as you wish.

Shutting down will use the least energy, of course.

The deeper the sleep mode, the lower the energy use, as well.

Unfortunately, EarthBased appears to be having trouble getting his MacBook to even go into any sleep mode.

Update: I took my 2017 MacBook Pro 15" with Touch Bar to Genius Bar. After confirming my findings the serial # qualified for extended warranty. I pay $18 for new USB board and Apple covers $496 to fix battery which includes a new keyboard surface side too since battery is sintered to that. Left it at Apple store since parts where not in stock.

I assumed the computer was not going into sleep mode but that was a wrong educated guess.

I’m glad all looks like it will work out for you, EarthBased!

There have been a few cases where the «battery drain issue» was caused by hardware. It sounds like yours falls in that category (though the hardware failure occurred later, and appeared after an update—strange, but, in no wise, impossible).

I hope, in the future, you’ll work on verifying your “educated guess[es]”, or, at least, make it clear when you are only using a guess.

DanielaCervantes wrote:

I have the same exact problem have you done anything to fix it?

Are you trying to ask Apple that question?

Apple is not here. We are only fellow users, like yourself, here.

I have been helping (and trying to help) many users with this issue, around here.

So far, except in those rare cases where there is a hardware issue, the issue is in software, not related to Big Sur: typically background software running on people’s machines.

Have your noticed my messages on this issue, with others, here?

disillusioned2 wrote:

activity monitor says safari is taking 99% of my cpu

This can be quite normal, depending upon what websites you are browsing.

By the way, this indicates 99% of a single CPU core.

How many CPU cores does your system have?

Divide 99% by the total number of CPU cores, and you’ll have the percentage of your total CPU processing capability.

(Note: on my four [4] core Mac mini, I have some processes that I run that come very near to 400% CPU!)

This is not normal. I can have zero websites open and it still happens, and it drains my battery very quickly. Only happens if I have 2 windows open. If I only have 1 open then it goes down to a reasonable 2% cpu.

Why would having 2 windows open (I've tried 2 Private windows vs. 1 of each Private and Not Private) cause this issue?

disillusioned2 wrote:

This is not normal. I can have zero websites open and it still happens, and it drains my battery very quickly. Only happens if I have 2 windows open. If I only have 1 open then it goes down to a reasonable 2% cpu.

Why would having 2 windows open (I've tried 2 Private windows vs. 1 of each Private and Not Private) cause this issue?

Again. It all depends upon what websites are being visited. Is it always Safari?

We have also noticed that have browser extensions—particularly ill behaved ones—can make a huge difference.

Use Activity Monitor, on the CPU tab, with the View set to “All Processes”, rather than the default of “My Processes”, to see what is actually going on.

(Unfortunately, at this time, browser extensions may not show up as separate subprocesses. [It depends upon their implementation.])

Unfortunately, we seem to be talking past each other.

1) I have ZERO websites open. Notta, zilch.. :-)

2) If I have 2 Windows open(with zero websites) I'm over 100% (all Processes)

3) if I close one of the two Windows (with zero websites) the it goes down to 2%.

Not a website discussion what-so-ever.



disillusioned2 wrote:

Unfortunately, we seem to be talking past each other.

1) I have ZERO websites open. Notta, zilch.. :-)

2) If I have 2 Windows open(with zero websites) I'm over 100% (all Processes)

3) if I close one of the two Windows (with zero websites) the it goes down to 2%.

Not a website discussion what-so-ever.

What App are you seeing high CPU usage on, when you «have ZERO websites open. Notta, zilch.. :-)»?

What App are you using when you «have 2 Windows open(with zero websites) I'm over 100% (all Processes)»?

Is that «over 100% (all Processes)» the sum total of all CPU usage, for all processes? Or something else, such as the CPU Usage graph?

fred_logan wrote:

Monterey available 10/25/21. Upgrade yes/no???

If you are still experiencing hi CPU/Power usage, or slow performance (due to excessive background processing); you shouldn’t upgrade until you have resolved all current issues.

Otherwise, if all such issues are fully resolved, you may do as you wish, based upon your own assessment of benefits.

Basically, never expect new Operating Systems (OSs) to resolve issues you may be experiencing.

fred_logan wrote:

I just upgraded[actually, just an update] to version 11.6.1 (20G224), 31% loss of battery power in 1 hour...

It sounds like you haven’t, yet, resolved your power/CPU usage issue.

So, like I already recommended, solve this issue, first, before upgrading to Monterey.

You need to track down the culprit (software), so you can decide what you want to do about it.

No one else can do it for you (unless you want to take your Mac into someone to fix it for you).

If you want, we have already recommended a true test (and a couple of simple, but less definite tests).

What do you want to do about your issue?

Since March the battery/cpu/power issue couldn't be solved by Apple Care & Apple Store. The clean install & battery replacement didn't work either. Same issue after updating to Big Sur 11.6.1. Apple Support told me to upgrade to Monterey, what I did... same problem. So, I probably have to start a new thread called 'macOS Monterey battery drain issue'.

fred_logan wrote:

A clean install was also accomplished by the Apple Store team.

Of course, a «clean install» followed by a restore, prior to any significant testing, is, no longer, a «clean install», for the purpose of said testing.

If the testing was actually performed upon a «clean install», then you have a Hardware Issue, though, apparently, not just the Battery (since that was replaced). There are other Hardware components that can fail, and cause power issues. (Any short circuit will do.)

paomug67 thanks for posting abut your move to Monterey. Yesterday morning on Big Sur my battery (a new battery installed by Apple) drained to 58% in 2 hours. After reading your post I upgraded to Monterey and this morning after roughly 2 hrs on battery I am at 91%. No upgrades to anything else on my MacBook Pro and same applications running.

Today Apple support told me that Big Sur might have installed a new firmware that is responsible for the battery drain.

Does anybody know how to downgrade the firmware (T1, Firmware-Version: 14Y908) ?