When I first noticed the issue I made sure that my home network was listed first and pruned out pretty much everything else except for the network at my brother's and parents'.



Nope. But since noticing the issue I've added a faster drive and that hasn't helped.



It's only supposed to do this for zero power sleep (what's called hibernation in Windows world). That's supposed to be triggered automatically when the battery level is very low. Have things changed in the past year so that this is happening all the time?



Loads of space free on the new drive and since migrating it should have a pretty large contiguous chunk.

Thanks for the hibernation tips, I'll take a look.



Battery is at 354 or so cycles which is low for the supposed 1000 cycle life of this battery. At the 1000 cycle count it's still supposed to have plenty of juice left, just reduced from what it was originally. I'm also sure the video mode is set to the conservative lower power setting - I double checked this a few times and I always keep it set that way. Battery status says "normal." It used to show over 7 hours remaining but I never see a time anywhere close to that anymore.

Will take a look at that gfx switching tool as well. It would be strange if the System Prefs wasn't showing the correct setting - and it would explain the reduced battery life, that's for sure.

I've done all the steps you mention at the end, including the SMC reset a few months ago. No change. Well, that is to say, I did them due to issue with CPU usage and fan spin-up, probably before I noticed that battery life was greatly diminished. It may be that the diminished battery issues only happened after the SMC shenanigans actually.

I also have a number of the Apple proprietary diagnostics tools but I haven't yet dug them out to try them. Only a couple are fit for this machine so I have to look up which disc to use first.

Thanks for the tips, I have a few things to check out.