Although there's a lot of good information in that article, (I was reminded I need to install an ad blocker, safari for an hour a day can easily be 50% of my battery usage) I was astounded to not see any mention of bluetooth. I turned that off a month ago and noticed a massive improvement on battery life.
I had turned it on to use my new bluetooth speakers in my truck, but I left it on, and my battery was dropping like a stone. Now I turn it on only when in the truck. It's a bit inconvenient, but has almost doubled my battery life.
