[teilo]

I have exactly the opposite experience. Mojave is substantially easier on the battery of my 15" 2018 MBP than High Sierra was.

One reason (probably not the only reason) is that Mojave is much better at GPU switching, and manages to quickly and fully shut down the discrete GPU once it is no longer being used. In HS, this did not happen. The Radeon would still be drawing power even when, supposedly, only the integrated GPU was supposed to be active.

I'm typing this on battery, and currently drawing between 6-14W while running Firefox. In HS this would be between 20 and 30W.

[fxmc]

How do you measure power consumption on a Mac? I'm using a 15" 2015 MBP with ~4h battery life, even when the battery was new. I'd like to see how the upgrade affects this.

[klohto]

I don't about precise power measuring tools, but I use CoconutBattery which displays what my current drain charge is. I already know what the values are when "idle", so I can compare the new values on Mojave with the ones I remember.

[teilo]

All of this info is available in the system instrumentation, so with the right utility you can see it in real time. I use iStat Menus.