Battery Drain after NVME Upgrade MacBook Air 2015

What I wrote up here was the theory, which I thoroughly studied, before buying an upgrade for a MacBook Pro 15" (Mid 2014).

Meanwhile I bought a Crucial P2 2TB. Compared to the original Apple Samsung SSD 512GB:

• You get ca. 2x the speed (ca. 1300-1400 MB/s instead of ca. 650-700 MB/s for both read/write)
• Without any extra drivers/optimizations power drain in most situations is similar (macOS 11.1 Big Sur with Firmware 429.0.0.0), worse in idle, better at full load, long term I did not test.
• With SsdPmEnabler power efficiency is significantly better! I meanwhile use this for ca. a week and have not experienced any crashes and it properly goes into standby and wakes from it. Hibernation I have yet not tested, because I use my computer almost daily, so it never goes to it.

1) Get the newest firmware, where power management is already better and/or some sleep/wake issues are resolved

a) Either by upgrading to Big Sur (or in Catalina, Mojave the latest security updates) with your original SSD inside

OR

b) Upgrading Boot ROM Version without upgrading to Big Sur​

2) Install tools which significantly lower the idle wattage for 3rd party SSDs

a) SsdPmEnabler

b) NVMeFix plugin inside lilu

c) a+b combined reach an even lower wattage in most cases

That's the short version of a meanwhile 8000+ post long thread in the Macrumors forums (!)

Hey SunRahul,

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