My MacBook pro late 2011 15" has 800% usage with kernel_task
So after long time of surfing the web i found this which fixed the issue:


Reboot into recovery mode (Command + R on boot prior to startup chime), select Utilities/Terminal, csrutil disable  (repeat process, use csrutil enable after removing the file), reboot.
Go to About this mac under the apple in the upper left and click on More info
Click on system report
make a note of what it says after Model Identifier (MacBookPro8,2 is mine).
From the Root drive (not home folder): – System  Library – Extensions – IOPlatformPluginFamily.kext (alt-click/View Contents) – Plugins – ACPI_SMC_PlatformPlugin.kext – View Contents – Resources -– find the name from step 3 and move it to a folder that you can find again if needed.
Restart and you’re done (other than enabling SIP).


I can use my Mac again!