About 1 month ago, my MacBook suddenly started running really slow with the fans making lots of noise. Before that I never had any similar problems, it's just like suddenly something happened and it started getting worse ever since. I have a MacBook Air 11'' from early 2014, more specs below.
Also, I have the latest update of macOS Mojave version 10.14.2.
Basically the problem Is that as soon as I turn on the macbook, the fans start making lots of noise. The computer is overall really slow, and even if I just have one window with safari open, it still runs at a really slow rate. Doing basic things such as clicking on buttons, closing windows and opening applications can take a really long time to do. I checked the CPU usage, and it looks like this:
This seemed really weird, as I at first couldn't find any system process taking up that much of the CPU, but later I started up the activity monitor again and I saw something called kernel_task, maybe something that's causing my problems?
Before taking the screenshot above I reset my entire macbook. That is to say I deleted the hard drive and created a new one, and then I reinstalled macOS, so I have no third party programs installed whatsoever, and there is nothing taking up hardrive space, besides the default programs etc.
I've also tried starting the Mac in safe mode, but the problem still persists.
Help is much appreciated, I'm really desperate since this is the only computer I own and I really need to get this fixed.