One of the things that the Coronavirus induced lockdown has made me appreciate is the advantages of a big monitor on your home office desk. That, and a laptop that actually has an HDMI port for it. If you’re a Mac user like I am, stuck at home trying to work on an external monitor with your laptop, chances are you don’t want to have your laptop’s screen shining on the periphery of your vision. That’s very distracting. So you probably want to close the lid of your laptop and use the external display as the main monitor, right. Plus you wanna do that without connecting a power adapter all the time. So here’s how you can use a MacBook in clamshell mode without a power adapter.

Why Do MacBooks Not Support This by Default?

Why do we need an entire article on how to do this? Well, turns out, Apple will not let you do that unless you have a power adapter connected to your MacBook. Take a look at the company’s official help document about this. Now when I was getting started with this whole set up, I took Apple’s word for it and kept using my MacBook with the charger connected to it at all times, knowing full well that it will destroy my battery’s health. It did just that, and my battery doesn’t charge anymore. Now I’m stuck using my laptop as a glorified desktop, and with an impossibly throttled CPU to boot.

  • Why Do MacBooks Not Support This by Default?
  • Save Mac Battery by Using It in Clamshell Mode without Power Adapter
  • Using a Third Party App
  • Using Terminal Commands

There are a bunch of terminal commands you can use to disable sleep, and we will discuss those in a later section, but chances are you don’t want to mess with terminal commands and a simple one-click solution is really all you’re looking for.

Now that we know that the issue is that the MacBook goes to sleep on closing the lid even if we have an external display connected to it, the solution is simple. We need to prevent that sleep from happening. But you can’t just use a simple Caffeine-type app to solve this problem. That’s because the hall sensor on your MacBook detects when the lid is closed and just puts it to sleep regardless of everything else.

You must have heard of the app ‘Amphetamine’ which is a hugely popular Mac app that controls sleep states for the Mac based on triggers and what not. While the app originally did not have the capability to solve our problem, it has since been updated and actually can help us get out of this pickle.

  • Now, click on the Amphetamine icon in the menu bar.

  • Install the helper and launch it. Select ‘Closed-Display Mode Fail-Safe’ from the sidebar and click on ‘Install’.

Using Terminal Commands

If you don’t want to use a third party app to get this done, or you just want to play around with Terminal commands and figure things out for yourself, there are some commands that can achieve similar results.

pmset -g | grep hibernatemode

  • Now, run the following commands in the terminal.

sudo pmset -a sleep 0 sudo pmset -a hibernatemode 0 sudo pmset -a disablesleep 1

These commands will disable sleep on your MacBook, and you should be able to use your Mac in clamshell mode without an AC adapter connected.

sudo pmset -a sleep 1 sudo pmset -a hibernatemode <original hibernatemode value | usually 3 on a MacBook> sudo pmset -a disablesleep 0

Use MacBook in Clamshell Mode without AC Adapter, and Save Your Battery Health

I may have knowingly caused my MacBook Pro’s battery to become completely unusable to the point where it doesn’t even charge anymore, but you don’t have to follow in my footsteps. Now that you know how you can use an external display with your MacBook and not have to keep an adapter connected to it all the time, go ahead and set up your work from home desk with your brand new monitor and enjoy working on a bigger screen with more real estate. Oh, and whatever you do, don’t take Apple’s word on things like this. Meanwhile, I’ll go and try to figure out if I should buy the M1 MacBook Air or the M1 MacBook Pro.