The world of battery extension is stocked with myths and legends. Lower your brightness before sleeping the device, quit every app you aren’t using, turn on single app mode — the list is as long as it is ineffective. Here are the tips that actually maximize your MacBook Pro battery: some by a little, some by a lot.
1. Lower Your Brightness
Despite all the advances in battery and display technology, the large glowing object on your laptop is still the greatest power draw. Perhaps this comes as no surprise: its main job is converting electricity into visible light, and it takes quite a bit of energy to accomplish that. This may change when MacBook Pros switch over to OLEDs in two-thousand-and-never, but for now, we’re stuck with our power-sucking LCDs.
Drop your brightness to the lowest comfortable level possible. Even if it seems dim at first, your eyes will adjust rather quickly. Mid to low brightness is also better for accurate color rendition since maximum brightness displays often increase the apparent saturation and lightness of a given hue.
2. Lean in to App Nap
If there’s ever been a placebo effect in extending battery life, it is quitting apps. Ever watch anyone diligently force quit a thousand background apps on their iPhone in an attempt to save battery? Makes no difference there because background apps on iOS can’t do much. They can query a server periodically for updates, but that’s about all.
Mac apps are a different story. Just because you can’t see the app doesn’t mean it isn’t merrily churning along, shredding your battery as it goes. Well-written apps don’t generally do this, but not all developers have been blessed by the Anti-Memory Leak Deity.
App Nap fixes this problem. If you can’t see an app, and it’s not making noise or accessing OpenGL, the app will go into a suspended mode called “App Nap.” In this mode the app takes no actions, ensuring it stops draining battery life without actually quitting. If and when you return to the application, it will reawaken instantly. If you want to force an app to nap, minimize or hide the application. Of course, you can also quit the app. But then you have the downside of relaunching the app and using more battery power sorting it out in memory.
You can view which apps are using App Nap from Activity Monitor. Open Activity Monitor from the Utilities folder, then click on the Energy tab. Click the title of the “App Nap” column to sort by napping status. If this column says “Yes,” the app is currently napping.
3. Disconnect USB Devices
Even when they’re not in use, devices connected over USB drain power. This includes USB drives, mice, keyboards, headsets, SD cards, and anything else you plug in. All these devices draw a certain amount of power, and some can draw quite a lot. Even in passive mode, a USB drive will pull an appreciable amount of power from your MacBook’s battery. Even devices that provide their own power source require communication, which can draw significant power. So unplug everything from your computer except the power cable. The same goes for Thunderbolt and USB-C devices on newer MacBook Pros.
4. Shut Off Wi-Fi
Your Macbook’s built-in radios draw power even when not connected. Wi-Fi is especially notorious for this. If you’re not actively connected to a Wi-Fi network, turn off the Wi-Fi radio. This prevents battery loss due to constant “hunting” for a preferred Wi-Fi network and from constantly refreshing the list of currently available SSIDs. When you’re on an airplane, for example, you can safely disable the Wi-Fi to improve battery endurance.
5. Use Safari
Safari is designed to be power sensitive. Apple takes advantage of their tight integration between hardware and software to ensure Safari uses as little power as possible. The difference can be dramatic, especially if you’re careful about keeping the numbers of tabs in check.
Firefox has this high CPU usage issue, even if you just open it and don’t run anything on it. Chrome also has the same memory issue when you have multiple tabs opened. If you are looking for the browser with the best battery performance and tightest integration with the OS, Safari is the one to go for, even if it is not the most feature-rich.
6. Reduce Memory Footprint
Some apps, like Chrome and Firefox, are all too happy to suck up as much free memory as possible. While most browsers want around one gigabyte of memory just to get up in the morning, additional tabs quickly increase the memory – and therefore battery – occupied by the app. Shut down stale tabs to keep your footprint small.
7. Keep an Eye on Runaway Apps
macOS offers two useful tools for tracking runaway apps. The first is the battery status menu bar dropdown, which provides an “Apps Using Significant Energy” contextual warning. If these apps aren’t essential to your current process, shut them down.
You can also monitor overly ambitious apps from Activity Monitor’s CPU tab. Keep an eye on the percentage usage for high-powered apps to make sure they don’t run at full tilt for too long.
Conclusion: Audit Your Energy Settings
All of this doesn’t mean much if your Energy settings are wasteful. Check out the “Energy Saver” preference pane in System Preferences, and ensure your settings on the battery are reasonable. Make sure the computer sleeps quickly when not in use and shuts down hard drives when possible.