Power
Every animated screensaver pays macOS a fixed price before it draws anything at all. We measured that price, then measured Nap against it, and against the screensavers Apple ships. Here is all of it.
The short version
On a 14-inch MacBook Pro at half brightness, running on battery:
| While it runs | The whole Mac draws | On top of a black screen |
|---|---|---|
| Display off | 1.2 W | — |
| Display on, showing black | 3.3 W | — |
| A screensaver showing a still picture | 3.5 W | +0.2 W |
| Flurry, from macOS | 6.1 W | +2.8 W |
| Nap, Paper Plane, on battery | 6.7 W | +3.4 W |
| Nap, Paper Plane, at full frame rate | 7.5 W | +4.3 W |
| Nap, Flip clock, on battery | 7.6 W | +4.4 W |
| Hello, from macOS | 7.9 W | +4.7 W |
| Nap, Flip clock, at full frame rate | 8.7 W | +5.5 W |
Nap sits among the screensavers macOS already ships: the Paper Plane costs less than Hello, Apple’s own animated default, and a little more than Flurry.
Where the power actually goes
A screensaver that animates costs about 3 W on this Mac before it draws anything of its own. We know, because we built a screensaver that moves one small white square on a black background and measured it: 3.0 W over a black screen. That is macOS’s screensaver machinery, not the screensaver.
On battery, Nap’s Paper Plane costs about half a watt more than that square. At the full frame rate it costs about a watt more.
So the difference between a plain screensaver and a beautiful one is small. The difference between a screensaver and none at all is not.
What we did to keep it down
Nap redraws only what moves. It used to redraw the whole display sixty times a second, background included. Now each screensaver reports the part of the screen it changed, and only that is redrawn. A test renders every screensaver in every style and compares each frame against a full redraw, pixel by pixel, so this can never quietly leave a smear behind.
On battery, Nap draws 30 frames a second instead of every frame your display can show. That saves about 1 W, and you can change it: in Nap’s settings, Frame rate offers Automatic, Smooth and Battery saver.
A still screensaver costs almost nothing. Once a trial ends, Nap shows a still map rather than an animation, and that costs 0.2 W over a black screen.
The bigger lever is your display
Nothing a screensaver does matters as much as whether your display is on. The display off costs 1.2 W; on and showing black it costs 3.2 W, before a screensaver draws a single pixel.
So if battery life matters more to you than seeing Nap, set your display to turn off a few minutes after your screensaver starts, in System Settings → Lock Screen. And if you have never seen your screensaver at all, that is probably why: on many Macs the display is set to turn off before the screensaver ever starts.
How we measured
- A 14-inch MacBook Pro (M4 Pro, 2024) running macOS 27, at 47% brightness with auto-brightness off, on battery, in September 2026.
- Power is the whole Mac, read from the battery gauge’s own accumulator, which adds up the system’s draw every second. Each figure is two published minutes, after letting things settle, with nobody touching the Mac.
- Each screensaver was measured against a black screen recorded minutes earlier in the same session. Where a difference was small, the two states were run alternately several times, because a session can drift by as much as the difference being looked for.
- Apple’s screensavers were measured exactly the same way. Aerial videos were not measured: none were downloaded on this Mac.
These are numbers from one Mac at one brightness. Yours will differ, but the order should not.