alt Hacker News> I think the Pi 3 range is a sweet spot for low cost, low power draw, decent-enough CPU. Newer models draw increasingly more power; going from 1.4W to 2.8W may not seem like much, but that's half your battery life.
Is that with the same load? The chart in the article shows a Pi 3 and Pi 4 using the same idle power, with the 4 drawing more under full load. But the 4 can do more at full load, raising the question of what would be the 4's power usage running a load equal to the 3's full load?
The author's chart is incorrect. He has the idle power at "1" for the Pi 2, "2" for the Pi 1/3/4, and "3" for the Pi 5. No other published power draw numbers are whole numbers like this, they are floating points, like 1.2, 1.9, etc. Google around and you'll find several different power testing comparisons with more detail.
Most reports show the Pi 4 drawing ~2.8 W in idle headless mode, and the Pi 3B+ drawing ~1.9-2.0 W in idle headless mode. With full load the Pi 4 draws more (6.4W, to the Pi 3B+'s 5.1W) with the same test procedure.
But you do have to check the testing method; enabling/disabling hardware features changes the figure, and each additional USB peripheral draws more power. Otoh, to get a "max power draw" reading you have to enable everything and stress all CPUs at once, and then it will dip under thermal load.