Power is not energy: why the difference matters
Why Hacker News recommends it
HN points to it whenever a thread mixes up power and energy, such as battery specs and solar generation.
What it is
Technology Connections explains the difference between power (watts) and energy (watt-hours) and why confusing them leads to errors. It runs about 52 minutes and uses everyday examples.
Recommended by 2 HN commenters across 2 different months, 2025 to 2026.
What Hacker News said
Recommends VogonPoetry · 2025-04 · on “Watts Should Replace MAh as Essential Spec for Mobile Devices”
Yes, totally agree. Also a paragraph on the relationship between energy, heat, cooling and that computers effectively turn all energy into heat might have been useful. The April 1st date on the article is telling. Shout out to "Technology Connections" YouTube channel for recently publishing "Power is not energy" - < [this video] >.
Recommends DavidVoid · 2025-06 · on “Neuromorphic computing”
There is indeed; Watts aren't energy, and it's a common enough mistake that Technology Connections made a pretty good 52 minute video about it the other month [1]. [1]: [this video]
Cites DavidVoid · 2025-08 · on “Japan has opened its first osmotic power plant”
I don't see how kilowatts would be more sensible than kilowatt-hours here, especially since the power output might not be consistent. See also, "Power is not Energy": [this video]
Cites Kye · 2026-02 · on “Following 35% growth, solar has passed hydro on US grid”
He has a whole video[0] on the difference between energy and electricity, so he understands it. Maybe there's some disconnect between the video and your interpretation. [0] [this video]
Critical minimaxir · 2025-06 · on “The Gentle Singularity”
It's more that every time the topic has come up, it's reported in watts and I'm not sure if there's a nuance I'm missing. It's entirely possible those reports have been in watt-hours though and using watts for shorthand. I still find the Technology Connections video counterintuitive. [this video]