Power is not energy: why the difference matters
Technology Connections2 HN recommenders · recommended in 2 months, 2025–2026
explainer · general · evergreen · 2025–2026 on HN
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.
HN points to it whenever a thread mixes up power and energy, such as battery specs and solar generation.
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5 comments from Hacker News
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
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 >.
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
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
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