Comparing Apple 70w vs. 96w adapters - is one better?
Added 2024-07-21 23:41:16 +0000 UTCHello, I put together a basic presentation, it needs a lot of work still, but this is just a first pass.
Definitely still working on things and will be getting more videos out soon.
The basic idea is that using many non-pfc adapters on a system versus using a high pfc adapter on a system changes the performance of the adapters even if on paper analyzing one device looks far better.
This applies to offices and places where multiple power supplies are strung together more so than other systems. Lighting systems mostly took care of this already with very good performance across that industry but power adapters, which keep increasing in wattage, don't seem interested. This can apply to your household as well, but the effect is smaller as the many devices are spread across more circuits. The calculations are not complex but tedious so I think the general rule is 'it's good enough'. The question is, is it worth getting the last few percentage points of efficiency out of systems?
Let me know if you think this should make it's way to a video or something similar, probably made generic, and well, finished, ha. Let me know if it is helpful in any way and what should be added or removed.
Comments
Can't wait for the next video! Any chance you'd be interested in doing Patreon giveaways of some of your recommended products?
Shwing
2024-07-22 05:43:05 +0000 UTCThat was fantastic, very interesting. Using the apple adapters worked to make the hypothetical scenario more understandable and justify many of the parameters. My understanding was very hand-wavy before, something like "lots of bad PF adapters -> lots of noise in the voltage -> probably not great for efficiency of all the adapters/devices, also possibly annoying noise for my electronics experiments". Seeing what some concrete calculations look like was great. I think a little bit more explanation is needed just before slide 15, to show specifically what numbers went into the overall losses for the 70W adapters vs 96W adapters, that contributed to the total power/year figures. I understand you probably want to try to simplify things even more for a broader audience, just show what kind of factors go into to, but it would be nice to see a more clear connection/linkage to the final numbers on slide 15 IMHO. (The skin effect analysis was interesting, but I was a bit unclear on the relative power of each harmonic, which would influence the relative contribution to the overall resistance ... and for the 3.26% increased average resistance, I assume this is just for the 70W adapter scenario, which has much stronger harmonics.)
Pierce Lopez
2024-07-22 05:01:29 +0000 UTC
