5 ms·
One problem is the DC voltage requirement is different for every device. Look at the wall-warts in your house. I have in my lab: 24V, 19V, 17V, 12V, 5V, 3.3V. Y
by SavantIdiot 5y ago
One problem is the DC voltage requirement is different for every device. Look at the wall-warts in your house. I have in my lab: 24V, 19V, 17V, 12V, 5V, 3.3V. Yeesh.
If you delivered 48VDC you'd still need a DC SMPS at each point, but an SMPS is way more efficient than a transformer.
- cadr 5y agoHow are you comparing the efficiency of a SMPS and a transformer? They are different things. Would love to hear more.
- Dylan16807 5y agoYou look at the percentage, such as 95%? I'm not sure what you're asking. Add up the losses in each conversion, plus the losses from the house wiring.
- MisterTea 5y agoMost AC power distribution transformers are 95% or better. As of 2016 the US EPA mandated even greater efficiency of 97% or greater: https://www.ecfr.gov/current/title-10/chapter-II/subchapter-D/part-431#subject-group-ECFRf791a7b3e315557 https://www.ecfr.gov/current/title-10/chapter-II/subchapter-...
- saalweachter 5y agoEvery time I look into this the conclusion I end up with is "not enough things are produced using 24V/48V DC to be worthwhile". It seems like you could replace a certain fraction of room wiring with PoE from an energy budget point of view -- lights, lamps, chargers and other doodads don't need to draw more than a few watts each, so you could get by with just an outlet or two per room for large power draws everywhere but the kitchen, and PoE for all the rest. But the world just isn't built for it.