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by allovernow 2380 days ago
Looks like buzzword marketing bullshit to me. Apparently they're just sending pulsed DC power over Ethernet cables? Nothing else in that article is as new or exciting as they dressed it up to be. GFCI outlets are standard in modern houses, they claim to be safely transmitting "high voltage" but 120V is not, and the "digital" buzzword stinks of marketing.

>It transfers high levels of power over non-power cable

You can't beat physics. Wires heat up from current, regardless of whether it's AC, DC, or "digital" pulsed DC. I doubt Ethernet cable is rated for any significant amount of power, but searching for "cat6 max power" doesn't return any relevant results because search is broken in 2019.

It's also likely to be rather inneffecient, as they are converting from AC to DC and then potentially back to AC? There may be an advantage to pulsing DC but I'm not sure, typically AC is more efficient for power transmission because of lower losses for the same power over distance and higher transformer efficiency (no need for an inverter).
3 comments
lopmotr 2380 days ago
It's apparently a bit smarter than GFCI. [1] says it measures the loss in the wire to determine if a person or whatever is touching it. So that would protect people against shocks from touching both wires, which GFCI can't do.

[1] http://magazine.connectedremag.com/publication/?i=488126#{%2...

I think this is a pretty nice idea except for the patents and only having one or two suppliers and lack of technical details.

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secabeen 2380 days ago
You can get 100W over Cat5 with 802.3bt, but I can't tell if there are any special requirements for that cabling: https://en.wikipedia.org/wiki/Power_over_Ethernet#Standard_i...
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p1mrx 2380 days ago
It sounds like "digital electricity" is a more advanced sort of GFCI: instead of verifying that the two pins are carrying equal current, it verifies that the expected amount of power makes it all the way to the receiving end.

Normally, running high voltage through a wire is dangerous because a fault can dump power into the middle of the wire (starting a fire) or into a person (stopping their heart), but perhaps with end-to-end active monitoring, it's possible to operate safely at much higher voltages?

If this technology works, I think it would also be useful for powering a tethered drone from the ground.

[Edit: according to lopmotr's link, they are using this for drones and balloons already.]

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