Originally Posted by
lwildernorva
Just tried an experiment on a Skoda Octavia I've rented in Ireland. Using a relatively high quality USB-C cable in one of the car's USB ports, I'm getting 45W so I probably can charge most but not all devices requiring USB PD. It's a new model with just 2K km on it so I don't know about models from earlier years, but I've never gotten the impression that Skodas are cars with cutting edge tech so I would suspect a number of 2025 and 2026 models now offer this level of charging power. If you're driving for stretches of several hours, you can probably recharge a device or two from empty using these ports…
Unless that 45W output from the port was capped to only be offered as 15V, i.e. at @3A (from what I remember of current chargers, a cap at 15V is unlikely, but I guess possible), it would also need to be
[email protected].
(IIRC, if a charger is 20V capable, it
must also support 5V, 9V and 15V, as well can optionally support 12V and /or PPS).
Any device which is rated for >45W input also must accept 20V (even if it does 140W/28V, 180W/36V or 240W/48V EPR charging).
So while it may not charge
fast, that 45W inflow (at 20V) should at least top up the device unless it is on and drawing significant power (most laptops will use ~<20W at idle, down to even <5W), and even then that 45W will supplement and help slow the power drain on the battery.
(Some devices will take 15V, as well as possibly even 5V, 9V and/or 12V too, but trying to research if any specific device will do so is a pain to figure out… I do know the Surface Pro and Macbook Air are two such devices, however, they accept all the way down to 5V.)
But yes, better to just carry a <100g charger.
Originally Posted by
gfunkdave
I think USB-C ports are becoming more common as places buy new furniture that has USB charging built in, but I doubt many of those ports can output the 65W that you'd need for most laptops. They probably top out at 18 or 30 watts, which is good for charging a phone or tablet and not much more.
Originally Posted by
gfunkdave
Also I'm not sure where this idea of different cable qualities comes from. Sure, there are some sketchy cheap cables out there but anything with the usb-c certification should be fine up to 65W. Special cert is needed for higher power (and those cables have a chip that identifies them as high power capable if you plug in a higher power charger).
Both my old Lenovo and Dell work ultrabooks used to complain about the 30W (
[email protected]) charger that I plugged them into when travelling, but they would charge, albeit slowly… most of what I did just did not consume much energy; the security crapware running in the background probably consumed more. I’d say it was under 25W 95% of the time, the remaining power from the charger (after conversion back for the battery) was enough to basically trickle-charge the battery.
Having said that, again, preferably you’d want the charger’s 30W to particularly include
[email protected], not just 15V@2A: I think the former is prevalent, but I guess the latter could exist.
I probably would not have tried that with a proper heavy-duty workstation or gaming laptop, however.
And yes, most non-sketchy brands’ USB-C cables of same power & data specs will perform the same. A 60W cable will carry 60W.
(Yes, shielding can maybe play a part, but I’ve not heard of issues if just considering mainline brands, they should have that aspect down).