Hacker News Reader

The fuses are typically 10A and there are products that go right up to that. You can probably safely use 8A in most cars. So about 100 watts.

15A on my mx5, cigarette lighters are short circuits that incandesce in open air without disintegrating.

Obviously not a short circuit. The element has a carefully chosen value of resistance.

I was being hyperbolic. It's obviously a substantial power draw, like the window defroster.

On an older car I remember the cigarette lighter fuse being 30A.

The three car manuals I just looked at were 10A, 10A and 15A.

I saw in German magazine that you can charge your car from the cigarette lighter, so i presume that it gives you a lot of power.

Or more likely a relatively small amount of power which would take many days to have any useful effect.

Quite feasible - typical car chargers have two rates, what we used to call 'trickle' charge up to about 4 amps, and 'fast' charge that will push 8 amps or more. The latter isn't so great for battery long-term health but is useful for 'got to start the engine now' situations whereas trickle is more for 'top the battery up overnight' situations.

Most accessory sockets are rated 10 or 15 amps.