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0 pointsorev4y ago0 comments

The weight of all those single purposes wireless chargers on planes is already a nonstarter. Airlines track weight of standard items down to the ounce, to the point that the in-flight magazines finally got removed because they were not justifying their collective weight. While many planes now have inverters where you can use an AC adapter, which can be used for phones, tablets, laptops, etc. wireless chargers can only be used for (some) phones, and they have bad efficiency (which effects fuel usage).

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cromka4y ago

What you described is a de-facto 'now` situation. In 3-5 years, basically everyone who travesl planes will have replaced theirs with wireless charing ones, if they haven't done so already.

> and they have bad efficiency (which effects fuel usage).

Compared to the amount of energy jet engine consumes each second, a loss on wirelessly charging ~100 phones is really just a joke in comparison: 2500mAh * 3.7 volt * 100 = 925Wh. With, conservatively, 60% efficiency of wireless Qi chargers, that's a 370Wh loss. Not even half a kilowatt-hour.

A 787 plane uses 7000 liters of jet fuel, for a total of 490,000 KWh during a 7 hour flight. (https://www.quora.com/How-many-kilowatt-hours-of-energy-does...)

So charging those phones wirelessly increases the amount of fuel consumed by 0.37/490.000 = 0.00007551020408%

If 1 liter of jet fuel currently costs $0.611, that's $0.61170000.000075551=$0.32 cents.

32 US cents. That's the cost of the increased fuel usage.

orevOP4y ago

I appreciate your math, but you’re not addressing what I said. I’m talking about weight of the devices, not the power loss/inefficiency of wireless charging. Wireless chargers require relatively a lot of wire in coils, and that adds weight. Additional weight costs fuel all the time, regardless of whether people are using it.

Given that some planes already have inverters to provide power for many types of devices, including phones, it does not make sense, from a weight perspective, to add another type of charging that can only be used by phones. It would be redundant. The power loss from wireless charging itself is just an aside.

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