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Comment by funnybeam | Hacker News Reader

Just because the waste is small doesn’t mean it is insignificant when you consider how many phones there are.

A quick search indicates there are 3.5 billion smart phones in the world, assuming these are all wirelessly charged and wasting 1kWh per year that gets you 3.5TWh which is more than the annual consumption of many countries

I had a similar discussion with a friend recently about all the cars driving around with lights on in the middle of the day - even if they might be using LEDs, when you multiply by the number of cars on the roads that is still a lot of petrol being wasted for no reason at all

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Those lights are on for a reason. They're called Daytime Running Lights, and are mandated by law in most countries because they reduce accident rates by as much as 20% for a negligible cost.

If you think running some LEDs are expensive, you don't want to know what a serious accident costs society. The type that totals two cars and puts multiple people in hospital.

I have a car that pre-dates DRLs, and I always drive it with the lights on. The "horrendously" inefficient incandescent bulbs might cost me an extra dollar or two in fuel, but could save my life. I'd rather have my life.

Thanks for educating me - I was unaware of that and have changed my opinion.

For anyone else thinking like I was, this is the evidence from the UK government site [1]:

Research has shown that DRLs are likely to reduce multiple vehicle daytime accidents and fatalities by up to 6% once all vehicles are equipped. DRL are likely to result in a small increase in fuel consumption and CO² emissions of around 0.5% but this is expected to be lower when LEDs are used in place of filament light sources.

[1] https://www.gov.uk/government/publications/daytime-running-l...

Doesn't apply to wireless phone charging though, so I'm standing by that comment until someone disabuses me of that too..

> which is more than the annual consumption of many countries

Yes, countries like Liechtenstein, Papua New Guinea and Swaziland. Even a generous upper bound estimate like 3.5TWh is vanishingly small in the face of our ~21PWh annual global energy consumption. [0]

The point is: by focusing on wireless charging, we'd be investing effort in ineffective endeavors while there's far more low hanging fruit we could pick. And people's willingness to put in effort for the environment is a finite resource as well. So we should be smart about spending it.

For example: instead of worrying about daytime lights, how about cycling instead of driving, even just once in a while, whenever the weather is nice and you're feeling like it? That's sure to have a greater impact on the environment.

[0] https://en.wikipedia.org/wiki/List_of_countries_by_electrici...

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