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I'm having a very hard time rationalizing these numbers. Something has to have some very poor assumptions:

Let's assume each page load is ~1mbit, and it's being served from 1000km away. 1mbit may be low, but most of it will presumably be content delivered by a CDN which is far closer than 1000km.

The reference design (which I work on) for 400G DWDM systems are ~100W for 2 transceivers + EDFA + switches, for a standard 80km link. Assuming we hop every 80km (which should be conservative here), we get 3mJ for the energy through the network. The previous generation is probably 10x worse, so ~30mJ.

Let's add the endpoint too; Wifi router + cable modem (12W or rather 3W marginal power since it's running anyway/ 200mbit) = 15mJ

And finally for the server. I'd hope the server could do 1k requests per second, and that should amortize against backends, etc (2k RPS, but frontend + DB backend server, maybe), maybe 150W for the server, so 150mJ.

This gives us 200mJ for a page load. Using California's current (1:28am) emissions for power generation of 0.274 mT/MWh (it's 1/3rd of this during the day), this yields 15ug/request.

Where do the remaining 5 orders of magnitude come from? What am I missing? If TCO/production energy of the server was included, that couldn't more than double it (capex in a datacenter < opex, and if 100% of the server cost was for energy, we could double, but this is wildly conservative)

Here is the methodology https://www.bbc.com/future/article/20200131-why-and-how-does...

I think most of it comes from your client device. Your laptop may be using 50W of power or about 20g of CO2 per hour so reading the article for 6 minutes is ~2g of CO2.

That makes quite a lot of sense, but it also makes me frown a bit at the phrasing, which I feel is quite misleading.

"The digital emissions from this story are an estimated 1.2g to 3.6g CO2 per page view."

Re-reading it, technically they are right, if "view" is taken in a non-technical fashion. But everyone reading that text would assume if they click refresh, the emissions are doubled.

Also, I do wonder if they take into account bounced users - I would not be surprised if most people only spent 5 or so seconds on the page before moving on.

Also why not add sustinance cost for the human looking at the device then? Food, water, heating/cooling, clothes, glasses, etc...

Proportionally for 2 minutes of course.

Those costs would be the same if the article was read from a newspaper or magazine, so they can be factored out.

My desktop is on whether I'm reading the article or not so those costs can be factored out too.

Surely "view" should also include the human doing the viewing? :P

According to https://news.ycombinator.com/item?id=24068986, that's 1g every 90s, so 4g CO2 for 6 minutes reading time.

In case someone wants to do the math again :

50W for 1 hour : 50Wh or 0.050kWh

California : 187gCO₂eq/kWh according to https://www.electricitymap.org/zone/US-CAL-CISO

-> 9.35gCO₂eq/h -> 0.16g/min -> 0.935g for 6 minutes

I'd probably use closer to 10W as the device power level (a standard laptop, what I'm using right now), so the number for me would get close to 0.2g, but your point stands; the article is answering a different question than I was assuming, but regardless it seems that the majority of the energy is clearly the local device.

Isn't a modern laptop mostly idle after loading the page (< 5 seconds) ?

There would be a peak for the first seconds, then less than 10W for the rest of the reading time ?

Definitely the peak would be higher. My laptop has a ~60Wh battery and gets ~6hours of battery life, so I was just assuming 10W average for web browsing.

Thanks for the figures. I've bought an ARM PC in part for lowering its footprint.

Rest assured that you can make the numbers even worse by using a VPN thus requiring even more intermediate servers and cryptographic computations.

But before admonishing users please consider defending Net Neutrality and copyright reforms so that theses workaround become useless (for general usage). And while you are at it don't refrain from taxing ad-networks that use bandwidth and cpu cycle with over-engineered adware!

But nah, better stick to boomers worldviews, Governments and Big Corp can't do nothing for the planet because people are so dumb ¯\_(ツ)_/¯

How is this comment admonishing users? It looks like an attempt to put mathematical justification to a claim.

The comment is not admonishing anyone, it's about the underlying narrative the comment is addressing.

Sorry my ironic and rhetorical intentions might not have been clear enough, English is not my mother tongue so I might been confusing here.

Basically my point is that heavy calculation about "X is emitting Y shame on you people" is too often used as decoy so you never actually audit Z.

It's the bbc - accuracy is the very least of their concerns. They're much more focused on harassing pensioners for their state sponsored extortion racket money.

I'm not sure that's relevant to this discussion.

The government continues to reduce the amount of money they send to the BBC, which continues to produce world-class television and is struggling to find the money to do so.

They've decided that they will no longer offer the complimentary license to the elderly.

None of that should have any bearing on the accuracy of their environmental reporting.

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