Add "data transferred to carbon" calculation in the reports

[mrchrisadams]

We have a rough interactive model for calculating the Co2 impact for sending files around here:

https://observablehq.com/@mrchrisadams/carbon-footprint-of-sending-data-around

And below is where I implemented the model from, which also accounts for the carbon intensity of the grid:

https://github.com/thegreenwebfoundation/Carbonalyser

Add another check to convert requests to carbon with give us actual figures, by counting the bytes for each request made, the same way the carbonalyser does.

A first version, and approach:

• make a note of every domain data is requested from
• total up the data for that domain, counting the bytes sent for each network request made
• for grey domains, sum up the total data to CO2 using the simple model, assuming uniform carbon intensity across the internet (we know, it's it's not, but lets assume for now)
• for green domains (which already have a check for now), multiple using the same model, but assume the server part of the energy served is 0.
• present the data per domain in a table.

what this doesn't do

This doesn't model energy well enough to take into account CDNs, or count the hops, like you might with trace route. I'm not sure even that would represent it will enough, as we'd probably need to account for the fact that data over a cellular connection is energetically more expensive than data over the backbone style cables in use in most places.

Modelling this would be possible, but we'd almost definitely need substantial funding to do it accurately.