[ZeroGravitas]

Some people/corporations use those numbers to tax themselves. Microsoft does this I think as part of their commitment to carbon neutrality.

Better if it's done across society but not totally useless to be aware of that info even in the absence of a carbon tax.

Also, if they tax the fuel (which they certainly should) someone still needs to work out how to apportion that to the individual customers. Does the first person signing up pay the full wack, do you average it across all tickets, what if the plane flies half full, and so on. This is the kind of thing airlines do every day for the cost of fuel anyway.

[gruez]

>Also, if they tax the fuel (which they certainly should) someone still needs to work out how to apportion that to the individual customers.

Why is this even a problem? Fuel costs money today, yet airlines are somehow able to "apportion that to the individual customers".

[WalterBright]

Right. Every cost a company has is apportioned to the customers. This has to be done, otherwise a company cannot determine the price floor needed to stay in business.

[WalterBright]

Consider that so many thousands of companies are involved in the manufacture of the lowly pencil that there is no possible way to even determine the carbon footprint of it. Howinell can that work with a gigantic company like Microsoft? How can Microsoft's auditors come up with a remotely credible number? (They can't.)

But what makes it all work is the pricing mechanism of the free market, not some auditing system.

See Milton Friedman "Free to Choose"

[throwaway894345]

I think this is probably more of a marketing thing. Even though data centers consume a fair amount of electricity, software companies generate a lot more revenue per unit energy than most industries, so it's a lot cheaper for them to appear green than for, say, an air freight company who might be doing a lot more to reduce emission rates than Microsoft and yet doesn't sound as impressive as Microsoft's "we're [almost] carbon neutral".