RE: Introducing a new HTTP response header for Carbon Emissions calculation

Thank you for the support!

WRT the name of the header, I thought the trend was on full length header names, but I am definitely open to suggestions. That's actually the most important part of this specification: make sure everybody uses the same name!

I think it is important to specify "Scope-2" in the name of the field to make sure everybody understand what we're reporting. Also, in the future we may report carbon emissions in Scope-3, or other definitions from the GHG Protocol, or another standardization body.

Possible alternatives:

* Carbon-Emissions-Scope-2
* CO2-Emissions-Scope-2
* CO2-Scope-2
* Carbon-Scope-2
* Carbon-S2
* C02-S2

It doesn't seem to me that the proposed "Carbon-Emissions-Scope-2" is too long, but it's just an opinion. Are there any rules or standard on this?


Bertrand Martin<>

From: Tim Bray <>
Sent: Tuesday, April 11, 2023 6:11 PM
To: Bertrand Martin <>
Subject: Re: Introducing a new HTTP response header for Carbon Emissions calculation

I enthusiastically support this idea. I disagree with the list-of-decimals proposals - when I invoke a service I want to know how much carbon it cost, and maybe I want the provider to reduce it; so the list of decimals would be something that might happen behind the provider's firewall, to help them understand contributions to the load. Do the simplest thing first.  And if you did provide such a list, it would be more useful as a set of name/value pairs, and then you'd have to agree on the available names and extension mechanisms, and at least two years would have gone by. This could be shipped in months and would be a big step forward.

Since Scope-2 talks about CO2-equivalent emissions, and the name as proposed is REALLY LONG, maybe instead "Scope2-CO2"?

On Tue, Apr 11, 2023 at 6:26 AM Bertrand Martin <<>> wrote:
Hi, (newbie here)

I submitted a new I-D to define a simple HTTP response header field with the amount of CO2-eq in grams emitted by the processing of the request and the production of the response:

Carbon-Emissions-Scope-2: 0.0000456

The goal:
If HTTP servers are able to calculate or estimate this value, it will allow clients and applications to assess their Scope 3 carbon emissions. It is critical that we define a standard header for reporting this metric to help organizations assess the carbon emissions associated to the consumption of external services, SaaS, or even a Web site, a Google search, a ChatGPT response, etc.

Note: We're talking about Scope-2 emissions only (i.e. associated to the electricity consumed while performing the service), because you only need to take into account the Scope-2 emissions of your suppliers when you estimate your own Scope-3 emissions. See  and for more information on Scope 1, 2 and 3.

Any chance this would be looked at by the HTTPbis WG? I believe this could transform the industry in how it handles carbon emissions.

Thank you!

Bertrand Martin<>

Received on Thursday, 13 April 2023 23:26:38 UTC