Livre écrit avec l'IA

Name: Book written with AI
Creator: Projet Celsius
License: https://creativecommons.org/licenses/by/4.0/

Projet Celsius

Database entryUsesLevel 4 of 6 occupation or activityOccupation or activity, level 4 of 6Calculated with 7 entries, levels 1 and 3Database structure

Book written with AI

A 200-page book of about 80,000 words, in which each page is first drafted and then revised twice with AI. Projet Celsius estimate.

"Proofread a page" accounts for 32% of emissions in this scenario.
100% of the calculation rests on database assumptions; it does not measure actual use.
Out of scope: printing, server manufacturing and model training.

Compare

Calculated with

Breakdown of emissions by item

340 gCO2e in total: 750 Wh of electricity × 458 gCO2e/kWh (servers worldwide).

Inputs of the calculation 9

PUE of the data centre, Read 1,000 tokens, Write, with reasoning, Re-read from cache, Generate an image, Proofread a page, Conversation of 10 exchanges, Literature search, Web search (benchmark)

How the calculation is built

A 200-page book of about 80,000 words, in which each page is first drafted and then revised twice with AI, with outline sessions and a cover. The volumes are assumptions.

Comparison with other occupations and activities

See the full list

Book written with AIthis entry340 gCO2e

End-to-end study540 gCO2e

Automated monitoring, 1 year7.6 kgCO2e

Video of 3 minutes8.4 kgCO2e

Application with an agent12 kgCO2e

Logarithmic axis: each tick is 10 times the previous one.

Characteristics

Unit	1 project
Default location	world, 458 gCO2e/kWh (Ember 2025, life cycle); 11 other locations to choose from
Counted	the first draft, the revisions, the manuscript reviews, the cover and the cooling of the data centre
Not counted	printing, server manufacturing and model training
Status	estimated

All the characteristics identifier, version, rule for the value, sources, licence

Identifier	IA-0331, projetcelsius.com/en/ai/database/IA-0331/
Version	0.1 of 2 November 2026
Category	Occupations and activities, one person, one year
Choice of the selected value	database calculation from the entries this one is made of, at the quantities of the unit
Sources	calculation of the database
Licence	CC BY 4.0

Emissions by server location

Emissions associated with electricity (CO2e)

Poland440 gCO2e
World340 gCO2e
United States290 gCO2e
European Union160 gCO2e
France31 gCO2e

× 14 between Poland and France, for the same electricity

Ember 2025, over the life cycle. The same use consumes 750 Wh in each location.

Book written with AI · result per project · estimated · one server location per row.Counted: the first draft, the revisions, the manuscript reviews, the cover and the cooling of the data centre. Out of scope: printing, server manufacturing and model trainingFind this case: projetcelsius.com/en/ai/database/activities/book-written-with-ai/Calculation by Projet Celsius, AI Impact Database, version 0.4 of 13 November 2026 · IA-0331, entry in version 0.1 · engine 0.3.1 · CC BY 4.0.

Usage parameters

Advanced settings model class, reasoning, image size, calibration

Model classReasoningImage sizeCalibration

Result for the chosen case

Location of the servers

For a carbon footprint

The row for a carbon footprint

Item	purchases of services (GHG Protocol scope 3, category 1); regulatory BEGES, category 4
Quantity	1 project
Factor	340 gCO2e per project, IA-0331 version 0.1, using the local grid mix (location-based), servers worldwide
Total	340 gCO2e · not counted: printing, server manufacturing and model training

Breakdown of emissions by item

Emissions associated with electricity (CO2e)

Proofread a page110 gCO2e · 32 %
Literature search66 gCO2e · 19 %
Conversation of 10 exchanges65 gCO2e · 19 %
Query a PDF43 gCO2e · 13 %
Write a page41 gCO2e · 12 %
Visual in 4 attempts18 gCO2e · 5.1 %

Book written with AI · result per project · estimated · servers worldwide.Counted: the first draft, the revisions, the manuscript reviews, the cover and the cooling of the data centre. Out of scope: printing, server manufacturing and model trainingFind this case: projetcelsius.com/en/ai/database/activities/book-written-with-ai/Calculation by Projet Celsius, AI Impact Database, version 0.4 of 13 November 2026 · IA-0331, entry in version 0.1 · engine 0.3.1 · CC BY 4.0.

Breakdown by item

Quantity, unit value, contribution and nature of the data for each item

Item	Quantity	Unit value	Contribution	Share	Nature of the data
Proofread a page	× 400	0.6 Wh	240 Wh	32 %	assumption
Literature search	× 5	29 Wh	140 Wh	19 %	assumption
Conversation of 10 exchanges	× 40	3.5 Wh	140 Wh	19 %	assumption
Query a PDF	× 20	4.7 Wh	95 Wh	13 %	assumption
Write a page	× 200	0.45 Wh	90 Wh	12 %	assumption
Visual in 4 attempts	× 3	13 Wh	38 Wh	5 %	assumption

Entries that use it

No other entry in the database is calculated from this one.

Sources of the calculation

7 publications, for this entry and those used to calculate it, with the chosen parameters.

The result is calculated by Projet Celsius. The sources below support its uses, its factors and its conversion; they do not all measure this total.

Uses and assumptions

These publications shed light on AI tasks and uses. They do not measure the carbon footprint of the case calculated.

Epoch AI · February 2025
How much energy does ChatGPT use? ↗ (new tab)
Re-read from cache
Role and limits : Epoch AI
What the publication covers. the calculation from the hardware and the assumed size of the model
What it does not cover. actual measurements
Reading by the database. A public, transparent calculation
- Conversation of 10 exchanges → : Re-read from cache →
  The context re-read from cache at each turn: the previous exchanges, and the document already in the conversation if there is one
  Scope of the figure used. server, convention C4
  Limit. The quantity and the share entrusted to AI are database assumptions, not a measured footprint.
Projet Celsius · November 2026
Tokens per word, per line of code and per cell, measured with 7 public tokenisers
Write, with reasoning · Read 1,000 tokens · Re-read from cache
Role and limits : Projet Celsius
What the publication covers. 479,888 words from 196 blog articles and their English translation, code from the site and the Python library, a table of measurements; tokenisers of GPT-4o, GPT-4, Llama 3, Gemini (via Gemma 3), Mistral, DeepSeek and Qwen
What it does not cover. the Claude tokeniser, not public
Reading by the database. A measurement on technical texts, figures included; to be repeated if publishers change their tokeniser
Projet Celsius measurement, repeated on request with the public tokenisers
- Write a page → : Write, with reasoning →
  Length convention: one page
  Scope of the figure used. A report page, headings and paragraphs included: between the 1,500-character sheet (250 words) and a full A4 page in single spacing (about 550 words, at 6.1 characters per word measured on our articles)
  Limit. This publication supports the quantity of text or content processed, not its carbon footprint.
- Proofread a page → : Read 1,000 tokens →
  Length convention: one page
  Scope of the figure used. A report page, headings and paragraphs included: between the 1,500-character sheet (250 words) and a full A4 page in single spacing (about 550 words, at 6.1 characters per word measured on our articles)
  Limit. This publication supports the quantity of text or content processed, not its carbon footprint.
- Proofread a page → : Write, with reasoning →
  Length convention: one page
  Scope of the figure used. A report page, headings and paragraphs included: between the 1,500-character sheet (250 words) and a full A4 page in single spacing (about 550 words, at 6.1 characters per word measured on our articles)
  Limit. This publication supports the quantity of text or content processed, not its carbon footprint.
- Query a PDF → : Read 1,000 tokens →
  Length convention: one page
  Scope of the figure used. A report page, headings and paragraphs included: between the 1,500-character sheet (250 words) and a full A4 page in single spacing (about 550 words, at 6.1 characters per word measured on our articles)
  Limit. This publication supports the quantity of text or content processed, not its carbon footprint.
- Conversation of 10 exchanges → : Re-read from cache →
  Length convention: one page
  Scope of the figure used. A report page, headings and paragraphs included: between the 1,500-character sheet (250 words) and a full A4 page in single spacing (about 550 words, at 6.1 characters per word measured on our articles)
  Limit. This publication supports the quantity of text or content processed, not its carbon footprint.
- Summarise 30 pages → : Read 1,000 tokens →
  Length convention: one page
  Scope of the figure used. A report page, headings and paragraphs included: between the 1,500-character sheet (250 words) and a full A4 page in single spacing (about 550 words, at 6.1 characters per word measured on our articles)
  Limit. This publication supports the quantity of text or content processed, not its carbon footprint.
- Summarise 30 pages → : Write, with reasoning →
  Length convention: one page
  Scope of the figure used. A report page, headings and paragraphs included: between the 1,500-character sheet (250 words) and a full A4 page in single spacing (about 550 words, at 6.1 characters per word measured on our articles)
  Limit. This publication supports the quantity of text or content processed, not its carbon footprint.
Zhang and Nam · June 2026
HANSEL: Extracting Breadcrumbs from Web Agent Trajectories for Interactive Verification ↗ (new tab)
Read 1,000 tokens
Role and limits : Zhang and Nam
Author. Yujin Zhang and Daye Nam
What the publication covers. 45 web agent trajectories: 13.16 steps and 6.02 pages visited per task on average
What it does not cover. electricity
Reading by the database. A small sample, which gives the order of magnitude of an agent's steps
- Web search with an AI → : Read 1,000 tokens →
  The 5 pages found, read by the model, and the question: web agents visit 6 pages per task on average
  Scope of the figure used. server, excluding the data centre
  Limit. The quantity and the share entrusted to AI are database assumptions, not a measured footprint.

Energy and factors

The references of the selected values and of the entries used in this calculation.

Google · January 2009
Powering a Google search ↗ (new tab)
Web search (benchmark)
Role and limits : Google
What the publication covers. a search, data centre
Reading by the database. Never remeasured
- Web search (reference) →
  Reference of the selected value
  Scope of the figure used. A search, data centre included
  Limit. Never publicly remeasured; Google's AI answers are not published
Luccioni et al. · October 2024
Power Hungry Processing ↗ (new tab)
Generate an image
Role and limits : Luccioni et al.
Author. Luccioni, Jernite and Strubell
What the publication covers. GPU, processor, memory
What it does not cover. data centre
Reading by the database. Open models only
- Generate an image →
  Reference for the variant "Standard image, from 512 to 1,024 pixels per side"
  Scope of the figure used. Average of the open models tested, 1,000 images; median 1.35 Wh, maximum 11.49 Wh
  Limit. Open models only; closed generators publish nothing
Watershed · Aug. 2026
Estimating GHG Emissions from AI Use: Framework for Corporate-Level Measurement ↗ (new tab)
Read 1,000 tokens · Write 1,000 tokens · Data centre PUE
Role and limits : Watershed
Author. Bistline, Ulissi, Davis, Glidden, Joyce, Li, Mohsenin and Suh (Watershed)
What the publication covers. factors per 1,000 tokens read and written at the server before PUE (host and standby machines included), PUE separate (1.10 for a large operator, 1.56 for an unknown operator)
What it does not cover. clean measurements, the model and the hardware
Reading by the database. Default factors proposed for review (public data as of June 2026); for a large operator, taken from Google's measurement published in 2025 (Elsworth et al.), which already contains the data centre overhead; constant per token, they underestimate long contexts and agents according to the authors
- Read 1,000 tokens →
  Reference for the variant "Medium model, Watershed default factor"
  Scope of the figure used. Default factor for 1,000 tokens read, medium model, large operator, at the server before PUE (Watershed table 2, public data as of June 2026)
  Limit. A default value that Watershed derives from Google's measurement (0.24 Wh for the median text query of the Gemini app), with about 500 tokens per query and a written token costing 3 times a read token; Watershed does not give the split between read and written tokens. The 0.24 Wh already include the overhead of Google's data centre (0.02 Wh, 8%): with 375 tokens read and 125 written, the simplest reading, the factor contains it, and the PUE of 1.10 applied afterwards counts it a second time (about 9%). Values proposed for review, final at the next version of the framework
- Write 1,000 tokens →
  Reference for the variant "Medium model, Watershed default factor"
  Scope of the figure used. Default factor for 1,000 tokens written, medium model, large operator, at the server before PUE (Watershed table 2, public data as of June 2026)
  Limit. 3 times the reading factor, based on the ratio between writing and reading selected by Watershed (Patel et al., Splitwise, 2024). Same derivation and same caveat as for reading: Google's 0.24 Wh already include about 8% of data centre. Values proposed for review, final at the next version of the framework
- Write a page → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.
- Data centre PUE →
  Reference of the selected value
  Scope of the figure used. Default factor for a large operator, from the server to the data centre; 1.56 for an unknown operator
  Limit. A default value, not a measurement
- Proofread a page → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.
- Query a PDF → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.
- Conversation of 10 exchanges → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.
- Web search with an AI → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.
- Summarise 30 pages → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.
- Article of 1,000 words → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.
- Visual in 4 attempts → : Data centre PUE →
  The data centre, convention C3
  Scope of the figure used. building cooling and losses
  Limit. This figure covers part of the calculation; it does not measure the whole entry.

Conversion into carbon

The source of the electricity factor of the selected location.

Worldwide: 458 gCO2e/kWh, life cycle.

Ember · 2026
Global Electricity Review 2026, and Our World in Data based on Ember ↗ (new tab)
Grid electricity
Role and limits : Ember
Author. Ember, Our World in Data
What the publication covers. electricity generation over the life cycle, by country
What it does not cover. guarantees of origin
Reading by the database. The same source for all countries
- Grid electricity →
  Conversion of electricity into carbon: worldwide
  Scope of the figure used. the production of electricity over the life cycle, including power plant construction and fuels
  Limit. An average for the chosen country, not the electricity contract or the data centre of a specific service.

Nature of the data

Published readings, conventions, assumptions

What this figure rests on

Projet Celsius assumptions 100 %

A share counts as an assumption as soon as a quantity set by Projet Celsius (a frequency, a share done with AI, a headcount) enters its calculation, even if the rest rests on published measurements.

Calculation assumptions

Quantities, nature and source of each assumption

Write a page : × 200
The first draft of each page: a book of 80,000 words makes about 200 pages of 400 words
assumption · Write a page
Proofread a page : × 400
Two rewrites per page
assumption · Proofread a page
Query a PDF : counted 20 times
About 20 readings of the manuscript in blocks of 30 pages, for consistency
assumption · Query a PDF
Conversation of 10 exchanges : counted 40 times
About 40 sessions on the outline, the characters or the chapters
assumption · Conversation of 10 exchanges
Literature search : counted 5 times
About 5 literature searches
assumption · Literature search
Visual in 4 attempts : counted 3 times
About 3 cover options of 4 attempts each
assumption · Visual in 4 attempts

Methodology conventions

With their alternatives

The full methodology

The standard query	A query counts 100 tokens read and 400 written · alternatives: 410 and 90 (Watershed calibration); 1,000 and 400
The data centre	Server electricity is multiplied by 1.10 for the data centre · alternatives: × 1.72 from chips to the full service at Google, never to be combined
The cache	A token re-read from the cache costs 10% of a token read · alternatives: bounds 1% and 25%
The default location	Without other information, the servers are in the world, at the world average electricity · alternatives: the United States, where most of the large assistants run
Electricity, location-based, on a life cycle basis	The kilowatt-hour is that of the servers' country, on a life cycle basis, from a single source for all countries · alternatives: market-based, with purchase contracts, shown alongside when published
Two significant figures	A calculated value is rounded to two significant figures, a published value is reproduced with the precision of its source; the calculation keeps full precision
The formula	the sum of what makes up the entry, then CO2e: electricity (Wh) multiplied by the carbon intensity of the server location (gCO2e/kWh), divided by 1,000
Calculate a case without an entry	The formula, the default values and a step-by-step example

History

Entry in version 0.1 of 2 November 2026, in the database in version 0.4

The changelog

2 November 2026Version 0.1 of the entry, as of the date of its current value.
31 October 2026Creation of the database, in its first version (0.1).

Citation

Projet Celsius, AI Impact Database, version 0.4 of 13 November 2026, "Book written with AI", IA-0331 (entry in version 0.1 of 2 November 2026), projetcelsius.com/en/ai/database/IA-0331/ · CC BY 4.0.

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