Which environmental and data choices are hidden by a model’s apparent performance?
A benchmark score shows what a model can do. It does not show what the model costs, or where its data come from.
Slides: CC BY 4.0. Lesson page and worksheet: maehr.github.io/stochastic-parrots-and-beyond
1. Scale is not a sufficient criterion
Bender et al. ask: “How big is too big?” (2021, 610).
Rising costs “doubly [punish] marginalized communities”: they benefit least and suffer the environmental consequences first (610).
A language model stitches together linguistic forms “without any reference to meaning: a stochastic parrot” (617).
2. Models have a material footprint
Energy: data centers used about 415 TWh in 2024, about 1.5% of global electricity. The IEA projects about 945 TWh by 2030, with AI as the main driver (IEA 2025).
Water: training GPT-3 could directly evaporate about 700,000 liters of fresh water, according to an estimate by Li et al. (2025).
Hardware: manufacturing servers and GPUs causes emissions before the first computation (Luccioni et al. 2023).
Estimates and projections. Use them as orders of magnitude.
3. Use costs energy again and again
Each request needs energy. Use is not a one-off cost.
Multi-purpose generative models are “orders of magnitude more expensive” than task-specific systems for several tasks (Luccioni, Jernite, and Strubell 2024).
The same computation causes different emissions on different grids.
4. Data choices are value choices
A larger web dataset is not a more diverse dataset (Bender et al. 2021, 613).
One corpus discarded every page with a word from a list of about 400 “bad words”. This also suppresses spaces “built by and for LGBTQ people” (614).
Undocumented data create “documentation debt” (615).
Case: BLOOM
Documented case
Data: Luccioni, Viguier, and Ligozat (2023). Original chart, CC BY 4.0.
What the BLOOM figures reveal
The grid: 57 g CO₂eq per kWh in France. The authors explain the low emissions largely with this grid.
Experiments: intermediate models emitted 35.8 t from dynamic power use, more than the 24.69 t of the final training on the same boundary.
Use: 230,768 requests in about 18 days used 914 kWh. Roughly 75% of the energy kept the model in memory, ready for requests.
Data: the 1.6 TB ROOTS corpus in 46 natural and 13 programming languages came with a data governance effort.
Sources: Luccioni, Viguier, and Ligozat (2023); Laurençon et al. (2022); Jernite et al. (2022).
Activity · 15 minutes
Trace one model or use case from its data sources to its use. Groups of three or four, on paper or on a laptop.
Choose a research-use card from your group. Use BLOOM only if no card fits. (3 min)
For each stage, note what is known, unknown, and avoidable, with a source. (8 min)
Mark the largest unknown and one avoidable cost. (2 min)
Prepare one sentence for the plenary. (2 min)
Worksheet: Lens 1, material-and-provenance map
Expected output
A material-and-provenance map for each group:
known, unknown, and avoidable costs for each stage,