Lens 1: Stochastic Parrots

Scale and Environment

Laura Wagner and Moritz Mähr

Learning question

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

Horizontal bar chart of the 50.5 tonnes of CO2 equivalent for BLOOM's final training. Dynamic power use: 24.69 tonnes. Idle infrastructure: 14.6 tonnes. Manufacture of the hardware: 11.2 tonnes.

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.

  1. Choose a research-use card from your group. Use BLOOM only if no card fits. (3 min)
  2. For each stage, note what is known, unknown, and avoidable, with a source. (8 min)
  3. Mark the largest unknown and one avoidable cost. (2 min)
  4. 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,
  • a source for each entry,
  • the largest unknown and one avoidable cost.

Sources

Takeaway

Performance is what a model shows. Provenance and footprint are what it hides. A missing number is an unknown, not a zero.