Training and running large AI models consumes real, meaningful amounts of energy and water, and the environmental cost of AI is a genuine consideration, not a solved or negligible one. Precise, comparable figures are hard to pin down and vary enormously by model size, training approach, and hardware, but the underlying dynamic (more compute means more energy) is straightforward and worth understanding honestly.
Where the energy cost actually comes from
Training
Training a large model from scratch means running enormous amounts of computation across many specialized processors over an extended period, which consumes substantial electricity. The data center infrastructure also requires cooling, which often means substantial water use. This is typically a large, one-time cost per model version, not an ongoing per-use cost.
Inference, at scale
Each response a trained model generates uses far less compute, and less energy, than training did. Multiplied across the enormous number of queries a popular AI system handles, though, the aggregate energy cost of inference over a model's deployed lifetime can meaningfully exceed the one-time training cost, depending on how widely and for how long the model is used.
Why precise comparisons are genuinely difficult
Energy consumption figures for AI training and inference vary enormously based on model size, hardware efficiency, data center energy sources, and cooling methods, and providers don't disclose this information in comparable ways. Treat any specific number claiming to be "the" energy cost of an AI query with real skepticism, because the actual figure depends heavily on the specific model, hardware, and data center involved.
What's more reliably true, even without precise figures
- Larger models generally require more energy to train and run than smaller ones. That makes model size an energy tradeoff as well as a capability tradeoff.
- Data center energy sources matter significantly for the actual environmental footprint. Electricity from renewable sources has a very different impact from electricity generated by fossil fuels, and the mix varies by provider and region.
- Efficiency has been improving. Newer model architectures and specialized hardware generally deliver more capability per unit of energy than earlier generations, though rising overall usage can offset some of that gain in aggregate.
What this means for a business making AI infrastructure decisions
Using an appropriately sized model for a given task, rather than defaulting to the largest, most capable model whether or not the task requires it, is both a cost and an environmental consideration. It's the same reasoning covered in choosing a reasoning effort budget: match capability to actual need rather than defaulting to maximum.
How we approach this
We help clients match model size and capability to actual task requirements, rather than defaulting to the largest available model, for both cost and environmental reasons. We're also honest that precise environmental figures for AI usage remain hard to pin down with confidence.