Tokens per Watt: What an AI Data Centre Actually Produces

Business Pill 13 · What an AI factory produces

An AI data centre is a factory: electricity goes in and tokens come out. When power is the limit, the number that matters is tokens per watt.

A short explainer video. The numbers in it are round numbers for illustration.

The Short Answer

Think of an AI data centre as a factory. Electricity goes in, and tokens come out. A token is a small piece of text, roughly a word.

So what limits the factory? Not the building, and not even the chips. It is the power. A site is connected to the grid for a fixed amount of electricity.

The Measure That Matters

If power is fixed, the question becomes simple: how many tokens can you produce from each unit of power? That measure is called tokens per watt.

It is a ratio of what the factory makes to what it uses. Because the power is the part that cannot grow, the ratio is where improvement has to come from.

A Worked Example

The video uses round numbers. A site has 100 MW. With one generation of chips it produces 1 billion tokens a day. A newer generation, on exactly the same power, produces 3 billion.

Same building, same electricity, three times the output. Since tokens are what the factory sells, that is three times the revenue.

Bar chart: an older chip generation produces 1 billion tokens a day and a newer generation 3 billion on the same 100 MW
Three times the output from the same power. Round numbers for illustration.

How It Changes the Way Chips Are Judged

When power is the limit, the cheapest chip is not the best one. The best one is the chip that turns each watt into the most tokens, even at a higher price.

It also explains why older chips are replaced while they still work. They are not broken. They are occupying power that a newer chip could turn into more output.

Three Questions to Ask

  1. How much power does the site have?
  2. How many tokens does each watt produce?
  3. How fast is that number improving?

See It in the News

Applied Digital’s 250 MW Milestone and the Megawatt Gap. A news piece about how megawatts are counted when power is the binding constraint.

How This Concept Connects

Layer 1 of 8 · Compute & Energy, on the Business Engineer Concept Map

GPUsTokensTokens per Watt
  • Tokens per Watt builds on GPUs. Tokens per watt judges chips by how many tokens each unit of power yields, so it needs the GPU lesson’s picture of AI chips.
  • Tokens per Watt builds on Tokens. Tokens per watt measures a data centre’s output in tokens, the unit the tokens lesson defines.
Business Engineer framework
AI Data Centers
Power is the fixed input of AI data centres; tokens per watt is their output ratio.
Business Engineer framework
The State of the Inference Economy
Inference efficiency and cost per token.
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