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AI 电力需求会一直涨吗:从训练能耗、芯片效率到电网供给的逐条拆解

Yes, But

AI 导读

文章以美国数据中心 2023 年用电 176 TWh、2024 年 192 TWh 为起点,结合 Berkeley Lab 对 2025 年增长 22%、2026 年增长 29% 的预测,估算 2026 年 AI 用电约 75 TWh。

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AI is already a grid-scale load

US data centers used 176 TWh in 2023 (4.4% of US power) and 192 TWh in 2024. Berkeley Lab's reference case then has them growing 22% in 2025 and 29% in 2026, to roughly 300 TWh. EPRI estimates that 15–25% of that is AI. The IEA says AI-focused data centers grew 50% in 2025 alone. Put together, that is about 75 TWh a year for AI in 2026.

Training dominates the headlines (despite inference using more), since the single up-front cost raises eyebrows. GPT-3 took 1,287 MWh, and Grok 4 an estimated 310 GWh, 240× more.

More numbers

Energy to train one model

GPT-3 · 20201.3 GWh

Llama 3.1 405B · 2024~40 GWh

GPT-4 · 2023~50 GWh

Grok 4 · 2025~310 GWh

Log scale. GPT-3: Patterson et al. Llama: 30.8M H100-hours from Meta's model card × Epoch's overhead factors. GPT-4: estimate from leaked specs. Grok 4: Epoch AI. 310 GWh ≈ 29,000 US homes for a year.
Since you opened this page

0ChatGPT prompts served

0 Whelectricity at 0.34 Wh each

At mid-2025 volume (2.5B prompts/day ≈ 29,000/second). Volume has grown since; weekly users went from 800M to 900M+.

Yes, but GPUs are getting more efficient

Nvidia pitched Blackwell as up to 25× less energy per inference than Hopper. Vera Rubin, in full production since CES 2026, claims up to 10× more tokens per megawatt than GB200, and CoreWeave measured 10× on DeepSeek-R1. On Nvidia's own chart, energy per token on a 1.8T-parameter MoE fell from 17,000 J on Pascal to 0.4 J on Blackwell, about 45,000× in eight years.

The overall hardware trend is 1.28–1.40× more efficient per year (Epoch, Epoch), and the IEA says it is gradually slowing.

More numbers

  • Rubin's racks are fully liquid-cooled, with a PUE of 1.1 vs ~1.25.
  • Much of that headline gain is lower precision (FP16 → FP4), bigger NVLink domains and software, not the silicon itself. At fixed precision, Rubin's FLOPs per watt are roughly level with Blackwell's, and dense-model gains are closer to 2–3×.
  • Every chip trend before it slowed too. Computations per kWh doubled every 1.6 years until 2000, then every 2.6. Single-thread speed went from +52% a year to about +3%.
  • Physics also sets a ceiling: CMOS chips top out around 207× an H100's efficiency, and dropping from FP16 to FP4 has already used most of the number-format gains.
  • So we let the trend fade as it nears that wall, ~130× from Blackwell (range 26–650×). Ten years then yields 6–14× instead of 12–29×. Hold usage at today's level, and AI's electricity still falls every year, just less steeply.
Every chip trend slows down

Single-thread CPU speed, growth per year

1986–200352%

2003–201123%

2011–201512%

2015–2018~3%

GPU efficiency gain over 10 years

1.40×/yr, forever28.9×

1.40×/yr, fading11.3×

1.28×/yr, forever11.8×

1.28×/yr, fading6.9×

CPU: Hennessy & Patterson, 2019. "Fading" means the yearly gain shrinks so total gains level off at ~130× today's efficiency, the CMOS ceiling from Ho, Erdil & Besiroglu.
Energy per token, GPT-MoE-1.8T inference

Pascal · 201617,000 J

Volta · 20171,200 J

Ampere · 2020150 J

Hopper · 202210 J

Blackwell · 20240.4 J

Log scale. Nvidia slide deck.

Yes, but AI adoption is only at 2%

a16z's State of Markets II shows only ~2% of US households paying for an AI subscription as of April 2026 (PNC transaction data). Adoption is going to skyrocket in the next decade. AI is being adopted about twice as fast as the internet was in the '90s, and the internet went from 14% of US adults in 1995 to 68% in 2005. At twice the speed, AI's next ten years look like the internet's twenty, which reached 86% by 2015. If paid AI follows the same kind of S-curve, from ~2% of households to 68–86%, usage rises 34–43×, more than cancelling the hardware gains.

US adults using it, ~2 years after launch

Generative AI39.4%

Internet~20%

PC (3 years)~20%

Bick, Blandin & Deming.

Yes, but models are getting more efficient

The densing law (Xiao et al., Nature Machine Intelligence, 2025) finds that the capability per parameter of open LLMs doubles about every 3.5 months: the same score from half the model, every season. The preprint clocks a 266.7× price drop for equal performance, from GPT-3.5 (Dec 2022) to Gemini 1.5 Flash (Aug 2024). These improvements had a direct impact on energy usage. Google cut energy per Gemini prompt 33× in a single year.

Obviously these densing gains won't last forever. A decade of it gives an obviously absurd result: at the low end, all of America's AI running on less power than one house. The reality is requirements for a given capability slow sharply as that capability ages, but there are still tremendous gains to be made.

More numbers

Andrej Karpathy's GPT-2 reruns are a great way to view the progression of this. OpenAI's 2019 training run cost roughly $43,000. llm.c reproduced the 1.5B model in 24 hours for $672 in 2024. By March 2026, nanochat beat it in 1.65 hours, for about $48: roughly 900× cheaper in seven years, or 2.6× a year. On fixed hardware, the community speedrun to GPT-2-small loss fell from 45 minutes to 1.13. For the estimate here, we took the 2.6× a year (Karpathy) to 10.8× a year (densing law) and let it fade, with the yearly gain halving every 3–10 years.

Cost to train GPT-2-grade model

OpenAI · 2019~$43,000

llm.c · 2024$672

nanochat · Jan 2026$73

nanochat · Mar 2026~$48

Log scale. 2019 figure is Karpathy's estimate (32 TPU v3 × 168 h). nanochat README.

Yes, but TAM is larger than the population

Agents, not people, are now the #1 user of tokens. On OpenRouter, agent API keys out-used humans for the first time on February 6, 2026, and by late September they were using ~7× the tokens humans did. OpenClaw wakes itself on a 30-minute heartbeat by default, and Jensen Huang predicts a future with 100 billion agents. Agents are going proactive and are growing in use massively. Some of that 7× is cheaper than it looks: ~90% of agent tokens are cached re-reads of the same prompt. Weighted by compute, agents are about 1.5–2× human usage today.

We assume agent compute per adopter grows 2–20× by 2036, or about 1.07–1.35× a year.

More numbers

One day, 24 hours

You · ~3 prompts

Always-on agent · 48 wakeups

12am6am12pm6pm12am

Human: ChatGPT's 2.5B prompts/day ÷ ~800M weekly users. Agent: OpenClaw's default heartbeat, each resending its full context.
OpenRouter tokens per day (7-day average)

Humans · Feb 20260.5T

Agents · Feb 20260.51T

Humans · Aug 20261.4T

Agents · Aug 20267.3T

Log scale. a16z / OpenRouter (Peter Walker), via The Decoder. API keys classified as agentic or human by tool-call frequency and request timing.

Yes, but hardware is getting more optimized

There's a ladder of ways to serve a model, each more efficient and less flexible than the last: CPUs, then GPUs, then TPUs, then fixed-function ASICs. Most AI still runs on GPUs: Nvidia shipped 67% of new AI compute in Q4 2025. The top rung is Taalas's HC1, which hard-wires Llama 3.1 8B into the transistors themselves and gets roughly 3× a fully loaded GPU's tokens per joule.

We move ASICs from ~25% of AI power today to 40–70% by 2036, at 1.5–20× a GPU's tokens per watt: up to ~13× more AI from the same power.

More numbers

Llama 3.1 8B, tokens per joule

H200 · one user0.3

H200 · fully batched~25

Taalas HC1~68

Vendor figures, not independently benchmarked. H200 at 700 W, ~230 tok/s for one user vs ~17,700 tok/s fully batched (TensorRT-LLM, FP8, 1k/1k); Taalas HC1 at ~250 W and ~17,000 tok/s, assuming one stream is its full output.

Yes, but Jevons paradox

In 1865 William Jevons noticed that efficiency doesn't save fuel: when Scottish ironworks cut coal per ton of iron to under a third, Scotland's coal use rose tenfold. AI is following the same pattern. Google cut energy per prompt 33×, yet its monthly tokens went from 9.7 trillion to 3.2 quadrillion in two years.

Adoption and agents are already counted above, so the question here is how much more gets re-spent on top. AI's own record in 2025–26 implies 75–85%: most of every efficiency gain the earlier sections banked comes back as load.

More numbers

  • Jevons' line: "it is wholly a confusion of ideas to suppose that the economical use of fuel…" means using less of it.
  • Between 1800 and 2000, the price of light in the UK fell to under 1/3,000th, while light used per person rose 6,500× and total use 25,000×. Spending on light has held near 0.72% of GDP for 300 years, which amounts to roughly 100% rebound.
  • The one real counterexample: from 2010 to 2018, data-center compute grew 6.5× while energy rose just 6%. That ended once GPUs arrived.
  • "Jevons paradox strikes again!" posted Satya Nadella the week DeepSeek R1 landed. Frontier models now cost 3–18× more a year to run as savings get spent on bigger ones.
  • Where 75–85% comes from: in 2025–26 tokens grew 7× and energy per task fell ≥10×, yet AI data-center load still rose 50%.
  • The evidence is thin, and one study found demand inelastic across models.
Efficiency gain vs. how much more got used

Coal per ton of iron÷3

Scotland's coal use×10

Price of light, UK 1800–2000÷3,000

Light used, UK×25,000

Energy per Gemini prompt (1 yr)÷33

Google tokens/month (2 yrs)×330

Log scale. Green = efficiency gain, orange = growth in use. Jevons 1865, Fouquet & Pearson 2006, Google 2025, Google I/O 2026.

Yes, but the grid can't be built that fast

Right now AI is limited by supply, not demand. Satya Nadella says Microsoft has "a bunch of chips sitting in inventory that I can't plug in". ERCOT alone has 474 GW of large loads waiting, yet the most new data-center load the US grid has connected in one year is ~10 GW. Every part of the supply chain is backed up: gas turbines take ~6 years, big transformers 2½–4.

We cap AI at 10–25 GW of new capacity a year, which works out to 650–1,700 TWh by 2036. Past ~1,700 TWh, it stops being a question of demand. The turbines, transformers and wires don't exist.

More numbers

  • Amazon's Andy Jassy expects not enough capacity to meet 2026 demand, and Alphabet's CFO calls it "a supply-constrained environment".
  • Northern Virginia's data-center vacancy is 0.2%, and 80% of what's under construction is already leased.
  • About 90% of ERCOT's waiting loads are data centers. Dominion has 54 GW under contract, yet its data-center load grows ~0.5 GW a year.
  • PJM's capacity auction hit its price cap for the third year running and still came up 6.8 GW short.
  • GE Vernova has 116 GW of gas-turbine orders and reservations against ~20 GW a year of output, and turbine prices are up 195% since 2019. A new power plant now waits over 5 years from grid request to operation.
  • Builders are routing around the grid with on-site gas (124 GW announced, half of it speculative), but that hits the same turbine queue.
  • 10–25 GW a year runs from today's pace up to roughly double the entire US generation build. Even the high case falls short of the 50 GW by 2028 Anthropic says the industry needs.
Waiting in line vs. getting built

ERCOT large-load requests474 GW

GE gas turbine backlog116 GW

Dominion data centers under contract54 GW

Most data-center load connected in a year~10 GW

Dominion data-center load added per year~0.5 GW

Years from order to power

Build the data center~1.5

Large transformer2.5–4

Grid interconnection5+

Gas turbine~6

Log scale (top), linear (bottom). Data-center build time: DOE. Others linked in text.

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