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CEHCompute Energy Hour
§ 01 — CEH™ Standardv2.1 · Published April 21, 2026

Compute,
denominated in energy.

Compute Energy Hour (CEH™) is a proposed standard unit for the energy intensity of compute — the facility energy it takes to produce one unit of useful output. One denominator for comparing chips, sites, and claims on energy fundamentals, not GPU-hour pricing alone.

Operating principle — measurement before management

Before we engage —

Which lens are you reading the standard through? It argues in your language.

§ 02Why CEH™ exists

Three numbers. None of them the answer.

AI infrastructure is scaling fast, but no single unit connects hardware performance, facility efficiency, energy price, and carbon. Each common proxy describes only a fraction — buy on one and the others move against you.

kWhEnergy
Counts the power. Blind to the work.
Tells you what a system draws — nothing about the useful compute it returns for it.
FLOPSThroughput
Counts the work. Blind to the cost.
A spec-sheet peak. Says nothing about the energy a real workload burns to reach it.
$/GPU-hrPrice
Counts the rent. Blind to both.
A rate that floats with the market — not a measure of efficiency, and never of carbon.
One denominator that holds all three accountable.
CEH™ resolves energy, work, and outcome into a single comparable unit: the facility energy it takes to produce one unit of useful compute.
§ 03The unit

Compute, expressed in the energy it costs.

Horsepower let buyers compare engines across makers. The BTU made heat a tradable quantity. Each took something everyone argued about and gave it one honest number.

CEH™ does the same for compute — a hardware-neutral unit for the energy a system spends to deliver useful work. It is a measure of energy intensity, not a performance benchmark: lower CEH means more useful compute per unit of energy. Originated and maintained by Oak Ridge Management.

Base definition
CEH = kWh ÷ output
facility energy per unit of useful compute · per hour
Total facility energy drawn over one hour — inclusive of PUE overhead — divided by the useful compute delivered (tokens, TFLOPS, frames, or a declared output unit), at real utilization. Lower is better.
§ 04What CEH™ measures

Four inputs. Three reported figures.

CEH integrates the four variables that materially shape compute economics — hardware power draw, throughput under a declared workload, facility overhead (PUE), and the price and carbon of delivered energy. From one reading it reports three figures.

Figure 01 · Intensity
CEH
kWh / output
The core energy-intensity figure: facility energy per unit of useful compute. Lower is better.
Figure 02 · Economics
CEH Cost
$ / output
CEH multiplied by the delivered price of electricity — the energy cost of a unit of useful compute.
Figure 03 · Emissions
CEH Carbon
gCO₂e / output
CEH multiplied by the carbon intensity of delivered electricity — emissions on the same basis as cost.
§ 05Benchmark methodology

A controlled basis, fully disclosed.

The v2.1 benchmark applies one controlled comparison basis so hardware is assessed like-for-like. A CEH benchmark is reproducible only if it discloses every assumption below.

01
Define
Fixed workload — LLM inference — with output tokens as the declared compute output unit.
02
Meter
Energy measured at the node on an 8-unit basis, then PUE-adjusted to the operating site.
03
Normalize
Across utilization, configuration, and software stack so two readings actually compare.
04
Publish
Versioned, reproducible from disclosed inputs, and open to challenge from any party.
FormulaCEH=Facility energy · kWh, PUE-adjustedUseful compute output→ lower is better
Disclosure requirements — to be reproducible & comparable
  • Hardware configuration — chip model, unit count, TDP
  • Measured utilization during the benchmark window
  • Declared or measured PUE
  • Workload type and compute-output-unit definition
  • Throughput method — software stack and workload parameters
  • Energy rate used for CEH Cost
  • Carbon-intensity source and vintage used for CEH Carbon
§ 06Hardware Reference Registry

What can be compared, and how well it's evidenced.

The Registry is the reference layer — which accelerators can be compared under CEH today, and how strong the public evidence is for each. It is not a certified ranking. It defines eligibility and evidence, not results.

Reference accelerators — CEH™ v2.1
VendorAcceleratorArchitectureDeploymentRoleEvidence
NVIDIAH200 SXMHopperShipping / deployedFrontier inference & trainingAuditable
AMDInstinct MI300XCDNA3DeployedInference, fine-tuning, HPC/AIAuditable
NVIDIAH100 SXMHopperDeployedProduction training & inferenceAuditable
NVIDIAL40SAda LovelaceDeployedCost-sensitive inferenceAuditable
NVIDIAA100 80GBAmpereDeployed / legacy baseExisting-fleet baselineAuditable
GoogleTPU v4TPUDeployed cloudNon-GPU referenceModelable
NVIDIAB200BlackwellFrontier / early rampEmerging frontier platformModelable*
NVIDIARTX 4090Ada LovelaceDeployed (consumer/edge)Non-datacenter comparisonModelable
NVIDIAV100VoltaLegacyHistorical baselineModelable
CPU clusterEPYC-classx86Deployed baselineNon-accelerated floorModelable
Evidence tiers
Auditable
Vendor specs plus public benchmark or deployment data support reproducible CEH modeling.
Modelable
Public hardware data exists, but throughput normalization still depends on declared assumptions.
Modelable*
Relevant and material, but public deployment or benchmark evidence remains incomplete.
§ 07Modeled CEH™ outputs

The benchmark, applied.

Modeled comparative outputs under the v2.1 methodology — not a universal market ranking. Each figure carries the evidence tier of its source hardware and should be read with the assumptions below. CEH is shown indexed to NVIDIA H100 = 100 so it reads at a glance; lower is better.

Accelerator ranking — CEH™ v2.1Provisional · modeled
RankAcceleratorEfficiency Index (H100 = 100)CEH CostCEH CarbonEvidence
01NVIDIA B200 (Blackwell)
S39
0.0294Modelable*
02Google TPU v4
A69
0.04165Modelable
03NVIDIA H200 SXM
A78
0.04187Auditable
04NVIDIA L40S
B83
0.04200Auditable
05NVIDIA H100 SXM
B100
0.05240Auditable
06AMD MI300X
B118
0.06283Auditable
07NVIDIA A100 80GB
C123
0.06294Auditable
08NVIDIA RTX 4090
C193
0.10462Modelable
09NVIDIA V100
D345
0.18825Modelable
10CPU baseline (EPYC)
F986
0.522358Modelable
Grading — by efficiency index (lower is better)S< 50A50–79B80–120C121–200D / F> 200
Benchmark basis
WorkloadLLM inferenceOutput unitoutput tokensNode8 acceleratorsElectricity$0.085 / kWhCarbon0.386 kgCO₂e / kWhUtilization · PUEdeclared per benchmark

CEH indexed to NVIDIA H100 = 100 (lower = better) · CEH Cost in $ / 1M tokens · CEH Carbon in gCO₂e / 1M tokens. Modeled from published specs and public throughput references; third-party-audited public index in development.

§ 08Why it matters

Energy is the largest lever you control.

Under the v2.1 framework, delivered energy price is one of the largest operator-controlled levers in compute economics. Moving from U.S. commercial grid pricing near $0.085/kWh to behind-the-meter generation in the $0.030–0.045/kWh range can materially cut CEH Cost for the same hardware and the same workload.

Hardware choice, facility design, and energy procurement are no longer separable decisions. CEH puts them in one equation.

$0.085$0.030–0.045
per kWh, grid → behind-the-meter
§ 09Governance

A versioned standard, validated in stages.

Versioned
Dated, versioned releases
v2.1 published April 21, 2026. Revisions are versioned — triggered by new workload classes, methodology changes, or new disclosure requirements.
Reproducible
Public-source recalculation
Every figure is reconstructable from disclosed inputs and public specs, so an independent reviewer can re-run it.
Neutral
Energy-source & vendor agnostic
No pay-to-rank. Hardware ranks by the measured numbers, regardless of generation source or commercial relationship.
Validation pathway
1
Provisional
Modeled from public data
2
Verified
Independently recalculated
3
Certified
Third-party audited
§ 10Who it's for

One unit, three rooms.

Operators
Publish efficiency on a standard basis.
Infrastructure operators and cloud providers get a common way to state and compare compute efficiency — across vendors, sites, and hardware generations.
Buyers
Procure on energy economics.
Enterprise buyers evaluate hardware and hosting on cost, efficiency, and carbon at once — not dollars per GPU-hour alone.
Capital
Underwrite on a real denominator.
Capital allocators and infrastructure investors underwrite AI infrastructure on energy fundamentals — efficiency as a line item diligence can defend.

Engage the standard. Or argue against it.

CEH™ is being developed as a measurement and certification framework for compute infrastructure. Bring the hard question — it is built to answer it.

Read the methodology