Power, cooling and electrical equipment
The Stack Capacity Index measures how much an entity shapes the world's AI capacity within its layer of the stack. It is built mostly from measured, sourced facts, each scored on the board's own scale; stated estimates of AI exposure, position and momentum, scored on one written rubric, add to them but never outweigh a row's own facts. A figure nobody publishes is left out, never estimated.
AI exposure reads how much of the business serves AI compute demand today. It is a stated estimate.
Scores run 0 to 100. The top 10 companies · updated 21 Oct 2026.
| 01 |  Schneider Electric | Power distribution & UPS | 83.7 | 50.0 |
| 02 |  Vertiv | Power distribution & UPS | 74.9 | 80.0 |
| 03 | Comfort Systems USA | Electrical contractors & EPC | 58.7 | 55.0 |
| 04 | EMCOR | Electrical contractors & EPC | 56.5 | 25.0 |
| 05 | Wesco International | Electrical distribution | 55.5 | 22.0 |
| 06 |  Siemens (Smart Infrastructure) | Power distribution & UPS | 54.7 | 15.0 |
| 07 | Legrand | Power distribution & UPS | 52.5 | 50.0 |
| 08 |  ABB | Power distribution & UPS | 50.9 | 28.0 |
| 09 |  Hitachi (Hitachi Energy) | Transformers & grid equipment | 46.7 | 18.0 |
| 10 | Caterpillar | Backup generation | 46.3 | 15.0 |
Index scores are model outputs, not predictions. The facts behind each score are sourced, and the estimates are stated with their basis in the full dataset, where figures resting on a secondary source are marked.