# AC transmission and Copper

AC transmission needs copper; their prices have moved together.

Source page: https://www.materialinsights.org/links/ac-transmission-and-copper/

[AC transmission](https://www.materialinsights.org/energy/e_hvac/) (energy) and [Copper](https://www.materialinsights.org/commodities/copper/) (commodity): 2 relationships.

## How they are linked

### 1. Material need

*Physical flow · Direct · Copper → AC transmission*

Building or running AC transmission needs copper.

### 2. Price link: windings

*Cost and price · Moderate · Both ways*

Transformer windings are mostly copper. Copper's swings pass into transformer prices slowly through tenders and price adjustment clauses, so the link is weak, at 0.22 for monthly moves and only 0.31 for yearly moves, with copper leading by about one month.

- **0.22** monthly change correlation
- **0.31** 12-month change correlation
- **0.70** fitted elasticity

Built from the site data on production routes, energy flows, industry value chains, input-output tables and prices.