Most of the copper at an EV charging station is not inside the chargers. It is in the supply wiring: feeders from the panel or transformer, branch circuits to each charger, and the grounding system. In a hypothetical four-charger Level 2 site with 30 m circuits, the branch wiring alone can hold around 48 kg of copper, compared with roughly 2 kg in each charger cable.
Key Takeaways
- Most site copper is in feeders, branch circuits and grounding.
- A hypothetical four-charger Level 2 site has about 48 kg in branch wiring.
- Run length and voltage drop drive copper use.
- DC fast sites use far more copper per charger.
Where the Copper Sits at a Charging Site
| Part of the site | Copper role | What sets the amount |
|---|---|---|
| Utility transformer and service | Windings and busbars (often utility-owned) | Site capacity |
| Feeders and switchboard | Large conductors and busbars | Total load, distance, code tables |
| Branch circuits to chargers | Line, neutral or second line, and equipment ground | Charger current, run length, voltage drop |
| Grounding and bonding | Ground conductors, bonding jumpers, electrodes | Local code and site design |
| Charger cables | Power, earth and signal cores | Rating and cable length |
| DC fast charger cabinets | Transformers, inductors, busbars, heavy cables | Power level and cooling design |
Worked Example: Four Level 2 Chargers
Assume four 48 A chargers. EV charging is a continuous load, so each circuit is sized at 125% of charger current, giving a 60 A circuit. Assume each run is 30 m and uses three 6 AWG copper conductors (13.3 mm² each) plus a 10 AWG ground (5.26 mm²). These sizes are assumptions for illustration only; your electrician sizes conductors from the code tables, terminal ratings and voltage drop.
- Copper area per run: 3 × 13.3 + 5.26 = 45.2 mm².
- Volume per run: 0.452 cm² × 3,000 cm = 1,356 cm³.
- Mass per run: 1,356 × 8.89 g/cm³ ≈ 12 kg.
- Four runs: about 48 kg, before feeders, panels and grounding.
- Four 25 ft charger cables: roughly 2 kg each, or about 8 kg.
Longer runs raise copper in direct proportion, and voltage drop may push conductors up a size. That is one reason trenching distance features in commercial installation costs. Load management can reduce the feeder size a site needs, as covered in load calculation basics.
DC Fast Charging Sites
DC sites concentrate much more copper per charger. Power conversion happens in the station, so cabinets include transformers and inductors, and the output cables carry hundreds of amps. Our explainer on how DC fast chargers work shows the power path. The U.S. Department of Energy cites DC fast charger installation at about $20,000–$60,000, and conductors are one part of that.
What Site Owners and Distributors Should Do
- Place chargers close to the supply to shorten runs.
- Ask the electrician for conductor schedules early so copper cost is in the budget.
- Consider shared-power chargers to avoid oversizing feeders.
EVDANCE supplies commercial AC units such as the EV-AC03201T dual-connector AC station, where two connectors share up to 43 kW from one supply, and compact DC models like the EV-RHDC30K-L. See our commercial solutions.
Frequently Asked Questions
Is there more copper in the charger or in the wiring?
At most Level 2 sites, the wiring holds more. Each circuit can contain several times the copper in the charger cable.
Can aluminium feeders reduce copper use?
Aluminium is used for some larger feeders when sized and terminated to code. Charger cables and terminals stay copper.
Who owns the copper in the transformer?
Often the utility, if it supplies the transformer. Check the service agreement.
Related Reading
- How Much Does It Cost to Install a Commercial EV Charging Station?
- Adding EV Chargers to a Building: Load Calculation Basics
- How Do DC Fast Chargers Work?
- How Do EV Charging Stations Work?
