Material Insights · Understanding the Material World

Copper and Distribution grids, mini-grids and interconnectors

Distribution networks are a large copper outlet: copper goes into underground cables, substations, transformer windings and earthing, while aluminium takes most overhead lines. Grid investment, above all in China, was the largest single source of copper demand growth in 2023 and 2024, and programmes such as India's RDSS add to it.

Copper (commodity) and Distribution grids, mini-grids and interconnectors (energy): 4 relationships.

How they are linked

1. Cables, substations and windings

Physical flow · Strong · Copper → Distribution grids, mini-grids and interconnectors

Copper's high conductivity and strength make it the default conductor where space is tight or reliability matters most: underground and building connections, substation busbars, switchgear, larger transformers and earthing.

  • 7.1 million km medium-voltage grid lines installed worldwide (ICA India, 2025)
  • 68.4 million km low-voltage grid lines installed worldwide (ICA India, 2025)

Wood Mackenzie describes copper as scaling across substations and underground connections, while aluminium dominates overhead lines and conductors. So the copper content of a distribution network rises as cities move lines underground and as more substations, switchgear and earthing are added; rural overhead extensions and mini-grid feeders use far less copper per kilometre.

Sources: Mining Weekly; International Copper Association India

2. Aluminium takes overhead and small units

Substitution · Medium · Aluminium can replace copper

Aluminium is lighter and cheaper per unit of conductance, so utilities use it for overhead lines and many small distribution transformers, keeping copper for uses where size, joints or short-circuit strength decide.

  • below 190 kVA rating below which aluminium was found the best winding choice (2010 study)
  • about 25% lower winding weight with aluminium, against about 20% more core weight (2010 study)

The 2010 study found aluminium windings successful in distribution transformers, while large power transformers mostly stay copper. The IEA treats more aluminium in underground cables as a scenario that would cut grid copper demand, so the copper to aluminium price gap shapes how much copper each new kilometre of network uses.

Sources: IEA; IET Electric Power Applications (Olivares-Galván et al.)

3. Grid build-out drives copper demand

Transition · Rising · Grid spending → copper demand

Connecting new users, rooftop solar, heat pumps and chargers needs more and heavier local networks, and metals are a large share of the bill.

  • about 20% share of copper and aluminium in total grid investment costs (IEA, 2021 analysis)
  • more than double rise in copper demand for power lines to 2040, IEA Sustainable Development Scenario (2021 analysis)

The IEA found that the fast expansion of grid investment in China was the single largest factor in copper demand growth over 2023 and 2024. In its 2025 outlook it warned that the mine project pipeline pointed to a possible 30% copper supply shortfall by 2035; the 2026 edition, as reported by Mining.com, narrows this to about 25%. Either way, grid programmes compete with every other copper user for tight supply.

Sources: IEA; IEA; Mining.com

4. Price link: conductor

Cost and price · Weak · Both ways

Switchgear busbars and distribution cables use copper, but switchgear prices are revised rarely and include much labour and electronics, so copper moves barely show up in the price index.

  • 0.04 monthly change correlation
  • 0.04 12-month change correlation
  • 0.56 fitted elasticity

Monthly and yearly correlations of 0.04 mean copper is a cost risk for equipment makers rather than a short-term driver of equipment prices. Metal price clauses in tenders and long delivery times can spread copper swings over many months.

Sources: Material Insights (World Bank, FRED, IMF data)

For investors

Key learnings

  1. Distribution networks are a structural copper buyer, and grid investment in China was the largest single source of copper demand growth over 2023 and 2024.
  2. Aluminium caps copper intensity in overhead lines and small transformers, so the copper to aluminium price gap matters for grid copper demand.
  3. Equipment prices hardly follow copper month to month, correlating at 0.04, so margins of cable and switchgear makers carry the metal risk unless contracts pass it on.

What to track

  • Grid capital spending by utilities (China State Grid, Indian discoms, European DSOs): Higher budgets lift medium-term copper cable and switchgear demand (Quarterly · utility results and regulators)
  • Copper to aluminium price ratio: A wider ratio pushes utilities and cable makers towards aluminium (Daily · LME)
  • Cable maker order books and metal pass-through clauses: Shows whether copper cost is reaching buyers or squeezing margins (Quarterly · company results)

For policymakers

Key learnings

  1. India's RDSS has an outlay of Rs 3,03,758 crore, and about Rs 1,46,465 crore of loss reduction works had been sanctioned by November 2024, a large call on cables, conductors and transformers.
  2. Allowing aluminium where it is technically sound, in overhead lines and small transformers, lowers copper import needs without hurting reliability.
  3. The IEA expects a copper supply shortfall of about 25 to 30% by 2035 (its 2025 and 2026 outlooks), so grid plans should be checked against metal availability and the recycling of old conductors.

What to track

  • RDSS sanctioned versus completed loss reduction works: Pace of network spending that turns into cable and transformer orders (Quarterly · Ministry of Power)
  • Copper import volumes and prices: Exposure of grid programmes to imported metal (Monthly · Ministry of Commerce trade data)
  • AT&C loss levels of discoms: Whether network investment is cutting losses towards the 12 to 15% target (Annual · PFC and Ministry of Power)

India

India's copper demand rose 13% to about 1,700 kt in FY2024, with about 75% going to electrical uses; conventional generation, transmission and distribution took about 26% of India's cable demand. The Rs 3,03,758 crore RDSS, aimed at cutting AT&C losses to 12 to 15%, adds to this pull.

Sources

  1. The Role of Critical Minerals in Clean Energy Transitions (revised March 2022), copy hosted by the Resolution Copper EIS library, IEA (2022)
  2. Grid infrastructure requirements reshape base metals demand outlook to 2040: WoodMac, Mining Weekly (2026)
  3. Copper's Key Role in Cables, International Copper Association India (2025)
  4. Lok Sabha unstarred question 595: Revamped Distribution Sector Scheme, Ministry of Power, Government of India (2024)
  5. Selection of copper against aluminium windings for distribution transformers, IET Electric Power Applications (Olivares-Galván et al.) (2010)
  6. Price correlation, Material Insights, Material Insights (World Bank, FRED, IMF data)
  7. Global Critical Minerals Outlook 2025 (extract, copy hosted by the University of Texas), IEA (2025)
  8. Acid test: IEA warns copper supply outlook has worsened considerably, Mining.com (2026)