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Materials & the Replacement Clock

The renewable build has already moved ~21 million tonnesof material (see the homepage counter). But the honest question isn't the total — it's the intensity per unit of energy, and the fact that none of it is dug up only once.

Critical minerals per terawatt-hour

Lead with per-TWh, not per-megawatt — it bakes in the capacity-factor gap (solar runs ~23% of the time, nuclear ~92%). On that fair basis, a wind or solar TWh needs ~10× the critical minerals of a nuclear one.

Offshore wind
200 t
Onshore wind
130 t
Solar PV
124 t
Nuclear
12 t
tonnes of critical minerals per TWh of lifetime generation · IEA, via World Nuclear Association

Honesty rail: this is critical minerals only— it deliberately excludes steel, concrete and aluminium, which dominate tonnage by mass (the homepage counter shows those). The IEA's own "wind needs 9× the minerals of a gas plant" headline uses this same critical-minerals basis. And the chokehold on these minerals is midstream refining, not mining.

The replacement clock

A reactor runs 60–80 years. A renewable grid is rebuilt two to three times over that span — and because Australia recycles almost none of it, each rebuild is fresh mining, not a closed loop.

Solar inverters
10–15 yr
The first thing to fail. The 2010s rooftop boom is already replacing them.
Grid & home batteries
10–15 yr
Degrade with every cycle; the storage fleet is replaced ~2× per panel life.
Wind turbines & blades
18–25 yr
Blades are thermoset composite — largely landfilled, then rebuilt.
Solar panels
25–30 yr
Australia's ~28 GW rooftop fleet comes due for replacement from ~2035.

These tonnes are not one-and-done: panels are re-procured ~every 25 yr, inverters ~15 yr, blades ~20 yr — and Australia landfills most end-of-life panels and nearly all blades, so replacement is fresh mining, not a closed loop.