Nucor $492M Indiana Investment & AES Rate Fight | TEG Daily September 18, 2026

Nucor has now committed $492 million across four Indiana projects since 2021, and today's brief covers four connected developments that Indiana plant leaders need to track before January. A new steel grating line in DeKalb County reshapes supplier bundling. A $71 million AES Indiana rate fight has a January implementation date regardless of what regulators decide at the March 2027 hearing. Q3 guidance from two of Indiana's largest steel producers is sending a pricing signal that raises input costs for every manufacturer buying sheet steel. And a federal aluminum tariff window closes in 16 months with no domestic supply solution in sight.

Questions for Your Morning Huddle

Q: What does the Nucor Vulcraft DeKalb County expansion mean for Indiana steel grating buyers?

A: When the new facility is complete, Vulcraft Indiana will be the only Midwest campus supplying joists, joist girders, deck, and grating from a single order. Standalone grating distributors cannot replicate that bundling from one location, which changes your pricing and lead-time leverage if you're sourcing from a regional competitor.

Q: When does AES Indiana Phase 2 take effect and what is the industrial rate impact?

A: Phase 2 takes effect in January 2026, the OUCC did not seek a stay, so the March 2027 rehearing does not block implementation. Industrial customers should model a 3 to 4% rate increase on top of the Phase 1 impact that took effect July 27.

Q: What do the Nucor and Steel Dynamics Q3 guidance misses signal for Indiana steel buyers?

A: Two of the largest Midwest EAF producers guiding below consensus on the same day signals that the tariff-driven pricing ceiling may be closer than the market assumed, but Midwest hot-rolled coil is still trading near $1,223 per short ton, up 35 to 50% from its 52-week low. Your inbound steel cost is higher; the question is how much runway remains for further increases.

Q: What happens to aluminum tariffs in January 2028 and why does it matter for Indiana manufacturers?

A: The July 2026 executive action cut the Section 232 aluminum rate from 50% to 25% for companies committing to domestic smelter construction, but that conditional rate expires automatically on January 1, 2028. No new U.S. primary smelter can be operational before the mid-2030s given build timelines. Tier 1 and Tier 2 auto suppliers with aluminum input costs face a hard reset in 16 months, secondary recycled aluminum processors may be the only realistic near-term sourcing alternative.

Three Actions for This Week

Audit every supply contract that carries aluminum input costs through 2028 and identify which ones assume the 25% conditional Section 232 rate.

If your facility is in the AES Indiana service territory, model a 3 to 4% industrial rate increase taking effect in January alongside Phase 2, and model what a full settlement rollback means for AES capital spending on grid reliability through 2030.

Contact a secondary aluminum supplier and get a comparative cost quote before the tariff window resets.

All three cost vectors: rising steel input costs, a contested power rate increase with a January implementation date, and a hard-expiring aluminum tariff window, arrive at the same 12 to 18-month horizon. If your supply contracts, energy cost model, and tariff exposure aren't stress-tested through early 2028, this is the week to start.

For more on how the AES Indiana rate case affects industrial electricity costs, see the TEG Daily coverage of the AES Indiana rate case and the IURC commissioner firing and the September 11 brief on AES Indiana rate case timing and aluminum tariff job risk.

For the demand charge and rate structure fundamentals that sit behind any AES rate increase, the canon post on demand charges for commercial and industrial facilities covers how those line items are calculated and where industrial exposure concentrates.