Datacenters are eating electricity at a frightening pace. The IEA sees global datacenter power demand more than doubling, from 415 TWh in 2024 to 945 TWh by 2030. But America's grid is old: over 70% of its large transformers are more than 25 years old, and a new one takes about three years to arrive. So Big Tech builds gas plants next door, or bolts giant batteries (ESS) onto solar. ESS demand is climbing, and until now more than 90% of those batteries were Chinese. Washington has now moved on three fronts. First, MACR: to earn the clean-energy tax credit you must cut the Chinese share (for ESS, below 45% in 2026, below 25% by 2030). Second, tariffs: the rate on Chinese ESS batteries rose from 40.9% to 58.4% starting in 2026. Third, AMPC: make the cell in America and you get $35 per kWh back. Stack the three, and the gap between tariff-inflated Chinese cells (about $87/kWh) and Korean cells built in the US ($85-90) vanishes; add the subsidy and the Korean cell drops to $50-55. SNE Research expects the Korean share of US ESS batteries to jump to 61% in 2026 and 85% in 2027. The catch: Korea's three makers are still in oversupply, so they must convert this window fast.
Why it matters · Trump gets cursed by the very firms he's helping. The broad China-containment push has handed Korea's battery trio a gift called price competitiveness; the open question is how much of their oversupply they can push through that window before it narrows.
Worth asking · If you could buy just one of the battery trio, which?