The US is cutting China out of its power grid supply chain, and that is good news for Taiwan's four big heavy electrical equipment makers.

• Washington now treats transformers, transmission lines, high-voltage breakers and control systems as national defense resources, and in August tightened rules on foreign-made grid gear over security worries about its software and digital parts.
• America can't build enough of this equipment itself — big transformers take years to make — while aging grids and a rush of new data centers are driving demand up fast.
• Taiwan's Hwa Cheng, Shihlin Electric, Chung-Hsin Electric and Allis are each pushing into North America with transformers, switchgear, distribution equipment and power engineering work.
• Cheap Chinese gear used to win on price; now security and where the equipment comes from matter more than the sticker price.
• The US needs Taiwan, Japan, South Korea and Europe to fill the gap, so certification and local service presence are the things to watch.

Outlook: Expect more orders to flow to non-Chinese suppliers as US restrictions tighten, with Taiwanese firms racing to expand capacity and win certifications.