HI-STORM

Operational
Holtec International
Holtec International
HI-STORM

Overview

Industry-leading dry cask storage system for spent nuclear fuel - the most widely deployed system of its kind worldwide.

In commercial operation across Holtec's global dry storage business, which served 155 reactors worldwide by the end of 2025 and continues to expand with new projects in Asia and Europe.

Key Specs

Reactors Served

155 worldwide

System Type

MPC-based dry storage and transport platform

U.S. Output Share

~75% of U.S. reactors (70 of 94, as of Jun. 30, 2026 per the August 2026 S-1/A); Holtec also holds 90%+ share of the separate U.S. wet-storage market

Domestic Market Share

~75%

Global Deployment

U.S. and international nuclear plant sites