Westinghouse eVinci Microreactor Hits Criticality Milestone with Cameco Support

Key Facts

1Westinghouse, 49% owned by Cameco Corp, achieved initial criticality for its 5 MWe eVinci microreactor.

2Zero-power criticality testing was completed at the Nevada National Security Site alongside DOE national laboratories.

In a move reflecting the growing momentum for advanced nuclear energy solutions, Westinghouse has announced achieving initial criticality for its 5 MWe eVinci microreactor. According to reports, zero-power criticality testing was successfully completed at the Nevada National Security Site in collaboration with U.S. Department of Energy national laboratories. This milestone is a fundamental step in developing portable nuclear batteries designed for decentralized power in commercial and military applications.

These developments are of direct importance to Cameco Corp (CCJ), which holds a 49% stake in Westinghouse, strengthening its position in the clean tech sector. Per market data, CCJ shares closed at $106.33 on August 27, 2026, while 0R35.L stood at 147.85 on the same date. This technical progress comes as the nuclear energy sector seeks to reclaim its role as a cornerstone in the global transition toward sustainable energy.

Investors should monitor CCJ price levels following its recent close at $106.33 (close August 27, 2026), as it trades near its daily low of $105.14. While focus remains on microreactor deployment progress, recent economic data shows U.S. GDP growth slowed to 1.5% in the latest quarter, which may influence risk appetite within the heavy industrial tech sector.