Westinghouse pushes its eVinci microreactor through high-temperature criticality testing in Nevada, clearing a major technical milestone for the compact reactor
In the latter phase of the year, most of the projects that started off at the beginning of 2026 are now being wrapped up, meaning the general population can look forward to receiving surplus clean electricity. The United States has maintained its stance of diversifying the energy portfolio of every state in order to guarantee that there is reliable clean electricity everywhere throughout the year. According to the latest news, Westinghouse has pushed its eVinci microreactor through high-temperature criticality testing in Nevada, clearing a major technical milestone for the compact reactor.
Westinghouse Electric Company continues to improve the United States’ nuclear sector
The United States spent many years being viewed as the pinnacle of nuclear energy generating strategies before the nation veered off a bit. However, with the clean energy transition now underway, the U.S. is demonstrating why it must be respected as a nuclear energy powerhouse. Westinghouse Electric Company is a pioneer in the global nuclear energy industry, tracing its roots back to the alternating current (AC) electricity system commercialized by George Westinghouse in 1886.
The entity was started by George Westinghouse in Pittsburgh, Pennsylvania, as the Westinghouse Electric & Manufacturing Company. Its ability to exist from the 1800s all the way into the 2020s is a testament to the company’s ability to adapt to the newest nuclear energy generation strategies.
The entity has contributed massively to the United States’ economic landscape from an energy perspective, as it employs over 12,500 people across 21 countries, with technology underlying almost half of the world’s operating nuclear reactors.
Westinghouse pushes its eVinci microreactor through high-temperature criticality testing
Westinghouse built the world’s first commercial pressurized water reactor in 1957 in Shippingport, Pennsylvania. Since then, the company has gone on to execute even more captivating initiatives such as developing the AP1000 large-scale nuclear plant and the innovative eVinci microreactor. According to a recent press release from Westinghouse, the company has completed zero-power high-temperature criticality testing for its eVinci microreactor.
There was a tremendous amount of excitement from the energy industry following the announcement, as people understood it as a massive milestone in the program’s build-test-learn development journey. The nuclear energy sector has transformed drastically ever since the integration of technology, with companies now having a greater ability to execute ambitious projects.
The latest work was completed in partnership with Los Alamos National Laboratory and the Nevada National Security Site (NNSS) at the National Criticality Experiments Research Center (NCERC), a National Nuclear Security Administration (NNSA) capability in Nevada.
Unpacking the specific details of the high-temperature criticality testing
The company’s announcement revealed that on September 3, 2026, the eVinci test reached criticality at 663°C, and Westinghouse researchers successfully made a subcritical reactivity measurement at a peak core temperature of 1,011°C, a record high temperature for a reactivity measurement at NCERC.
These achievements generated high-quality, temperature-dependent data to strengthen analytical models further and quicken prototype design. The initiative is a continuation of the experimental work started with the recent eVinci zero-power criticality testing and progresses the understanding of how the eVinci design behaves as representative materials are heated toward operating conditions.
The milestone displays Westinghouse’s iterative, evidence-based development model that lessens the risk and provides greater confidence in the performance, cost, and deployment of the eVinci technology.
Looking ahead: The expected importance of Westinghouse’s reactor technology
Following the company’s latest run of momentum, there are huge expectations for it to shape the future of nuclear development. Dan Sumner, Westinghouse President and Chief Executive Officer, stated the following:
“For nearly a century, Westinghouse pioneers have not waited for the future of nuclear energy – they have engineered it. This milestone brings that same spirit to the eVinci program. Our teams are rapidly building, testing, learning and improving advanced nuclear technologies, turning uncertainty into validated evidence.”
The general population usually only gets to experience projects after they have reached completion without understanding the complexities that go into the execution of a project. Westinghouse is showing people the hurdles involved in project execution.
Prince is a versatile writer focused on energy, automotive, environmental, and general news topics. He makes complex technical and policy issues clear, engaging, and accessible for a broad audience.
