Alva Energy, in collaboration with Idaho National Laboratory (INL), Oak Ridge National Laboratory (ORNL), and MIT, has published a new analysis for the U.S. Department of Energy examining how costs and construction schedules for large nuclear plants can decline with repeated builds under strong project management organizations.

The report, Potential Cost Reduction in New Nuclear Deployments Based on Recent AP1000 Experience, analyzes construction data from every AP1000 project built to date in the United States and China. The findings challenge the prevailing assumption that large light-water reactors cannot be delivered on competitive timelines — and rebut the idea that first-of-a-kind (FOAK) costs permanently define the economics of new nuclear builds.

A key finding of the study is that construction timelines for AP1000 reactors have fallen by nearly 50% in China’s second build series—demonstrating that disciplined project management and systematic integration of lessons learned, not reactor size, determine nuclear build speed.

Using publicly available milestone data — including module placements, reactor vessel installation, first criticality, and grid connection — the team compared the first AP1000 series in China (Sanmen and Haiyang) with the ongoing second series of CAP1000 and CAP1400 projects. The results show a 48% reduction in average duration from first nuclear concrete to major milestones, a 42% reduction in average time between construction milestones, and a 60% reduction in schedule variance, indicating far greater predictability. Shidao Bay Unit 1 (CAP1400), for example, reached grid connection in approximately 5.3 years — compared to roughly 9 years for first-series AP1000 units. Ongoing second-series CAP1000 projects are targeting total construction durations of 4.5–5 years.

These results demonstrate Alva’s founding thesis: the limiting factor in new nuclear deployment is not reactor technology — it is execution. Where project management institutions are strong and learning is deliberately applied, construction timelines shorten and variance collapses. Alva’s nuclear power uprate program applies the same principles, leveraging standardized designs, repeatable engineering packages, disciplined regulatory preparation, and fleet-wide learning to unlock gigawatts of additional, cost-effective clean power from existing reactors.

Read the full report here.

And listen to Alva CEO James Krellenstein discuss AP1000 construction experience on the podcast Decouple.