---
type: claim
domain: energy
description: "Large nuclear consistently overruns budgets (Vogtle 3&4: $35B vs $14B estimate). SMRs promise factory fabrication, modular deployment, and shorter timelines. NuScale, X-Energy, Kairos, and others target first commercial units late 2020s-early 2030s, but none have operated yet."
confidence: experimental
source: "Astra; NuScale FOAK cost data, Lazard LCOE v17, DOE Advanced Reactor Demonstration Program, Lovering et al. 2016 Energy Policy, EIA Vogtle cost reporting"
created: 2026-03-27
secondary_domains: ["manufacturing", "ai-alignment"]
depends_on:
  - "AI datacenter power demand creates a 5-10 year infrastructure lag because grid construction and interconnection cannot match the pace of chip design cycles"
challenged_by:
  - "NuScale's cost estimates have already escalated significantly before first operation, suggesting SMRs may repeat large nuclear's cost disease"
  - "Solar-plus-storage may reach firm power economics before SMRs achieve commercial deployment"
---

# Small modular reactors could break nuclear's construction cost curse by shifting from bespoke site-built projects to factory-manufactured standardized units but no SMR has yet operated commercially

Nuclear fission's core problem is not physics but construction economics. Large reactors consistently overrun budgets and timelines: Vogtle 3&4 in Georgia came in at roughly $35B versus the original $14B estimate and 7 years late. Flamanville 3 in France: 12+ years late, 4x over budget. Olkiluoto 3 in Finland: similar. The pattern is structural — each large reactor is a bespoke megaproject with site-specific engineering, first-of-a-kind components, and regulatory processes that reset with each build.

SMRs (Small Modular Reactors, typically <300 MWe) propose to break this pattern through:
- **Factory fabrication**: build reactor modules in a factory, ship to site, reducing on-site construction complexity
- **Standardization**: identical units enable learning-curve cost reduction across fleet deployment
- **Smaller capital outlay**: $1-3B per unit vs $10-30B for large reactors, reducing financing risk
- **Flexible siting**: smaller footprint enables colocation with industrial loads (datacenters, desalination, hydrogen production)

The AI datacenter demand surge has accelerated SMR interest: Microsoft signed with X-Energy, Amazon invested in X-Energy, Google contracted with Kairos Power, and the DOE's Advanced Reactor Demonstration Program is funding multiple designs. The thesis is that datacenter operators need firm, carbon-free power at scale and are willing to be anchor customers.

But no SMR has operated commercially anywhere in the Western world. NuScale — the furthest along with NRC design certification — saw its first project (Utah UAMPS) canceled in 2023 after cost estimates rose from $5.3B to $9.3B. The fundamental question remains open: can factory manufacturing actually deliver the cost reductions that theory predicts, or will nuclear-grade quality requirements, regulatory overhead, and first-of-a-kind engineering challenges repeat the large reactor cost pattern at smaller scale?

## Challenges

Russia and China have operating small reactors (Russia's floating Akademik Lomonosov, China's HTR-PM), but these are state-funded without transparent cost data. NuScale's cost escalation before even breaking ground is a warning signal. The 24% solar learning rate and declining battery costs mean the competition is a moving target — by the time SMRs reach commercial operation in the late 2020s-early 2030s, solar+storage may have reached firm power economics in most markets. SMR licensing still requires NRC review per site even with certified designs, adding time and cost. The manufacturing supply chain for nuclear-grade components doesn't exist at scale and must be built.

---

Relevant Notes:
- [[AI datacenter power demand creates a 5-10 year infrastructure lag because grid construction and interconnection cannot match the pace of chip design cycles]] — SMRs are one proposed solution to the datacenter power gap
- [[fusion contributing meaningfully to global electricity is a 2040s event at the earliest because 2026-2030 demonstrations must succeed before capital flows to pilot plants that take another decade to build]] — SMRs address the gap between now and fusion availability
- [[the atoms-to-bits spectrum positions industries between defensible-but-linear and scalable-but-commoditizable with the sweet spot where physical data generation feeds software that scales independently]] — nuclear manufacturing is deep atoms-side, learning curves apply differently than software

Topics:
- energy systems
