Nuclear is back. Surging electricity demand from AI data centers, reshoring, and electrification is colliding with grid reliability imperatives and decarbonization commitments. More than 30 countries have pledged to triple nuclear capacity by 2050. In the US, President Trump's 2025 executive orders target a quadrupling of nuclear generating capacity. Global nuclear investment is forecast to reach $2.2 trillion over the next 25 years.

But enthusiasm is not execution. For the small number of capital allocators who must actually write the checks—such as utility executives, infrastructure fund managers, hyperscalers, sovereign sponsors, and independent power producers—moving from press release or planning assumption to final investment decision (FID) is the most consequential capital decision most will ever face. It is also one that many struggle to make for reasons that compound on each other.

• Scale without precedent: Capital commitments of $10 billion to $30 billion (or more) can exceed any single project or program in the company's history and dwarf the typical capital project by an order of magnitude.
• Timelines that outlast leadership: Construction spans 7 to 12 (or more) years. The executive who breaks ground may not be the one who cuts the ribbon.
• Technology in flux: Multiple potential nuclear technologies, a well-funded fusion ecosystem, and advanced geothermal are all competing for the same "firm clean power" allocation, yet cost discipline demands a decade-plus commitment to a single reactor design. Technologies range widely in maturity, from proven gigawatt-scale designs to concepts still in licensing.
• Immature supply chains: Decades without Western new builds have atrophied the nuclear-qualified workforce, component suppliers, and heavy construction base. Supply chains lack the available scale today, requiring innovative approaches.
• Regulatory and political volatility: Nuclear projects unfold across decades; political mandates operate on four- to five-year cycles. Administrations change. Policies shift midstream.
• Institutional memory gap: Most organizations are a generation removed from their last nuclear build. The muscle memory is gone, and megaprojects are fundamentally different from large projects in their organizational complexity and fragility.

The upside is generational: 60 to 80 (or more) years of dispatchable, low-carbon, near-zero, marginal-cost baseload power. The downside is well documented: Vogtle's two AP1000 units exceeded $35 billion, more than double the original estimate, and took 14 years instead of 7 years. Southern Company's stock underperformed for years during the construction overhang as it worked through the implications from the Fukushima nuclear accident and Westinghouse bankruptcy, but it has improved markedly since the plants were commissioned. Also, VC Summer was abandoned after $9 billion in sunk costs.

This is not a decision that can be reasoned through in a boardroom; it must be earned through structured work.

The global evidence is clear: What kills projects and what saves them

Bain's experience and research across geographies and reactor types finds a consistent pattern. Projects do not fail because the reactor technology doesn't work; they fail because the program around the reactor wasn't ready.

The EPR experience is instructive. Flamanville 3 in France, Olkiluoto 3 in Finland, and Hinkley Point C in the UK did not fail on one dimension alone. They started construction with designs that were insufficiently ready for execution, then compounded this with a lack of program thinking, supply chains of insufficient capacity and capability, and owner and contractor organizations with limited institutional experience of true megaproject delivery. Late design changes, regulatory reinterpretation, rework, and concrete placement failures cascaded into massive cost and schedule escalation, a pattern that repeated across three countries and three decades.

By contrast, the UAE's Barakah program deployed a mature APR-1400 reference design—critically, a technology with already proven design maturity—with replication discipline and a tightly integrated engineering, procurement, and construction (EPC) contractor/supplier ecosystem. China's AP1000/CAP1000 fleet tells a similar story: The first series took nearly as long as Vogtle, but the second achieved dramatic schedule reductions, demonstrating that learning curves are real but only when the program is designed to capture them. Chinese leaders have been explicit about their model: As they recently told a utility in Europe, "we just copied what you did many years ago."

That original French fleet with several reactors per year under simultaneous construction throughout the 1970s and 1980s remains the gold standard of programmatic execution. Even at gigawatt scale, the industrial rhythm of a fleet approach meant that skills, supply chains, and institutional knowledge never atrophied between units. The lesson: Schedule discipline creates cost discipline. In nuclear construction, time is both wasted capital expenditures and lost returns.

If you deliver on schedule, you have a chance to deliver on cost. If you do not deliver on schedule, you have zero chance.

These lessons are portable and proven. But they must be embedded into the program before FID, not applied as corrective measures once problems emerge.

Pre-FID: An integrated program of work, not a technology selection exercise

Many nuclear players will instinctively map nuclear work onto familiar processes: technology selection or perhaps power generation project development. But technology selection—that is, choosing a reactor design—is only one input to the FID decision. Traditional project development work, similarly, is at a different scale of complexity and risk for nuclear. A pre-FID program must go far beyond these traditional approaches, integrating business case validation, delivery readiness, and financing strategy into a single, governed, cross-functional effort. It is this integration and discipline that many programs lack.

A credible nuclear FID requires proving three interlocking propositions in parallel:

• The business case creates durable value.
• Delivery risks are identified and credibly mitigated.
• The program can be financed.

The business case must create durable value for customers, investors, and regulators across a wide range of scenarios, not just the base case. This means rigorous system economics modeling (levelized cost of energy, project financing, scenario analysis), honest stress-testing against alternative generation portfolios, and a clear articulation of the asset's role in the evolving energy mix, including its value as a dispatchable, low-carbon baseload in a grid with growing intermittent renewable penetration.

Delivery risks must be identified and credibly mitigated, not assumed away. This encompasses bottom-up cost and schedule validation; supply chain and contractor readiness assessments, with proactive risk mitigation plans; technology selection and design maturity verification; workforce strategy and operating model design; and construction execution planning, including the digital and systems infrastructure required for effective project controls at megaproject scale.

The program must be financed durably in a structure that sustains investor confidence through a decade-plus construction period. This requires capital structure optimization, risk allocation across technology providers/operators/capital partners, investor positioning and communication strategy, and, critically, engagement with governments that have played a role in enabling every successful nuclear program over the past two decades, whether through loan guarantees, regulated asset base models, contracts for difference, or overrun protection. Financing architecture must be designed to absorb the inevitable surprises.

These three propositions cannot be validated in sequence. They interact. A design change affects the cost estimate, which changes the financing requirement, which alters the investor proposition, which may require a different risk-sharing structure, which loops back to the EPC contracting model. The pre-FID program must be governed as an integrated whole, and it must be evergreen, evolving as facts change over the two-to-five-year maturation period. Companies will need to demonstrate significant rigor at FID while navigating multiple gates involving significant funding releases to do the work required to get to FID.

This integration work—namely, combining business case, delivery readiness, and financing into a coherent, continuously updated decision framework—is a critical missing element in many nuclear programs today. Dozens of major interdependent work packages must be executed in parallel. It requires thoughtful governance, cross-functional coordination that cuts through organizational silos, and constructive collaboration between owners, OEMs, supply chain participants, regulators, and financiers.

The path differs by capital allocator, but the discipline does not

In the US, utilities average around a 10% return on equity across the regulatory compact. New nuclear must compete on a risk-adjusted basis against transmission, distribution, and other generation investments, all funded by a common equity base that is structurally designed for low-risk, predictable earnings growth. The same fundamental tension applies across regulated and semi-regulated models in Europe and other OECD markets whether under traditional cost of service, regulated asset base, or contract for difference frameworks, all of which involve government backing in some form. For these players, demonstrating affordability and durable cost recovery mechanisms, securing sustained political and community support (which must survive multiple election cycles), and ensuring that the organization can scale delivery capabilities that it hasn't exercised in a generation are critical.

Infrastructure investors, by contrast, operate under defined return horizons and capital recycling expectations that are fundamentally mismatched with nuclear's timelines. Many lack direct nuclear construction or operating experience. The work centers on risk allocation frameworks and partnerships, contracted revenue structures that reduce merchant exposure, exit pathway clarity and valuation inflection points, and governance structures that compensate for limited in-house nuclear capability.

Pre-FID work must be tailored to focus on the biggest, most comprehensive risks to the investment thesis for the developer.

Getting to a responsible "yes"

For any leadership team, launching a new nuclear program is among the most consequential decisions they will make for the company, its customers, its investors, and the communities it serves. The evidence from global experience is unambiguous: Organizations that successfully deploy nuclear do so through thorough, disciplined preparation, not optimism.

The work starts years before FID. It cuts across every function. It requires governance structures that most organizations don't yet have. And it demands that facts be confronted honestly, that red flags be surfaced early, that mitigation plans be developed deliberately, and that the assessment remain evergreen as conditions evolve.

The good news: The failure and success patterns are well documented. The best practices are battle-tested. The question is whether leadership teams will comprehensively implement those best practices to meaningfully improve the chances of success for their proposed nuclear projects.