How Nuclear Energy Works: Enrichment, Fuel, and the Geopolitics of Atomic Power
Understanding the infrastructure that turns uranium into electricity — and why nuclear facilities have become frontline targets in energy warfare.
Nuclear power plants generate roughly 10% of global electricity, but the infrastructure behind them — uranium enrichment, fuel fabrication, reactor operations — forms a complex supply chain that sits at the intersection of energy security and proliferation risk.
Recent strikes on nuclear facilities in the Middle East have thrust this infrastructure into sharp focus. What was once a peripheral concern in energy policy is now a frontline issue, as states weaponise attacks on reactors, enrichment sites, and fuel supply chains. Understanding how Nuclear Energy works — from mine to megawatt — is essential to grasping why these facilities matter and what their vulnerability means.
The Nuclear Fuel Cycle: Mine to Reactor
Nuclear energy begins with uranium ore, mined primarily in Kazakhstan, Canada, and Australia. Natural uranium contains just 0.7% of the fissile isotope U-235 — the variant that splits easily to release energy. Most reactors require fuel enriched to 3-5% U-235, a process that separates isotopes using high-speed centrifuges.
Enrichment is the critical chokepoint. According to the World Nuclear Association, global enrichment capacity stands at roughly 70 million separative work units (SWU) per year, with Russia controlling 46% of that capacity. China, France, the UK, and the US account for most of the remainder. Iran operates centrifuges at Natanz and Fordow, enriching to 60% U-235 — a level with no civilian justification and just a technical step from weapons-grade 90%.
Enriched uranium is converted into ceramic pellets, loaded into fuel rods, and bundled into assemblies. A single fuel assembly for a pressurised water reactor contains roughly 200 rods, each holding 180-270 pellets. One pellet — the size of a fingertip — generates as much energy as one tonne of coal. Fuel assemblies are loaded into the reactor core, where controlled fission heats water to drive turbines. Spent fuel remains highly radioactive for thousands of years and must be stored in cooling pools, then dry casks.
Reactor Types and Operations
Most of the world’s 440 operational reactors are light-water designs — pressurised water reactors (PWRs) or boiling water reactors (BWRs). PWRs, like those at the UAE’s Barakah plant, circulate water under high pressure through the reactor core to prevent boiling, transferring heat to a secondary loop that drives turbines. BWRs boil water directly in the core, producing steam that spins turbines without an intermediate heat exchanger.
A typical 1,000-megawatt reactor requires 25-30 tonnes of enriched uranium per year and operates continuously for 18-24 months between refuelling outages. Capacity factors — the percentage of maximum output achieved — average 85-90% for modern reactors, according to IAEA data. France derives 65% of its electricity from nuclear power; the US operates 93 reactors generating 20% of its power; China has 55 reactors online with 23 under construction.
| Country | Operational Reactors | Share of Electricity |
|---|---|---|
| United States | 93 | 20% |
| France | 56 | 65% |
| China | 55 | 5% |
| Russia | 38 | 20% |
| Japan | 33 | 7% |
Proliferation Risk and the Enrichment Gap
The same technology that enriches uranium to 3-5% for reactors can enrich it to 90% for weapons. This is why enrichment capabilities signal proliferation risk. A nation with functioning centrifuge cascades is a screwdriver turn away from a bomb — the technical barriers collapse once the infrastructure exists.
Iran’s enrichment programme illustrates the problem. Tehran maintains it seeks only civilian nuclear power, yet its stockpile of 60%-enriched uranium exceeds 120 kilograms, per IAEA reports. That quantity, if further enriched, could yield enough weapons-grade material for three nuclear devices. No civilian reactor on Earth uses 60%-enriched fuel. Research reactors require 20% at most. The gap between stated intent and observable action defines the proliferation concern.
This is why the nuclear Non-Proliferation Treaty (NPT) distinguishes between peaceful and military use. Signatories agree to IAEA inspections, allowing monitors to verify that declared nuclear material remains in civilian use. Verification relies on cameras, seals, and unannounced inspections at declared sites. When monitoring collapses — as it has at Natanz and Fordow following Israeli strikes — the international community loses sight of what Iran is doing with its uranium. The system depends on transparency. Without it, assumptions darken.
Why Nuclear Facilities Become Targets
Nuclear infrastructure is both high-value and vulnerable. A reactor struck during operation risks radioactive release; an enrichment facility bombed during cascade operation could scatter fissile material. The UAE’s Barakah plant, which generates 25% of the country’s electricity, sits within missile range of Iran. A successful strike would cripple the UAE’s grid and potentially trigger a radiological event.
“Nuclear facilities are attractive targets not because they explode like bombs, but because disabling them severs energy supply and spreads fear — a force multiplier in strategic coercion.”
— Matthew Bunn, Harvard Kennedy School
Insurance costs reflect this reality. Lloyd’s of London and other underwriters typically exclude acts of war from nuclear operator policies, leaving governments to backstop liabilities through indemnity pools. The US Price-Anderson Act caps operator liability at $15 billion per incident; similar frameworks exist in France, Japan, and South Korea. Hardening measures — reinforced containment domes, air-defence batteries, redundant cooling systems — add 15-25% to construction costs for reactors in conflict zones, according to World Nuclear Association estimates.
The strategic calculus is brutal. Nuclear facilities cannot be relocated. They are fixed targets with catastrophic downside. Attacking them signals escalation while avoiding the threshold of using a nuclear weapon. This is why Zaporizhzhia in Ukraine and Barakah in the UAE have become flashpoints — not because they are military assets, but because disabling them achieves strategic effects without crossing the nuclear threshold.
The IAEA’s Role in Verification
The International Atomic Energy Agency, established in 1957, conducts safeguards inspections to verify that civilian nuclear programmes remain civilian. Inspectors install cameras, apply seals to fuel assemblies, and analyse environmental samples for undeclared isotopes. Iran agreed to enhanced monitoring under the 2015 Joint Comprehensive Plan of Action (JCPOA), then expelled inspectors in 2021 after the US withdrew from the deal.
Verification depends on access. When inspectors lose camera feeds or are barred from enrichment halls, the IAEA issues non-compliance reports but has no enforcement power. That falls to the UN Security Council, where Russia and China hold vetoes. The result is a system that identifies violations but cannot compel correction. The IAEA’s 2026 budget totals €449 million, funding 2,500 inspections annually across 186 member states. That figure has not kept pace with the proliferation of nuclear facilities, particularly in Asia and the Middle East.
Fuel Supply Chains and Strategic Dependencies
Nuclear fuel fabrication is concentrated in a handful of firms. Framatome (France), Westinghouse (US), and TVEL (Russia) control 75% of the global market. Russia’s dominance in enrichment gives it leverage over European reactors, which historically relied on Russian fuel assemblies. Following the Ukraine invasion, the EU moved to diversify, but replacing fuel assemblies requires reactor recertification — a process that takes 18-36 months.
Spent fuel reprocessing adds another layer. France and Russia reprocess spent fuel to extract plutonium and unused uranium, reducing waste volume and extending fuel supply. The US banned commercial reprocessing in 1977 over proliferation concerns, then lifted the ban in 1981 but never resumed operations. Japan reprocesses at Rokkasho, though the facility has faced delays since 1993. Reprocessing is expensive — roughly $1,000 per kilogram versus $200 for disposal — but reduces long-term storage requirements.
Related Coverage
For current developments in nuclear Energy Security and geopolitics:
- Gulf nuclear strike opens new front in energy warfare — analysis of the Barakah attack and its implications for regional energy security.
- IAEA verification collapse at Iranian nuclear sites erodes non-proliferation enforcement — how the loss of monitoring undermines global safeguards.
- IAEA loses track of 440kg Iranian uranium after strikes sever monitoring — tracking the material unaccounted for in Iran’s programme.
- Nuclear blackmail: how Zaporizhzhia attacks weaponise infrastructure for coercion — parallels between Ukraine and Middle East nuclear targeting strategies.