Compare

Putting similar-but-different things side by side is one of the fastest ways to understand them. Here are the comparisons that matter most.

PWR vs. BWR

The two light-water reactors that make up most of the world's fleet.

  Pressurized Water (PWR)Boiling Water (BWR)
Water in the core Stays liquid under high pressureBoils directly into steam
Steam to turbine Separate, clean secondary loopCore steam drives turbine directly
Turbine loop Non-radioactiveMildly radioactive
Pressure Higher (~155 bar)Lower
Share of fleet ~2/3 of reactorsMost of the rest

Takeaway: Both are proven and safe; the PWR's extra loop keeps the turbine side clean at the cost of higher pressure.

LNT vs. Hormesis

The genuinely unsettled question at the heart of radiation fear.

  LNT (regulatory model)Hormesis (challenger)
Claim Any dose carries proportional riskLow doses are harmless or protective
Threshold No safe thresholdEffective threshold exists
Used by Regulators worldwideA minority of researchers
Evidence at low dose Hard to measure — extrapolatedHard to measure — debated
Status Mainstream defaultNot adopted by regulators

Takeaway: This is labelled CONTESTED for good reason — both strong positions go beyond what the data firmly establish.

Nuclear vs. Gas vs. Solar

How three clean-ish sources stack up at the system level.

  NuclearNatural gasSolar
Dispatchable? Yes (firm)Yes (firm)No (variable)
Lifecycle CO₂ Very lowHighLow
Capacity factor ~90%+Flexible~15–25%
Land use Very smallSmallLarge
Build cost High up-frontLowLow per panel
Needs backup/storage NoNoYes

Takeaway: Nuclear is firm and clean but capital-heavy; solar is cheap but variable; a clean grid likely wants the firm backbone nuclear provides.

SMR vs. Large Reactor

Two bets on how to build nuclear affordably.

  Small Modular (SMR)Large (Gen III, e.g. AP1000)
Output Under ~300 MWe~1,000+ MWe
Built In a factory, shipped to siteOn-site, piece by piece
Cost strategy Economies of series productionEconomies of scale
Up-front capital Lower per unitVery high
Proven? Not yet at scaleYes (Vogtle 3 & 4)

Takeaway: Large reactors are proven but capital-intensive; SMRs are a promising but still-unproven bet on factory production.