Nuclear SMR - Reactor-to-Shaft Equivalent

Small Modular Reactor propulsion is zero-carbon at operation. WtW GHG comes entirely from reactor construction, fuel cycle, and decommissioning. This tool compares reactor energy output to conventional fuel equivalence.

FuelNuclear

Reactor thermal powerMW_thThermal → shaft efficiencyTypical marine SMR (high-temperature gas or molten-salt) achieves 30–45 % thermal-to-shaft.Annual operating hourshLifecycle GHG intensitygCO₂e/MJNuclear lifecycle intensity is ~0.5 gCO₂e/MJ for thermal energy. For shaft energy (after efficiency), scale accordingly.

Annual shaft energy: 1,296,000GJ

Equivalent VLSFO mass avoided: 71,111t

Assuming 40.5 MJ/kg VLSFO and 45 % engine efficiency (same as reactor)

Lifecycle GHG: 648.0t CO₂e

Changing the inputs requires JavaScript. The calculator above shows its default inputs and result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, limits

\text{TTW CO}_2 \text{ (t)} = \text{mass} \cdot C_f

\text{Energy (MJ)} = \text{mass (kg)} \cdot \text{LCV (MJ/kg)}

\text{WtW (t CO}_2 \text{e)} = \frac{\text{Energy (MJ)} \cdot \text{WtW factor (g/MJ)}}{10^6}

WtW factors include upstream extraction, processing, transport, plus tank-to-wake combustion and relevant CH₄/N₂O. FuelEU Maritime Annex II publishes the authoritative defaults.

In short

Compare nuclear Small Modular Reactor propulsion to conventional fuel equivalence - shaft energy, fuel displacement, lifecycle GHG.

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