key points and developing reactor plant options

Maritime Nuclear Power

John S Ross

March 2021

Introduction

● Pertinent facts

● Key structural changes

● LR does not promote one power technology over another

Adoption of nuclear power – in 15 minutes…….

Nuclear Propulsion

USS Nautilus 1955

Since then the applications to merchant ships have included:

➢ NS Lenin

➢ NS Savannah

➢ NS Otto Hahn

➢ NS Mitsui

➢ Russian ice breaker classes

➢ NS Sevmorpot

➢ NS 50 Let Povbedy

NS 50 Let Povbedy

N.S Otto Hahn

N.S. Savannah

~700 reactors have served at sea.

~100 reactors today

U.S.S Nautilus

Nuclear power emissions & power density

• Zero emissions from nuclear propulsion

➢No CO2, NOx, SOx, Particulates

• Only proven fuel capable today of fossil fuel replacement in all marine applications

Relative power densitiesUranium is ~ 40,000,000Thorium is ~ 23,000,000more power dense

Fuel Energy Density (MJ/L)

Uranium 1,539,842,000

Thorium 929,214,000

Hydrogen (liquid) 10.004

LNG 22.2

Crude oil 37

Diesel fuel 38.6

Ammonia (liquid) 11.5

Nuclear technology

Uranium ‘typical’ fuel used today (water based reactors)

➢ 500 times more abundant than gold & common as tin

➢ Found everywhere, rock, soil, sea. Granite (60% of earths crust) 4ppm

➢ Natural uranium is made up from U238 0.7% U235

Thorium – 6ppm (molten salt reactors)

Nuclear reactor – heat source

➢ Steam cycle - boiler replacement

Space – not dissimilar to a diesel plant

Small Modular Reactors 10 – 300MWe

Design, build, operation & decommissioningDesign

➢Radiation additional hazard

➢Shielding from radiation

➢Collison protection – location

➢High integrity systems

➢Vibration tolerance

➢Accelerations

➢Whole life cycle

➢Systems engineering

Build

➢High integrity

➢Additional facilities

➢System commissioning

Operation

➢Safety Culture

❖Employment regime

❖Training regime

❖Health physics

➢Manning levels

➢Terrorist threat

➢Public perception

➢Ports & local population

➢Dry dock & refuelling

➢Maintenance

➢Emergency response

➢Waste management

DecommissioningWaste disposal

Business process ● Prove new technology

– Life cycle

● Establishing build / refuelling facilities

● CAPEX vs OPEX vs total life costs

● Insurance / P&I

– Discussions in 2010 suggest existing solution

● Paying for fuel

– Charterer typically pays for the fuel

– Reactor fuelled for many years

• Pressurised Water Reactor 3-5 yrs

• Thorium Molten Salt Reactor 20+ yrs

● Nuclear decommissioning & waste storage cost included

● Fossil fuels waste disposal cost not included

– poured into the atmosphere

Thorium Molten Salt vs Water Based, Solid Fuel Reactors

Lloyd's Register 8

Water based, solid fuel – power stations

• Water used to move energy ~ 100 Bar

• If loss of pressure & failure of redundant systems – fuel uncovered, fuel plate damage

• Solid fuel – needs to be refuelled every 3-5 years.

• Removed fuel > re-processed to use significant amounts of unused fuel.

• Vast global experience

• Exemplary safety record, by any measure.

• Active safety measures

• 4th Generation & SMR’s passive safety features

Thorium Molten Salt

• Molten salt used for energy transfer ~ 1 bar

• Loss of circuit pressure > molten salt does not flash of > fuel is in the molten state so cannot be uncovered with loss of heat sink

• Fuel is molten – allows full energy extraction ~ 20yrs refuelling

• 1960’s best option for power production

• Protype plant 1960’s – not taken forward

• Development & testing being undertaken

• Inherent passive safety features

Regulatory Aspects

Lloyd's Register 10

• SOLAS Chap VIII > IMO Resolution A.491(XII)

• UNCLOS III – ratified in 1994

➢Internal waters; Territorial waters (12 miles);Contiguous zone

➢Exclusive economic zones (200 mile); Continental shelf

• Allows for the free movement of vessels from one country to another

• Land based nuclear plant need national ’approval’

• Improbable that a nuclear powered ship would be allowed to sail into another countries waters / ports.

➢More needs to be done in this area

➢Principal challenge for nuclear propulsion

Conclusions

Lloyd's Register 11

• Vast experience of operating maritime nuclear plant

• No country to county trade with merchant marine nuclear power today

• Challenges for the civil marine industry

• Vast technical & operational experience

• Some aspects of marine business need to change

• Complete replacement for fossil fuel

• Risks real & perceived

• Hurdle – regulation allowing a reactor to move freely from country to country.

• Floating Nuclear Power Plant may be a first step

Lloyd's Register 12

Thank you

Please contact:

John Ross,

Global Risk Coordinator

Tel +44 (0) 3304 140449

Mob +44 (0) 7580 716 022

John.S.Ross@lr.org