How Nuclear-Powered Submarines Work


How Nuclear-Powered Submarines Work

Under a historic new deal with the US and UK (which practically ditched France), Australia is set to build a new fleet of nuclear-powered submarines. Let’s see how these submarines work and their pros and cons.

Crux of the Matter

Is This Submarine A Nuclear Weapon?
No! Their outer surface is like any other submarine, with the difference lying in the manner it is powered. In fact Australia is following the Treaty on the Non-Proliferation of Nuclear Weapons, which basically means Australia cannot make a nuclear weapon.

So How Will It Work?
In a nuclear-powered submarine, reactors are fuelled with Uranium. Uranium-235 is bombarded with neutrons inside the reactor, causing some of the nuclei to undergo nuclear fission. 

Then a nuclear chain reaction occurs and more neutrons are released. The energy is released as heat, which is used to drive turbines generating electricity for the submarine.

What Are The Pros Of Going Nuclear?

  • Long refuelling gap - on entering service, a single submarine reportedly has Uranium fuel to last 30+ years. With such long gaps, they can can stay submerged at deep levels for longer time.

  • They operate at high speed for longer periods than conventional submarines.

What About The Cons?
Such submarines are costly to build and require highly skilled workforce. While Australia has a sufficient supply of Uranium, it lacks the capacity to enrich or fabricate the reactor fuel.

What Is AUKUS?
AUKUS is a new trilateral partnership among the US, Australia and the UK. It will also cover tech like AI, in order to counter China. Australian PM Scott Morrison has stated that the nuclear submarine fleet will be launched by 2040. 

Why Is France Unhappy With The Deal?
France will lose $65 billion from an existing deal with Australia. Under the deal, France would have provided the latter with diesel-powered submarines.

What About India?
Currently India has 15 conventional submarines in operation. Also, the Indian Navy has the indigenously built INS Arihant, and soon to be commissioned, INS Arighat.


First tested in 1800, Nautilus is considered to be the first practical modern submarine. It was designed by American inventor Robert Fulton for the French Government.

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