HMS Queen Elizabeth,
So far the Largest Warship ever built to the Royal Navy.
Stretching more than the houses of parliament and
Standing taller than Nelson’s Column of United Kingdom.
She is so immense so that different sections of the ship have been constructed in different
shipyards all over Great Britain and transported by barge to Scotland.
Even being such a phenomenal construction,
Ever wonder why HMS Queen Elizabeth lacks Nuclear energy as the main source of power,
while its main competitors like US Navy Nimitz Class ships are fully-fledged with Nuclear Power?
Here are the reasons why?
Let’s check it out.
Once you heard of nuclear energy,
as the source of power,
what comes to anyone’s mind is the unlimited power and the range enough for years.
HMS Queen Elizabeth designers concluded not to install them as their main source of power,
although it gives a boost to the current 25 knots top speed by the nuclear-powered engine,
which generates more wind over the deck helping to take off of air crafts.
Because this technique is less effective to HMS
Queen Elizabeth’s ski-ramp launched VSTOL aircraft.
Although the nuclear energy makes the ship free from refuelling for a long period,
nuclear-powered aircraft carrier doesn’t eliminate the dependency on refuelling tankers,
as the ship’s air group start consuming thousands
of gallons of aviation fuel when it comes to active duty.
Being a fifth-generation aircraft carrier,
Queen Elizabeth’s two Rolls-Royce Marine Trent MT30 gas turbine engine and four
Wärtsilä 38 marine diesel engines gives an added advantage of a quick start and a quick shutdown
of power efficiently with the availability of less manpower which is completely impossible
in Nuclear powered Aircraft carriers like US Navy’s Nimitz class ships.
These floating airbases usually use steam-powered - catapults to launch
aircraft and when it comes to nuclear-powered warships it gets assisted with the plenty of
heat that is generated within the boilers. But the surprise is, HMS Queen Elizabeth is
equipped with Electro-Magnetic Aircraft Launched System where it doesn’t require steam at all.
On another angle, In a pressing Brexit, Britain was not expected to bear such an expense over a
battleship where expected production cost of $ 4.4 bn overran almost to a double of $7.9bn. Even with
a requirement of purchasing a minimum number of 26 F-35B fighter jets whereby one cost around $100m
this is why, when the British carriers were on the drawing board, nuclear power was looked like
an option. With the right design, although it can run a ship without refueling up to 25 years,
Land-based reactors usually produced about 1600MW But, Marine reactors are a few hundred megawatts.
These reactors have to be very small yet powerful for their size to fit in
the limited space of a ship, even on the size of an aircraft carrier. This small size means
more expensive materials have to be used that are more resistant to radiation and the neutron
interaction with fissionable material before it escapes into the shielding is much less.
So highly enriched weapons-grade uranium is often used which increase the power density
and extends the reactor lifetime but it is more expensive and it has a greater security risk.
You also can’t rely on gravity to drop the control rods into the reactor core to shut down
like a land-based one because of the pitching and rolling motion of the ship in the sea.
So the mechanical system must work flawlessly. This and extra things like the desalination of
seawater to make fresh water for the cooling system, all add cost and make it expensive
to build a nuclear-powered ship. The size of a Queens Elizabeth carriers also limits
where they can dock and maintenance can be carried out only at nuclear certified ports.
In the United Kingdom, there is only two certified; X Berth at Devonport and Faslane.
Maintenance and decommissioning at the end of their working lives also require to bring a
substantial number of nuclear specialist from the US or France at the considered expense as
they don’t have enough of them in the UK. In the US, there is a specialized area at Puget
Sound Naval Shipyard in Bremerton, Washington for the disposal of their nuclear assets and
large areas in remote locations where the reminders of the reactors can be buried.
The UK on the other hand still to complete the decommissioning of a single nuclear submarine.
Although Britain could build nuclear carriers all it’s experience is in submarines not on surface
ships. The only shipyard set up for an assembly of nuclear-powered ships is the Rosyth one which
is currently booked up with decommissioning of old nuclear submarines and building new ones.
It is also needed to bring a substantial number of nuclear specialist from the
US or France at the considered expense as they don’t have enough of them for the UK.
Even when it comes to battle tactics, the consequences of the battle damage
occurring to a nuclear-powered surface ship with collateral radiation damage is far
greater than a nuclear submarine as it usually stays partially or completely submerged in water.
Battle damaged aircraft carrier almost act as a floating Chernobyl, where it is remains floating,
by spreading radiation to the rest of the accompanying task force etc. the United States
Navy evade this question by mentioning their numerous defence sensors and defence weapon
systems but it is quite doubtful in an age of air-independent propulsion submarines and accurate
long-range ballistics anti-ship missiles. Thank for watching. If you like the
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