Introducing the world’s largest cruise ship

The latest addition to Royal Caribbean’s award-winning fleet sailed into Southampton recently, and it’s a monster both in terms of size and consumption.

First, the dimensions. The Harmony of the Seas is 1,188ft long (taller than the Eiffel Tower if stood up on its end) and 215.5ft wide. With 18 decks (16 for passengers, two for crew) it sits 230ft high), weighs 227,000 tons and can carry a total of 6,780 guests, plus 2,100 crew. It has 23 swimming pools (including the deepest one at sea), 20 restaurants serving everything from burgers to sushi, a ten-storey water slide and even 52 trees in its own park!

There are seven ‘neighbourhoods’ which offer a huge range of distractions and entertainments; from cocktail-making robots in the Bionic Bar and enjoying café society on the Boardwalk, to strolling through Central Park and braving the 100-foot drop of that ten-storey water slide. There’s also a casino, 1,400-seat musical theatre (beginning with Grease), live jazz club, cinema, karaoke bar, video games arcade and comedy club.

Less a floating hotel, more of a floating city, the Harmony of the Seas took three years to build at an estimated cost of £700m ($1 billion) at the Saint-Nazaire docks in France. She’ll begin her official maiden voyage to the Mediterranean on 29 May. From there she’ll run cruises from Barcelona and Rome, before crossing the Atlantic to offer Caribbean cruises from the US this winter.

Not surprisingly, keeping a town afloat requires a lot of power. Propulsion is provided by three four-storey 18,860kW Wärtsilä 16V46 16-cylinder main generator diesel engines and three similar Wärtsilä 12V46 12-cylinder engines, each producing 13,860kW apiece to maintain a cruising speed of 22 knots.

The propulsion power comes from three ABB Azipod electric azimuth thrusters, and manoeuvring is helped by four 5,500kW Wärtsilä CT 3500 tunnel thrusters in the bow, each delivering 7,500 horsepower. Electricity is supplied by two MTU 16V4000 emergency generator diesel engines.

That’s an awful lot of power, and it requires an awful lot of fuel. Each of the 16-cylinder engines at full power can burn 1,147 gallons of diesel fuel an hour, or nearly 80,000 gallons a day, and there’s already been criticism of the pollution generated by such a high usage of diesel fuel that simply wouldn’t be tolerated on land.

It’s possible that the conspicuous consumption of the world’s largest cruise ship will draw attention to this anomaly, and eventually lead to the same sort of pollution standards that we benefit from on land, but for the ship’s passengers (and its investors), big clearly equals beautiful.

Image courtesy of Royal Caribbean International


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