Princess Cruises has marked the start of construction of its new Sphere-class cruise ships, with the first steel cut at Fincantieri in Italy.

The 175,000-gross ton, LNG-powered Sphere-class cruise ships will be the largest ever built in Italy, and the first LNG vessels to be operated by Princess Cruises.

Princess Cruises has not released a rendering of the new class of ships, but they are likely to be similar to the LNG-powered Excellence class.

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The first steel sheets for the ships were cut at San Giorgio di Nogaro (Udine) in Italy, at Centro Servizi Navali, a company specialized in logistics and production of sheet metal for the Fincantieri shipyards.

The steel sheets will then be used to assemble the construction blocks for the ships at Fincantieri’s Monfalcone yard. Each block will then be welded together to form the hull and superstructure of the giant vessels.

Princess Cruises has signed an initial order for two Sphere-class ships, which will be largely identical to each other, with both carrying 4,300 guests based on a next-generation platform design.

Princess and Fincantieri executives mark the first steel cutting for the new Sphere class.

The vessels will be dual-fuel powered, meaning they will be designed to run on both diesel and LNG, although Liquefied Natural Gas, a much greener marine fuel which emits far fewer emissions than traditional fuels, will be the primary power source.

The ships will be the 16th and 17th ships in the Princess fleet, which currently numbers 14 ships, with a new Royal-class vessels, Discovery Princess, due for delivery in January, 2022.

The two unnamed Sphere-class cruise ships will be delivered in November, 2023 and May, 2025, with onboard features and amenities and upcoming itineraries to be announced later this year.

P&O Cruises’ Iona of the Excellence class

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Although these will be the first LNG-powered cruise ships for Princess, they are the latest in a new range of massive LNG cruise ships being built for various brands owned by Carnival Corporation.

AIDA Cruises, Costa Cruises, P&O Cruises and Carnival Cruise Line have all taken delivery of Excellence-class cruise ships (AIDAnova, Costa Smeralda, Iona and Mardi Gras), with five more under construction.

AIDA is due to take delivery of AIDAcosma this year (her delivery was delayed due to the COVID-19 pandemic), Costa will take delivery of Costa Toscana in December, 2021, and Carnival and P&O will take delivery of Carnival Celebration and Arvia next year.

AIDAcosma was initially scheduled to homeport in Dubai for the coming 2021/22 cruise season, but has since been replaced with her sister ship AIDAnova.

A third Excellence-class cruise ship is also on order for Carnival Cruise Line and will be delivered in 2023.

At 180,000-gross tons, the Excellence-class cruise ships are slightly larger than Princess’ Sphere-class, all of them have been built at Meyer Werft’s shipyards in Germany and Finland.