Photo courtesy of Carnival Cruise Line

The cruise industry is ever-evolving and growing, and today, Carnival Corporation has announced plans for three new ships – its two largest for the Carnival Cruise Line brand and one more for P&O Cruises – all of which will be powered exclusively by clean-burning Liquefied Natural Gas (LNG).

As for size, the new pair of 180,000-ton Carnival ships will exceed the 164,600-ton Norwegian Escape, the current biggest from Norwegian Cruise Line, and approach Royal Caribbean International’s 226,963-ton Harmony of the Seas, the largest cruise ship in the world. Despite falling short of the 5,479-passenger Harmony by over 45,000 tons, the new Carnival ships will come closer to its capacity with 5,200 guests onboard.

If that’s starting to sound cramped, it probably shouldn’t.

Carnival Corp. previously revealed plans to build four even larger ships over 180,000 tons each for its AIDA Cruises and Costa Cruises brands that will carry a staggering 6,600 passengers. At that time, Carnival said, “A major part of the innovative design involves making much more efficient use of the ship’s spaces, creating an enhanced onboard experience for guests.”

Part of the efficiency in space might be coming in part thanks to the new power-plants. LNG signifies Carnival Corp.’s “green cruising” initiative by powering 100 percent of the ships’ energy needs at sea and in port. Currently, the company’s new AIDAprima for the German AIDA Cruises brand is the first cruise ship to be powered by LNG as built at Mitsubishi Shipbuilding in Japan.

Carnival Cruise Line’s yard shift from Fincantieri in Italy to Meyer Turku in Finland is likely prompted by the LNG technology as Meyer Werft and Meyer Turku will be building five other future vessels using the new fuel source for AIDA Cruises, Costa Cruises, and P&O Cruises as well.

Also pursuing LNG power is MSC Cruises for its World-class ships to be built at STX France in Saint-Nazaire for launches beginning in 2022. Meanwhile, the Carnival ships are set to come online in 2020 and 2022.

The push to go both larger and cleaner parallels endeavors for greater efficiency and higher profits. Larger ships follow an economy of scale wherein a single ship with a larger capacity is more effective than several smaller ships carrying fewer passengers. LNG fuel prices are stable now, so the investment in the technology is prudent. However, in the past, gas turbine power for cruise ships was also clean but eventually cost-prohibitive, requiring a greater return to diesel fuel over time. The long-term economic efficiency of LNG is still to be determined.

Looking to the future, there is seemingly no end in sight for bigger cruise ships across the board. The only thing ever holding back their increase is the size of the shipyards as well as the international ports that can accept them.

Provided both continue to scale up, cruise ships are likely to get larger still.