Number of firm LNG cruise newbuilds climbs to 19Number of firm LNG cruise newbuilds climbs to 19

Nine in Carnival Corp. & plc group

Besides the TUI pair, they include nine newbuilds in the Carnival Corp. & plc group (three for AIDA Cruises, and two each for Costa Cruises, P&O Cruises and Carnival Cruise Line).

Plus MSC, Disney, Royal Caribbean

MSC Cruises' fifth Meraviglia-class ship will use LNG, along with its two World Class newbuilds, as will Disney Cruise Line's trio of new ships and Royal Caribbean International's two Icon-class vessels.

Of these, the first in service will be AIDAnova, scheduled for delivery in November.

Options for further newbuilds—for example, MSC has options for two additional World Class ships—are likely to increase the number of LNG vessels within this group of owners.

And who knows which other operators may opt for LNG?