LNG has been billed as a gateway fuel for the cruise industry as its transitions to greener operations, but Norwegian Cruise Line has other plans.

Cruise ships have to be designed from the keel up to run on LNG, making it an expensive commitment.

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Norwegian Cruise Line is notable among the top four cruise lines in the world for not yet embracing LNG as a ‘greener’ marine fuel option for its fleet.

It’s fellow Big Four cruise lines (Carnival, Royal Caribbean and MSC Cruises) have all either commissioned or ordered cruise ships that run on LNG, citing the environmentally friendly advantages of liquified natural gas over conventional marine diesel or heavy fuel oil.

Carnival led the charge with its Excel class back in 2018 when AIDAnova became the first 100% LNG-powered cruise ship. She has since been joined by six sister ships in the Carnival, Costa, AIDA and P&O fleets.

Another three are on order for a planned total of nine, while Royal Caribbean has ordered three LNG-powered Icon class cruise ships, and MSC Cruises plans to make at least 10 of its 12 cruise ships on order LNG-fuelled. Across the cruise fleet, more than 20 cruise ships are now LNG-powered.

Norwegian Prima

It therefore raised eyebrows in 2018 when Norwegian Cruise Line first unveiled plans for its new (conventionally fuelled) Prima class cruise ships, the first of which, Norwegian Prima, was delivered earlier this year.

LNG is cleaner and easier to use in engines, requiring less maintenance time. It is a clean-burning fuel that cuts sulphur emissions up to 99% and nitrogen oxide emissions by 85%.

This cuts greenhouse emissions overall by 30%, thereby eliminating particulate matter from the ship’s exhaust. However, investing in LNG is costly because cruise ships have to be built from the keel up to run on it, retrofitting is not feasible for most vessels.

There also aren’t many fuelling facilities currently available, so getting an LNG-powered cruise ship refuelled takes planning and can only be done at bunkering ports that specialize in LNG fuel. This was one of the major drawbacks cited by Norwegian back in 2018 when it confirmed the Prima class would be conventionally fuelled.

The low availability of LNG bunkering is a concern for Norwegian.

Norwegian Cruise Line is instead looking at biodiesel and methanol as potential future fuels to lower its carbon footprint.

“Biodiesel, from a well-to-wake way to measure it, is a close to zero greenhouse gas,” Harry Sommer, President of Norwegian Cruise Line, recently told Cruise Industry News.

“It’s compatible with the tanks and engines we have onboard. We’re going to test that and hope for the best,” he said.

Sommer added the company is working on methanol as well and thinks that the supply of green methanol will start to grow considerably in the next few years. It recently signed a deal with MAN Energy Solutions to develop methanol-powered solutions.

“We’re looking to do some tests on one of our ships and perhaps convert a fuel tank and engine to be methanol-ready so we can burn methanol fuel in port in the next couple of years,” he said.

“We’re also looking at future ships, whether it is in this series or the next series, to have methanol tanks from day one,” he added. Sommer said Norwegian would like to transition to hydrogen, but the supply chain is not in yet in place.

In the near-term, Sommer said the fleet is burning low-sulphur fuel, is equipped with exhaust gas cleaning systems and uses shore side power when available and feasible.