Hurtigruten’s Roald Amundsen is the world’s first hybrid-electric cruise ship.

FORT LAUDERDALE — Cruise lines are cutting carbon emissions, reducing single-use plastics and campaigning to restore endangered coral reefs around the world, an audience at Cruise World learned on Friday.

Two cruise lines with different solutions to environmental preservation led to a discussion of how they’re making progress.

Hurtigruten’s unique solution comes in the form of batteries, which on its newest ships store energy produced by the engines and cut greenhouse gas emissions by up to 20%.

Hurtigruten president of the Americas John Downey said the 630-passenger ships can sail for several hours at slow speeds by battery power alone, and for a little less than an hour at normal cruising speed.

That could be important as soon as 2026 when Norway has mandated that ships sailing in two of its most historic fjords be 100% emission-free. Few ships in the current cruise fleet could qualify, Downey said.

“We can do it today. If we go 100% batteries, we can sail in there emissions-free,” Downey said.

At MSC Cruises, executives just announced that it will become the first large cruise line to become carbon neutral by countering its engine emissions through purchased carbon offsets. By investing in companies that plant trees and purchase wetlands, the line will absorb carbon dioxide in the atmosphere equal to the greenhouse gasses it produces.

“This is super exciting for us,” said Bonnie Levengood, MSC Cruises USA’s senior vice president for marketing. “As we’re investing in new technology to be more eco-friendly, we’re also looking at what is our current carbon footprint and how can we reduce that now.”

MSC is also developing a coral education and restoration program on the new MSC Ocean Cay Marine Reserve, its private island near Bimini scheduled to open Dec. 5.

The line is working with universities and researchers to develop a strain of super coral that will be more resistant to coral bleaching, a byproduct of warmer water temperatures. If the research is fruitful, it could help not only the Bahamas but other areas with coral reefs.

“Coral is a big attraction for tourists all over the world,” Levengood said.

Both companies are reducing sulfur emissions from their exhaust as required by International Maritime Organization rules that have been phased in over the past decade, but they differ on methodology.

Hurtigruten switched to low-sulfur fuel 10 years ago for its fleet of small ships, which prevents the sulfur from getting into the exhaust, while MSC mainly uses exhaust stack “scrubbers” that use seawater to capture the sulfur before it leaves the funnel.

Downey said the captured sulfur must still be disposed of somehow. “Our approach is you start at the root cause instead of band-aiding,” he said, adding that MSC prefers scrubbers because low-sulfur fuel is expensive.

Levengood responded that every environmental technology has its positives and negatives. She pointed out, for example, that Hurtigurten’s batteries use metals that have to be mined, and that the mining process produces greenhouse gases, even if the end product may not.