Carbon cropping

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Before Royal Caribbean announced its 2020 target of reducing greenhouse gas emissions by 35 percent as part of a five-year partnership with World Wildlife Fund (WWF), it had to do something never before done in the cruise industry.

While other transportation sectors – planes, trains, automobiles – could adopt the recently available decarbonization approaches of the Science Based Target initiative, a specific pathway for the cruise industry simply didn’t exist. WWF recommended the target be science-based, and RCL worked with Ecofys to devise an approach that aligned with climate science and addressed the specific characteristics of the cruise industry.

“They were part of the sector ‘other transport,’” says Esther Eggink of Ecofys, a global energy and climate consultancy. “They were in a big basket with other transport companies and activities that are not per se related to the cruise industry. Now we’ve made a specific approach for the cruise industry that really fits them.”

Because of carbon goals it adopted in 2010, RCL was already dedicating significant resources and making encouraging progress on cutting emissions.

In setting an even more ambitious decarbonization goal for 2020, “we did change the metric that we’re measuring ourselves against a little bit,” explains Nick Rose, RCL’s environmental regulatory lead.

Instead of calculating carbon emissions according to the passengers carried and number of days sailed on a cruise, they’re now measured by the number of passengers carried and distance traveled. “It’s lining us up with how the world is going to have us capture as well as publish what our numbers are,” Rose says.

One of the main contributors by far to RCL’s carbon footprint is propulsion.

“It’s about 60 percent of the energy that we consume, therefore it’s arguably 60 percent of the carbon we emit,” Rose says. “In order to drive that down we’re looking at ways in which we can reduce our propulsion needs.”

Among them are the coatings and configuration of ships’ hulls, as well as propeller design.

Already in use is an integrated electronic system driven by industry-first software that calculates the best operational choices – trim, speed and route – for the most efficient use of fuel.

Some of the carbon-killing goal is built in as new, more efficient vessels join the fleet while older tonnage leaves, such as the Project Icon-class which will be the cruise company’s first foray into liquid natural gas (LNG). In other cases, when it makes economic sense, older ships are and will be retrofitted with technologies from the new ships. Among them, air lubrication using a blanket of bubbles to decrease friction between the hull and the water. Depending on the ship, Rose says, it offers a net fuel savings of two to four percent.

Other areas to be tested or already in use for carbon reduction:

  • Using seawater in cold climes to supplement chemical coolants in ships’ HVAC systems, which are the second biggest energy consumers.
  • Assuring that when refrigerants are used in ships’ chillers, they’re both efficient and contribute minimally to global warming. “We try to manage that so we’re getting the best of both worlds where possible,” Rose says.
  • Replacing hot incandescent bulbs with cool LED in systems that automatically dim lights in public spaces and staterooms when no motion is detected.
  • Keeping pace with the most efficient equipment for preparing and storing food in ships’ galleys.

The search for carbon savings is constant and ongoing and manages to serve two masters, both the environment in which RCL makes its living and the bottom line earned by doing so.