Alternative Fuels
We are working with suppliers to encourage investment
in a reliable supply infrastructure. Our ship engines can be adapted for sustainable alternative fuels such as biofuels, green methanol and synthetic fuels. We are working with classification societies and other stakeholders to assess lower GHG emission fuel options for cruise ships. However, cleaner renewable fuels are not available or used in large quantities.
LNG is currently the best readily available fuel to help reduce GHG emissions.
While LNG is a fossil fuel that generates GHG, it can be produced as a low carbon fuel as biomethane and ultimately e-methane.
Biofuels offer environmental benefits compared to using fossil fuels alone through their lifecycle CO2 reductions.
These biofuels can be used in existing ship engines without modifications to the engine or fuel infrastructure however, supply is limited, and biofuels are more expensive than their fossil fuel counterparts.
To provide a path to net zero emissions, alternative low GHG emission fuels will be necessary for the maritime industry. We are working with suppliers to encourage investment in a reliable supply infrastructure.
Liquefied Natural Gas (LNG)
LNG is currently the best readily available fuel to help reduce GHG emissions. The ships built to use LNG can also use bio or synthetic forms of the energy source in the future. We have nine LNG powered cruise ships in operation as of January 1, 2024, and four that are expected to join the fleet through 2028. All our LNG ships also have the capability to run on MGO.
LNG is a fossil fuel and generates GHG emissions – however, it is also a fuel in transition as it can be produced as a low carbon fuel as biomethane and ultimately e-methane. LNG’s direct CO2 emissions are lower than those of conventional fuels and it emits effectively zero sulfur oxides (only the sulfur in the pilot fuel is present), reducing nitrogen oxides by 85% and particulate matter by 95%-100%. Both on a tank to-wake and well-to-wake basis when measured using the scientifically accepted 100-year GWP, LNG has lower overall GHG emissions than conventional fuels.
The types of engines that we use are subject to small amounts of methane slip (the passage of un-combusted methane through the engine). There are different views relating to the measurement of the environmental impact of LNG, including the methane slip. Our disclosures report our emissions, including methane slip, as part of our total GHG emissions (reported as CO2e) using the 100-year global warming potential (“GWP”) time frame and measured on a tank-to-wake basis.
We are working closely with our engine manufacturers and other technology providers to further mitigate methane slip and we are part of the Methane Abatement in Maritime Innovation Initiative, where we are partnering with other major maritime players to seek solutions for this challenge. We are also evaluating options to remove unburnt methane from exhaust streams. Our nine LNG ships in service represent 17% of our fleet capacity.
Biofuels
During 2023, we piloted the use of biofuel as a replacement for fossil fuel on a third ship (after two successful trials in 2022).
After AIDAprima became the first large-scale cruise ship to be powered with a blend of marine biofuel, made from 100% sustainable raw materials, and marine gasoil (“MGO”), Holland America Line completed two pilots on Volendam, one using a blend of marine biofuel and another using 100% biofuel, becoming the first large-scale cruise ship to be powered 100% by biofuel.
In 2023, Carnival Magic completed a similar trial as Volendam, using 100% biofuel.
The certified biofuels used in these pilots offer environmental benefits compared to using fossil fuels alone through their lifecycle CO2 reductions. These biofuels can be used in existing ship engines without modifications to the engine or fuel infrastructure, including on ships already in service.
We are working with companies making biofuels however, supply is limited, and biofuels are more expensive than their fossil fuel counterparts. We have tested various feedstocks, and we are pleased with the results. We intend to test other feed stocks over the next few years.
New Technologies and Alternative Fuels
While fossil fuels are currently the only scalable and commercially viable option for our industry, we are closely monitoring technology developments and pioneering important sustainability initiatives in the cruise industry.
We have partnered with companies, universities, research bodies, nongovernmental organizations, and other key organizations to help identify and scale new technologies not yet ready for the cruise industry. For example, we have piloted maritime scale battery technology, a fuel cell and biofuels.
We anticipate that fuel cell and battery storage systems may help supplement some of the main energy supply needed to run our ships and that biofuels, if available to our sector at scale, will also contribute to our pathway. However, these alone will not be sufficient to help us achieve our ultimate aspiration.
To provide a path to net zero emissions, alternative low GHG emission fuels will be necessary for the maritime industry; however, there are significant supply challenges that must be resolved before viability is reached. We are working with suppliers to encourage investment in a reliable supply infrastructure.
Our ship engines can be adapted for sustainable alternative fuels such as biofuels, green methanol and synthetic fuels. We are working with classification societies and other stakeholders to assess lower GHG emission fuel options for cruise ships. However, cleaner renewable fuels are not available or used in large quantities.
LNG Program Timeline
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At Carnival Corporation & plc, our purpose is to deliver unforgettable happiness to our guests by providing extraordinary cruise vacations, while honoring the integrity of every ocean we sail, place we visit and life we touch.