World’s largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Fuel Consumption Soars With Ship Size
The debut of Royal Caribbean's Wonder of the Seas in March 2022 marked a new era in cruise ship engineering. At 236,857 gross tons and able to accommodate 6,988 guests, Wonder of the Seas is the largest cruise ship ever built. Its towering size symbolizes the cruise industry’s relentless pursuit of economies of scale. However, many sustainability advocates argue bigger is not always better when it comes to cruise ships.
According to maritime data provider RightShip, a mid-sized cruise ship burns roughly 150 to 200 tons of fuel per day. As cruise ships get bigger, fuel consumption increases exponentially due to greater power requirements. For example, Royal Caribbean's Symphony of the Seas burns through around 1,500 tons of heavy fuel oil (HFO) each day.
HFO is the cheapest, bottom-of-the-barrel refined product that comes from crude oil. It contains 3,500 times more sulfur than automotive diesel and its high viscosity requires it to be heated before use. When burned in massive onboard engines, HFO releases nitrogen oxides, sulfur oxides and particulate matter that contribute to air pollution and acid rain.
Large cruise ships not only burn more fuel per day, they also operate more days per year than smaller vessels. Industry experts estimate Oasis-class ships from Royal Caribbean operate around 330 days annually. Assuming a daily consumption of 1,200 - 1,500 tons of HFO, Royal Caribbean’s largest ships could be burning 400,000 to 500,000 tons of high-sulfur fuel per year.
What else is in this post?
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Fuel Consumption Soars With Ship Size
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Waste Management a Growing Challenge
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Air Pollution Worries Port Cities
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Heavy Reliance on Dirty Fuels
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Cutting Emissions With New Technology
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Sustainability Efforts Divide Cruise Lines
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Balancing Tourism Jobs and Environment
- World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Regulating The Cruise Industry's Footprint
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Waste Management a Growing Challenge
With thousands of passengers and crew onboard, waste management becomes an immense undertaking on mega cruise ships like Royal Caribbean's Oasis and Quantum class vessels. Food waste, sewage, greywater, packaging materials, hazardous wastes and solid refuse must all be handled and disposed of responsibly.
However, limited space for storage and processing makes waste management a constant logistical juggle. Cruise ships utilize incinerators to burn waste, but these release particulate matter, sulfur oxides and nitrogen oxides into the air. Sewage and greywater can be treated through marine sanitation devices but discharges may still contain untreated human waste, cleaning agents, microplastics and more. While some waste can be landed for recycling or disposal, a cruise ship far out at sea has few options but to dump waste overboard.
According to Klein, a typical one week cruise produces over eight tons of solid waste. With larger ships carrying up to 7000 passengers, this number inflates dramatically. Sirince says a mega cruise ship can generate up to 210,000 gallons of sewage and 1 million gallons of greywater each week. About 25% of greywater is untreated before dumping.
Food waste is a major component, with thousands of meals served daily. Cruise lines are getting better at waste reduction by improving menu planning and inventory controls. But unavoidable food waste still totals around 7 pounds per person per day. Much is ground up and dumped with only around 7% landed for composting.
Packaging is another huge waste contributor. Massive amounts of plastics, cardboard, metals and glass stem from provisioning a small city on the sea. While some lines are improving recycling rates, storage space limits mean most waste must be incinerated or dumped overboard.
Hazardous wastes like used oils, batteries, paints, lightbulbs, cleaners and medical waste also accumulate quickly with thousands of passengers and crew. Limited storage space and safety concerns constrain how much can be landed for proper disposal. So some hazardous wastes inevitably get dumped or burned at sea.
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Air Pollution Worries Port Cities
When a mega cruise ship like Royal Caribbean’s Wonder of the Seas pulls into port, it brings more than just thousands of tourists. It also delivers a blast of harmful air pollution.
Cruise ships burn massive quantities of heavy fuel oil while at sea. But many continue using dirty fuels while docked to keep the lights on and climate control running. Others may switch to slightly cleaner yet still highly polluting marine gas oil.
These fossil fuels contain sulfur oxides, nitrogen oxides and particulate matter that contribute to smog and acid rain in port cities. According to 2019 research by the non-profit Stand.Earth, cruise ships emit 10 times more sulfur oxide around European ports than all 260+ million European cars combined.
Cruise hubs like Barcelona, Venice and Dubrovnik now suffer from black carbon pollution levels that rival heavily industrialized cities in China. Measurable spikes in pollution directly correlate with cruise ships docking, idling their engines to run onboard systems.
Yet port cities have little power to curb cruise pollution. International maritime guidelines prohibit them from regulating ship fuels and emissions. Their only option is plugging ships into onshore power grids - but this is costly for cities and not many cruise berths are equipped with shore power.
So port cities are starting to fight back. In 2019, the mayor of Marseille banned the most polluting cruise ships from docking in the heart of the city. Barcelona authorities ordered cruise ships to plug into shore power or face restrictions. Italy banned large ships from entering Venice's historic city center.
The Cruise Lines International Association contends the industry has cut ship air emissions 25% since 2005. But cruise ships mainly did this by installing scrubbers to remove sulfur - not by switching to cleaner fuels. Scrubbers just dump pollutants into the ocean instead of the air.
Some lines are starting to use liquefied natural gas (LNG) instead of heavy fuel oil. But LNG provides only marginal air quality improvements and its methane leaks make it nearly as harmful to the climate as coal. Shore power helps but many ships/ports aren't equipped for it yet.
So port cities continue to suffer from repeated blasts of sooty smoke whenever cruise ships visit. Until the industry transitions to truly clean fuels and zero-emissions technologies, these communities will keep fighting for their right to breathe clean air.
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Heavy Reliance on Dirty Fuels
The cruise industry runs on fossil fuels - and not the clean, low-sulfur kind. Most large cruise ships today still burn heavy fuel oil (HFO), the literal bottom of the barrel when it comes to petroleum products. This tar-like sludge is thick, dirty and cheap - exactly what cruise lines want to power their floating cities.
HFO contains up to 3,500 times more sulfur than highway diesel. When burned in massive ship engines, it spews out sulfur oxide, nitrogen oxide and particulate emissions that contribute to acid rain, smog, respiratory illness and climate change. Just one cruise ship can emit as much particulate pollution as a million cars in a single day. Yet these ships are still allowed to burn HFO freely on the high seas.
Some cruise lines have installed exhaust scrubbers to remove sulfur emissions before the smokestacks belch their filth into port cities. But scrubbers just dump the pollution into the ocean instead of the air. And they do nothing to eliminate nitrogen oxides, particulate matter and black carbon. These pollutants continue to choke port communities whenever cruise ships visit.
A few small ships run on cleaner liquefied natural gas, but this marginal improvement comes with massive infrastructure costs. And LNG still emits methane, an extremely potent greenhouse gas. What's really needed is an industry-wide switch to zero emissions battery or hydrogen fuel cell power. But that technological leap requires massive investments that no cruise line is yet willing to make.
In the meantime, communities suffer from the industry's addiction to heavy fuel oil. When cruise ships dock in port cities like Dubrovnik and Barcelona, pollution levels spike to nearly double the background rate. Citizens inhale massive gulps of harmful sulfur and nitrogen oxides that wouldn't even be legal for trucks to emit ashore.
Cruise industry reps claim they've cut ship emissions 25% since 2005. But the rapid growth in fleet size nullifies these efficiency gains. Royal Caribbean's Oasis-class ships each burn over 1,500 tons of HFO per day - more than 10 times what a medium-sized cruise ship consumes. New mega ships coming online means total particulate emissions will keep increasing even as emission rates per ship drop.
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Cutting Emissions With New Technology
While the cruise industry currently relies heavily on dirty fossil fuels, innovative companies are developing new technologies to help ships cut emissions. Transitioning to alternative power sources like fuel cells, batteries and hybrid systems could drastically reduce the industry's carbon footprint. But it requires massive investments that companies are only starting to make.
The nonprofit Bellona Foundation deployed the first cruise ferry powered by hydrogen fuel cells in 2021. The MS Green Åland can carry 360 passengers on day trips with zero emissions besides water vapor. Fuel cells combine hydrogen and oxygen to generate electricity through a chemical reaction. The only byproduct is water, eliminating pollutants.
But expanding hydrogen infrastructure is cost prohibitive, from producing green hydrogen to distributing and storing it. Right now, most hydrogen is extracted from natural gas in a process that releases carbon dioxide. Bellona envisions ships eventually running on green hydrogen produced via electrolysis powered by renewable energy.
Several other companies are developing hydrogen fuel cell river cruisers. These short, predictable routes are ideal testbeds for scaling up the technology before tackling massive ocean liners. But fuel cells currently remain far too energy intensive and expensive for mainstream adoption.
Another zero emission option is large battery banks. The first all-electric cruise ferry is under construction for launch in 2022. It will carry 600 passengers and 120 cars on short crossings. But most hybrid ferries still use diesel generators to extend range, as batteries can only provide a few hours of propulsion.
For oceangoing cruise ships, even the most advanced batteries scarcely put a dent in the massive power demands. The 300 megawatt-hour battery recently unveiled by cruise company Viking would only sustain full propulsion on its small ocean ships for around 40 minutes.
Still, combining batteries with traditional fueled engines in hybrid systems can drive meaningful efficiency gains. When in port, ships can operate services and hoteling solely on battery power. This avoids running dirty auxiliary engines just to keep the lights on.
Carnival's new LNG-battery hybrid Excel class ships save 10-15% in port emissions this way. But far more work remains to achieve true zero emission cruising. Batteries must get drastically cheaper and better before providing primary propulsion. Fuel cells require revolutionary leaps in infrastructure buildout.
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Sustainability Efforts Divide Cruise Lines
The cruise industry is slowly awakening to sustainability, but companies’ efforts remain disjointed and often more about greenwashing than enacting real change. A handful of major players have set ambitious environmental targets, yet lag far behind in making good on promises. At the other end of the spectrum, many smaller lines cling to the status quo of dirty fuels and pollution. This reluctance to invest in new technologies stems largely from the capex-intensive nature of the cruise business. Building green requires billions upfront that publicly traded corporations are loath to sacrifice to shareholders. But customers increasingly demand tangible climate action, not just slick marketing slogans. This growing rift separatesleading innovators from stubborn laggards.
MSC Cruises aims to achieve net carbon neutral operations by 2050. The company is building next-gen environmental ships running on alternative fuels. Its new LNG-powered vessels cut sulfur emissions by 90-95% and nitrogen oxides by 12-15% versus conventional marine fuels. MSC is also researching biofuels, fuel cells and batteries to inch toward decarbonization. Yet LNG provides only incremental gains given its methane slippage. MSC must rapidly escalate efforts to meet its 2050 target.
At the vanguard, Hurtigruten this year banned heavy fuel oil across its fleet. Battery hybrid technology enables the line to sail emissions-free in Norwegian fjords and other sensitive zones. Hurtigruten aims to slash absolute carbon emissions 50% by 2030, mainly via fleet-wide hybrid retrofitting. This tangible commitment contrasts against competitors who simply pledge gradual “improvements.” Still, Hurtigruten acknowledges the immense challenges in fully decarbonizing ocean cruising.
Lagging lines like Carnival and Royal Caribbean set vague, long-term environmental targets without taking concrete near-term action. As recently as 2020, Royal Caribbean’s Celebrity Cruises christened a massive LNG-powered ship. Yet LNG provides marginal gains at best, while locking in fossil fuel dependence. And Carnival’s 2020 sustainability report nostalgically praises exhaust scrubbers as an emissions solution, although they simply dump pollutants into the sea. Until these corporate behemoths take radical steps like banning heavy fuels, their sustainability PR rings hollow.
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Balancing Tourism Jobs and Environment
The cruise industry directly supports over 1 million jobs worldwide, providing incomes for port workers, ship crews, travel agents and more. So communities dependent on tourism dollars may face wrenching tradeoffs between environmental protection and economic livelihoods.
Barcelona's tensions epitomize this dilemma. Cruise tourism contributes €800 million annually to the local economy and supports nearly 7,500 jobs. Over 30,000 Barcelona citizens rely directly or indirectly on cruise visitor spending. Shipyards building for cruise lines employ thousands more.
So when Barcelona's mayor Ada Colau imposed restrictions on cruise tourism to combat overcrowding and pollution, she faced fierce backlash. Port unions protested that her policies cost local jobs. Workers fretted that businesses catering to cruise passengers would suffer.
Yet many citizens staunchly supported Colau's actions to curb environmental damage. Cruise ships frequently double background air pollution levels when docked in Barcelona. Residents complained of black clouds belching from smokestacks and sooty toxins coating their homes whenever ships visited.
Colau tried balancing sustainability and jobs by mandating ships plug into shore power or face restricted access to the port. Yet cruise lines resisted this costly option that still allows some port calls. A protracted standoff persists between authorities prioritizing public health and industry defenders warning of economic impacts.
So when U.S. environmental regulations started requiring ships to switch to cleaner fuels near coastlines, the cruise industry balked. It claimed the costs of using low-sulfur fuels in Alaska would sink smaller cruise lines.
In the end, Alaska reached a compromise. Ships must burn low-sulfur fuels when docked, allowing some visits without forcing full decarbonization. But cruise lines must also chip in to a fund supporting local environmental mitigation projects.
This uneasy détente attempts upholding both the economy and environment. Yet many feel it's not enough. Ships still pollute freely offshore, and full transparency on the environmental impacts fund is lacking.
World's largest cruise ship stokes environmental concerns:Goliath of the Seas: Mega Cruise Ship Raises Concerns Over Environmental Impact - Regulating The Cruise Industry's Footprint
The massive environmental footprint of cruise ships is raising alarms worldwide, yet meaningful regulation remains elusive. International maritime laws grant cruise lines a free pass to pollute without constraint on the open ocean. This regulatory vacuum on the high seas allows unchecked dumping of sewage, greywater and even garbage. Ships burning viscous heavy fuel oil spew lung-searing sulfur and nitrogen oxides. Yet they sail with impunity through international waters, not accountable to any nation’s emissions laws.
Coastal communities do have jurisdiction over ships when docked. But lacking global standards, regulation becomes fragmented across ports. Barcelona banned ships from docking without using shore power. Alaska requires cleaner fuels in port, but not offshore. The United States and Canada prohibit any sewage dumping within three miles of shore. Meanwhile in the EU, sewage discharge is allowed everywhere except for nearshellfish beds. This patchwork approach leaves loopholes for ships to pick their ports of least resistance.
Some jurisdiction confusion also arises because cruise ships are registered under “flags of convenience.” Over three quarters of the fleet sails under the Bahamian flag. But the Bahamas exercises minimal regulatory oversight. Flags of convenience allow cruise lines to skirt tougher labor and environmental laws where companies are actually headquartered.
Advocates urge the International Maritime Organization to implement a global, legally binding treaty capping cruise emissions. But industry resistance has stalled efforts so far. Critics say current IMO standards are mere suggestions cruise lines can voluntarily adopt or ignore. Shadowy corporate structures further complicate accountability. Carnival Corporation wholly owns 10 cruise brands, yet each maintains distinct regulatory reporting. This diffuses responsibility across a tangled web of subsidiaries all under Carnival’s umbrella.
With weak international policing and veiled corporate identities, cruise ships keep operating as unaccountable polluters. Some experts suggest port cities should band together and set strict conditional access policies. By collectively enacting environmental requirements, they avoid cruises re-routing to less regulated havens. United, port authorities can set the bar worldwide.