Unfortunately, the cruise industry suffers constant media pressure based on outdated stereotypes, one of which directly portrays ships as massive emitters of waste and pollution. While the industry has always been environmentally conscious, technological and infrastructural developments in recent years have enabled a huge leap forward.
Article from CruisesNews magazine
Legislation, on the one hand, and technological advances, on the other, are allowing the industry to boast about its environmental commitment. Cruise ships are now being built equipped with gas scrubbers, wastewater treatment plants, water purification systems, and antifouling paints for the hull that reduce both friction and fuel consumption.
Emissions to the atmosphere:
Cruise ships, like most large merchant vessels, consume marine fuel oil, the combustion of which generates sulfur oxides (SOx), a pollutant that, in contact with atmospheric moisture, produces acid rain. In addition, there are emissions of CO, CO2, nitrogen oxides (NOx), and particulate matter (PM).
All solid waste is sorted and unloaded at the port.
Sulfur dioxide (SOx) and nitrogen oxide (NOx) emissions are the most concerning. Therefore, Annex VI of the MARPOL Convention established limits that began to take effect on May 19, 2005, setting an increasingly restrictive timetable. At the same time, four Emission Control Areas (ECAs) were created, with even stricter limits.
Since 2015, any cruise ship wishing to sail in two such important areas as the Caribbean and Northern Europe/Baltic can only emit 0.1% SOx. Furthermore, if the ship was built after 2016, its engines must comply with NOx emission limits according to Tier III specifications. An engine that meets Tier III standards emits less than a quarter of the NOx of Tier II engines manufactured from January 2011 onwards, and less than a fifth of the NOx of Tier I engines manufactured since 2000.
The bad news is that Tier III limits only apply to ECA zones; outside of these zones, Tier II standards apply.
For a boat or cruise ship sailing only outside ECA zones, the restrictions haven't improved as much, dropping from 4.5% SOx in 2007 to the current 3.5%, and from Tier I to Tier II in engine NOx emissions.
The Mediterranean is not an ECA zone, nor does it seem likely to become one in the medium term, although some are calling for its creation by 2020, coinciding with the entry into force of the new SOx limits. It should be noted, in any case, that the proposed 0.5% SOx limit will be reviewed in 2018, and if it is determined that there is insufficient availability of low-sulfur fuel, it will be postponed until 2025. However, along the entire European coast, including the Mediterranean, European Directive 2012/33/EU is in force, stipulating that passenger ships operating mainly near the coast or in European ports must use fuel with a maximum of 1.5% sulfur while underway, and 0.10% while moored in port. In 2020, the European directive will be harmonized with MARPOL, and the limit while underway will be 0.5%.
Thus, in Europe, we would have only two situations: the Baltic Sea (ECA area), 0.1% SOx, and the rest of the European area, 1.5% SOx. This is a much better situation than in 2007, for example.
Given these limitations, and since the Caribbean is an ECA zone and a large number of cruise ships operate there, if not year-round, at least during the winter, cruise lines have had to adapt quickly, and there are only three options for doing so:
– Using low-sulfur fuel oil (MGO), but its price is 55% higher than regular fuel oil, and it is not widely available.
– Installing gas scrubbers.
– Building ships with liquefied natural gas (LNG) engines, which do not generate SOx or PM emissions, and have very low levels of NOx, although there is also limited refueling infrastructure in the ports.
Much of the progress has been implemented in the last five years.
Most cruise lines have opted to install gas scrubbers on their ships, both new and older vessels, an option only available since the IMO (International Maritime Organization) approved it in 2008. These scrubbers eliminate up to 90% of SOx and particulate matter (PM) emissions, which are very harmful to human health.
Carnival Corporation, owner of cruise lines such as Costa Cruises, Holland America Line, and many others, announced in 2014 a $400 million investment to equip more than 70 of its 102 ships with gas scrubbers over the following three years. Royal Caribbean also announced the installation of gas scrubbers on 13 of its ships between 2015 and 2017, and Norwegian Cruise Line had been installing them on seven of its ships through 2016.
Regarding the use of liquefied natural gas (LNG) as fuel, it faces several obstacles, including its limited availability at ports for refueling, as well as the large volume of onboard tanks. The size of LNG tanks far exceeds that of fuel oil tanks; therefore, the first ships designed for this fuel had to overcome this challenge.
Regulations regarding the discharge of water into the sea are much more lax, but the cruise industry has imposed limitations on itself.
The Carnival group has made the strongest commitment to this fuel, ordering seven LNG-powered ships for AIDA, Costa Cruises, Carnival, and P&O. These ships, to be built by Meyer Werft, will be available starting in 2019 and will be giants of 180,000 gross registered tons. MSC Cruises has also signed a letter of intent with STX France to build four 200,000-ton LNG-powered ships, to be delivered starting in 2022. These represent 11 of the 66 ships currently on order, or 16.66%, but they clearly point the way forward, at least for mega-ships.
Of course, another way to reduce emissions is to reduce the ship's energy consumption. In this regard, all shipping companies are progressively adopting measures such as switching to LED lighting, turning off the air conditioning when leaving the cabin, heat recovery, bow bulbs, and hull paints that reduce friction, etc.
Shore power – cold ironing.
An alternative to emissions while cruise ships are in port would be connecting the ship to the shore power grid, known as “shore power” or “cold ironing.” There are numerous problems with implementing this solution:
There is no defined standard for connection, voltage, and frequency.
Given the power requirements of a large cruise ship, an electrical substation must be built in or near the port, requiring a significant investment with a difficult return on investment.
Nothing guarantees that the energy supplied to the ship will be cleaner than the energy the ship itself can generate. In other words, the energy generated on land could come from a coal-fired power plant. Or it could come from a nuclear power plant, which has no emissions into the atmosphere but generates nuclear waste—solving one problem and creating another.
Despite all this, the concept is gaining acceptance and development, and there are already several ships with the technology installed, such as the Norwegian Star and the Norwegian Jewel, as well as many others with pre-installation. Many ports are also investing in feasibility studies, as Directive 2014/94/EU sets a deadline of 2025 for European ports to have LNG supplies and electricity supply infrastructure for ships: “unless there is no demand or the costs are disproportionate to the benefits, including environmental benefits.”
Black and Greywater:
The wording of Annex IV of the MARPOL Convention is quite convoluted. Although it starts off well by stating that "the discharge of blackwater into the sea is prohibited," the reality is that the exceptions section includes a very significant one that allows the discharge of untreated blackwater into the sea, provided it is done en route more than 12 miles from the coast, at a minimum speed of 4 knots, and at a certain rate.
If the ship has a blackwater treatment plant that grinds and disinfects the waste, it can discharge as close as 3 miles from the coast.
The main environmental effort is being made to reduce emissions into the atmosphere.
The Baltic Sea is theoretically a special zone where passenger ships cannot discharge sewage unless they have a treatment plant that meets the strictest regulations, including limits on nitrogen and phosphorus content. However, the reality is that this regulation will not come into effect until all countries bordering the Baltic accept resolution MEPC.227(64) and provide sewage discharge facilities for ships without their own treatment plants.
The good news is that since 2011, CLIA, the association that unites the vast majority of cruise lines, has mandated that all ships belonging to its member companies will not discharge untreated sewage anywhere in the world. For treated sewage and greywater, the commitment is to not discharge within 4 nautical miles of shore and at a minimum speed of 6 knots.
Ballast and Bilge Water:
Ballast tanks can take in water at one point and release it hundreds or thousands of kilometers later. This water contains microorganisms, bacteria, and plants that can disrupt the ecosystem where it is discharged. The IMO created regulations on these discharges in 2004, but unfortunately, they have not been ratified by enough countries to come into effect.
However, some cruise ships comply with Lloyd's Register's "Environmental Protection Class Notation" certification, which includes pre-treatment of ballast water, pool water, and bilge water before discharge, as well as the use of environmentally friendly antifouling hull paints.
All solid waste is sorted and unloaded at the port.
Regarding bilge water, where traces of water and oil are mixed, its discharge is generally prohibited, unless it is treated with oil filters that minimize the oil contained in the discharge to 15 parts per million.
Solid waste:
The MARPOL Convention, in Annex V, also stipulates how ship waste must be treated. Of course, it is prohibited to dump plastic waste, household garbage, cooking oil, and incineration ash into the sea.
Glass, cans, cardboard, oils, and other materials:
Glass, cans, and cardboard waste are sorted and compacted, then unloaded for sale to recycling plants at the port. Ports are obligated to facilitate this unloading.
Food:
Food scraps are processed through a process of shredding, drying, and compacting. The resulting waste can be incinerated on board or discharged at sea when the ship is sailing more than 3 miles from the coast, or 12 miles if it is in a designated area. Although some optimistically refer to this as "fish food," the truth is that, on the one hand, these food scraps are not the most suitable for feeding wild fish, and on the other hand, the constant discharge of food scraps on certain cruise routes can create environmental problems in the area.
Liquefied natural gas is emerging as a fuel for the cruise ships of the future.
The Mediterranean, Baltic, North Sea and Caribbean are considered special areas regarding garbage disposal, so only crushed food and cleaning products washed away by water from cleaning decks and windows can be discharged into the sea.
Tours:
Environmental awareness is starting to extend even to excursions, and Royal Caribbean will classify tours based on its GSTC (Global Sustainable Tourism Council) certification so that passengers can make informed decisions about which tour to take, increasing the pressure on tour operators to offer increasingly eco-friendly excursions.
Cruises: A Conscious Industry.
With all the legislative pressure of recent decades, but above all, with millions of passengers increasingly concerned about the environment, the cruise industry has recognized that it must constantly invest in reducing its environmental impact, sometimes taking measures that exceed legal requirements.
It must be said that much of this progress has been implemented, and is being implemented, in less than a decade, practically in the last five years. Therefore, it is crucial to communicate these industry efforts much more effectively to passengers to correct some misconceptions that persist in the collective imagination. Cruises are definitely not a factory of garbage and pollution that is freely scattered across the seas; quite the contrary, it is one of the most responsible tourism industries, considering its unique characteristics.
