Using Technology to Keep Air Clean
The cruise industry is advancing a strong sustainability agenda, reducing emissions at sea and in port—with an increasing number of vessels sailing today using alternative fuels plus ships launching over the next five years that will either use alternative fuels or will be able to incorporate low- and zero-carbon fuels when they become available at scale. Additionally, cruise ships employ a variety of environmental practices and advanced technologies to significantly reduce emissions including the use of Exhaust Gas Cleaning Systems. Alaska cruise vessels also use onboard opacity-monitoring technology to observe air emissions and data collected is useful in allowing environmental engineers to continue to improve their air systems. These environmental practices and technologies are built on verifiable, scientific facts.
Shoreside Power
Juneau, in partnership with the cruise industry, has long been a leader in environmental protection innovations and was the first port in the world to install shore power. Since 2001, ships at the Franklin Dock reduce emissions by plugging into the city’s hydroelectric power. This practice, which results in a significant reduction in fuel emissions, has been adopted by cruise ports around the world.
Shore power is available at the new dock in Whittier and will be available in Seward once the existing railroad dock has been replaced.
Exhaust Gas Cleaning Systems
In addition to the work the cruise industry is doing to further reduce emissions, it’s also important to note that ships must comply with the air quality requirements of the International Convention for the Prevention of Pollution from Ships (MARPOL). The use of Exhaust Gas Cleaning Systems (EGCS) – or scrubbers – is validated by credible science. Several studies have been performed that have specifically analyzed wastewater discharges. The following studies are all distinguished by significant data and use of established methods, and address common questions about EGCS discharge water quality, the accumulations from discharge water in ports, and marine life:
- Puget Sound Exhaust Gas Cleaning System (EGCS) washwater ecological risk assessment: Provides information on a risk assessment of open loop exhaust gas cleaning system (EGCS) washwater discharges from cruise ships within the Puget Sound region of the United States as presented by the study team based on the recommended methodology provided in the 2022 Guidelines for risk and impact assessments of the discharge water from exhaust gas cleaning systems (MEPC.1/Circ.899). WET test results suggest that chemistry-based toxicity predictions (e.g. TLM) are inherently conservative and may overstate cumulative risks when compared to observed results from laboratory-based empirical toxicity tests and MAMPEC modeling showed no significant increase of predicted environmental concentrations above the background concentrations of receiving waters. Technical review of the study is ongoing.
- A CE Delft report (link), which analyzed approximately 300 EGCS washwater samples and concluded that the washwater samples were well within stringent European water quality standards.
- In addition, DNV GL conducted a two-year study that found washwater samples from 53 cruise ships equipped with EGCS to be below the limits set by major international water quality standards.
- Another recent study, conducted by the Japanese Ministry of Land, Infrastructure, Transport and Tourism, found the impact of scrubbers on water quality and marine life to be negligible.
- And, most recently, the Netherlands study at the link here indicates that Wash water from EGCs has negligible impact on environment: New Study (croceanx.com).
- These systems are a recognized alternative to the use of low-sulphur fuels because they are designed to remove the emission components that are deemed harmful. Even though heavy fuel oil can continue to be burned in ships’ engines, the EGCS results in emissions that are equivalent or better than otherwise compliant fuel.
- The IMO has established performance requirements for EGCS. In the U.S., these are further strengthened by EPA requirements – through the Vessel General Permit and the Vessel Incidental Discharge Act.
- When EGCS are operating in ports, the washwater monitoring and recording is a continuous process. Values monitored and recorded include pH, PAH, turbidity, and temperature. These values, including PH, are set by regulation, and are continuously monitored to ensure compliance.
- Residues generated by EGCS are required to be disposed of ashore at adequate reception facilities. They are not to be discharged to the sea or incinerated onboard. The storage and disposal of washwater residues should be recorded in a logbook, which includes the date, time, and location of disposal.