Environment

Calling all ships - Reduce emissions!

Ships are responsible for more than 18 percent of some types of air pollutants. Reducing such emissions is a crucial step in the battle against global climate change. The International Maritime Organization (IMO) and others have estimated that carbon dioxide emissions from shipping were equal to 2.5 percent of the global human-made emissions in 2019. They are expected to rise by 50 to 250 percent before the year 2050 if no action is taken.

Adverse effects of climate change include flooding, severe storms, melting of permafrost and polar ice, and extreme temperatures that make large regions of the world uninhabitable. Solutions are needed without delay.

On the sidelines of the United Nations climate conference in Glasgow in late 2021, emissions from transportation and traffic were discussed by a number of nations – even though such emissions were strictly speaking not on the official agenda. The International Energy Agency has estimated that transportation is one of the most significant sources of greenhouse gas emissions.

Among other countries, Finland pledges to reduce traffic-based emissions in land, sea, and air transports. Representatives of the Finnish government noted after the conference that the Glasgow declarations will affirm Finland’s role as a hightechnology country developing climatefriendly transport solutions. New strategies for implementing coal-free maritime transports were deemed particularly important and urgent.

Coal-Free Shipping

One example of the Glasgow conference initiatives for reducing ship emissions is the Clydebank declaration. It encourages countries to develop coal-free routes for maritime transports, in order to set an example for the rest of the world.

The declaration supports IMO’s actions for reducing ship emissions and strives to demonstrate that certain shipping routes can actually be operated with coal-free fuels, as early as in the next few years.

Although Finland yet has no such coal-free shipping routes, Finnish ships are increasingly being powered by biofuels or by various hybrid – partially electric – powering solutions. Furthermore, Finland’s numerous short-range coastal or ferry routes could have potential for pilot projects for electrically-powered vessels in the near future.

Additionally, Finland is participating in Denmark’s initiative that aims to implement totally greenhouse-gas-free sea transports by the year 2050.

Low Emission – Limited Pollution

In some estimates, maritime transport emits approximately 940 million tons of carbon dioxide emissions annually. Fifteen of the largest mega-ships alone cause as much air pollution as 760 million cars. International shipping is responsible for 87 percent of CO2 emissions in shipping.

Emissions from shipping mainly include sulphur dioxides (SOx), nitrogen dioxides (NOx), particular matter (PM) and carbon dioxide (CO2). Additionally, pollution of seas can be caused by ballast water, waste, plus oil and chemical spills.

Statistically, ships from three flag states – Panama, China and Liberia – are causing the largest CO2 emissions in shipping: 35 percent of the total for all three combined.

Luckily, there is significant potential to reduce shipping emissions cost-effectively. This can be obtained by both technical and operational measures.

The International Maritime Organization is taking steps to reduce greenhouse gas emissions from international shipping. For one thing, sulphur content in shipping fuels is limited to less than 0.5 percent.

As to operational measures, reduction of speed and route optimisation would reduce fuel consumption considerably. By reducing average speeds by 12 percent, daily fuel consumption could be decreased by some 27 percent. Weatherbased route optimisation in shipping can result in further fuel savings of some 3 percent.

Technical measures can also reduce emissions. Possible solutions include propeller optimisation, heat recovery systems, hull designs, and emission filtering.

LNG-Fuelled Cruise Ships

Coal-free powering of vessels is one solution. Innovations in battery technologies are gradually paving way for electrically powered ships, at least for short-range routes. Wind-assist systems are also possible and are already in use aboard some cruise ships.

Today’s environmentally-friendly fuel solutions include LNG (liquefied natural gas) that is already being utilised, even for powering very large cruise ships.

LNG is a practical solution e.g. around the Baltic Sea region where IMO’s environmental regulations have in recent years become very strict. For LNG-fuelled ships, coastal LNG terminals are needed. Such terminals already exist in various countries.

Some cruise ships have dual-fuel systems: while the main fuel of the ship is LNG, the engines may also be able to utilise MGO gas oil or other substitute fuel. Running on LNG, this type of vessel has virtually no SOx emissions and its NOx emissions remain well below IMO regulation levels. The particular-matter and CO2 emissions should also remain on low levels.

Future environmentally-friendly fuel options for ships will also include ammonia and hydrogen fuels.

New Technologies and Innovations

A number of hi-tech innovations that support emission-reduction goals have already been developed by Finnish engineers. For instance, Wärtsilä – known for its ship engines and power plants – is in the process of designing new types of environmentally- friendly engines.

A ship engine running on ammonia- based fuel is about to be launched to the market. Ammonia consists of nitrogen and hydrogen. Burning ammonia will not release CO2 into the atmosphere.

Another ship engine concept utilising pure ammonia fuel is scheduled to be complete in 2023, while ship engines running on pure hydrogen are expected to be launched by 2025.

Two other Finnish companies, Flexens and Elomatic, are now cooperating to presently produce hydrogen and synthetic fuels in Naantali, especially for the maritime fuel markets.

Furthermore, VTT SenseWay has researched into reducing emissions of cruise ships in particular. Approximately one third of the fuel consumption of cruise ships is caused by passenger cabins – the second-largest energy consumption figure, right after propulsion. When a cruise ship is docked, energy consumption of passenger cabins rises to first position.

VTT SenseWay’s intelligent sensor device can be used to limit energy consumption in empty cabins and other areas where there are no passengers present. This matchbox-sized device can be utilised for energy optimisation, but it also can also yield an overview of the locations of passengers, thus assisting rescue work in fire emergencies or other high-risk situations.

The device can be integrated into the ship’s various automation systems. Pilot projects have been scheduled to start in early 2022.

Text by: Ari Mononen
Photos by: Unsplash and Pexels