Three ways to improve commercial shipping’s environmental footprint

A man stretches his leg on the bank of the Han River as a ship passes by amid thick haze. Tens of thousands of premature deaths in east Asia every year are caused by shipping pollution.
REUTERS/Stringer

Martina Doblin, University of Technology Sydney

Do you wear runners, drink coffee or own a mobile phone? The chances are that these products cruised to you on a ship. In 2015, the global merchant fleet carried a record 10 billion tonnes of cargo, a 2.1% increase from the previous year.

However, while it’s an essential part of international trade, shipping also poses serious risks to the environment. Apart from damage caused by dredging shipping channels and the spread of marine pests around the world, there is also growing concern about pollution. According to a report from the European Union, international shipping contributes 2.5% of global greenhouse gas emissions annually. This is predicted to rise by between 50% and 250% by 2050.

As well as contributing to global warming, ship pollution includes toxic compounds and particles that cause a host of other health hazards. A 2016 Chinese-led study found the shipping boom in east Asia has caused tens of thousands of premature deaths a year, largely from heart and lung disease and cancer.

Commercial ships are designed to be used for a long time. As a result, their engines are typically older and less efficient than those used in many other industries, and replacing them is prohibitively expensive. But there are some immediate solutions to this problem that use existing technology: increasing fuel quality, treating engine emissions, and adopting other energy-conservation measures so that ships burn less fuel.

Improve fuel quality

When diesel ship engines burn poor-quality fuel, their smoke stacks release oxides of nitrogen and sulfur as well as carbon. These pollutants, as well as contributing to greenhouse warming, are highly toxic. Sulfur dioxide readily dissolves in water, creating acid rain that causes harm to both people and the environment.

Refinement of crude oil removes sulfur, which reduces the amount of sulfur dioxide produced when the fuel is burned. Higher-grade diesel also reduces the volume of heat-trapping nitrous oxide, but is more expensive to produce because it requires more purification at the refinery.

The International Maritime Organization, the UN body that regulates the safety and security of shipping, is planning to reduce the amount of sulfur allowed in fuel. However, it is currently considering whether the change will take place in 2020 or will be deferred to 2025.

Install exhaust scrubbers

Clean fuel is an important part of reducing emissions, but the higher cost of low-sulfur fuel will deter many companies. Another way for ships to meet clean-air requirements is by capturing engine exhaust and passing it through scrubbers. These scrubbers convert nitrous oxide gases into harmless nitrogen and water.

This process requires retrofitting older ships, and updating the design of new ship exhaust systems. One advantage of this approach is that it allows ships to meet the different pollution regulations around the world without having to swap fuels.

Another way to reduce production of nitrous oxide is by reducing the temperature at which diesel fuel burns, but this leads to decreased fuel efficiency and increased fuel consumption. Scrubbers are potentially a cheaper and more accessible option.

Reduce energy use overall

Ships don’t just burn diesel fuel to propel themselves through the water. Fuel also generates electricity so that people on board can do things like use computers and read at night.

To increase fuel efficiency, other energy conservation measures can be adopted so that ships burn less fuel and decrease their emissions. The US Navy’s Green Fleet has, for example, replaced their old light fixtures with energy-saving LEDs.

They have also undertaken a temperature control initiative, where thermostats have been checked to ensure they are in proper working order and faulty parts in their water cooling systems replaced. Some ships have gone further, and installed stern flaps that modify the flow of water under the ship’s hull to reduce drag, thus increasing fuel efficiency.

All of this means the shipping industry can lower its fuel bill through conserving energy, and at the same time reduce its negative impacts on the health of humans and the planet. With more than 20,000 ships in the global fleet, these immediate solutions to reducing greenhouse gas emissions and other types of pollution will make a real difference.

Martina Doblin, Senior Research Fellow, Plant Functional Biology & Climate Change, University of Technology Sydney

This article was originally published on The Conversation. Read the original article.

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NEW SOUTH WALES NATIONAL PARKS UNDER THREAT???

The New South Wales government is now considering some level of development in the national parks of New South Wales. Just what level of development that may be is yet to be made clear. It is understood that the development may include accommodation projects, various commercial enterprises and guided bush walks.

Tourism Minster Jodi McKay, a former news reader with NBN television, is waiting on a report from a government commissioned taskforce looking into ways that tourism can be increased in the state’s national parks.

The planned tourism development of national parks is a major step away from the ‘wilderness’ goals of recent times and represents a threat to the wilderness values of national parks and world heritage listed areas.

However, a certain level of development may be appropriate, given the serious deterioration of many of the amenities and signage within New South Wales national parks. Many access routes are also seriously degraded following years of poor management.

Perhaps a quality New South Wales national parks and reserves web site could be developed, with the current web site being quite dated and not particularly useful for visitors to the national parks of New South Wales. Quality information on the attractions and access to each national park would greatly improve the tourist potential of New South Wales national parks.

If quality visitor brochures/leaflets on such things as camping facilities, access routes, walking trails and park attractions could be developed and made available via PDF documents on the web site, potential visitors could plan their trips and this would certainly increase visitor numbers to the national parks.

Quality content and relevant up-to-date information on each national park, as well as well maintained access routes and facilities would encourage far more people to visit the national parks and give visitors a memorable experience.

BELOW: Footage of the Warrumbungle National Park in NSW.