Smoke on the Water

By Bryce Bower, Staff Writer

Courtesy of Quora

Whether or not you believe in climate change, it is a fact that the earth has gotten warmer in the last century. According to NASA, the global temperature has risen 1.7 degrees Fahrenheit (0.94 Celsius) since 1880. The air and oceans are becoming more saturated with pollutants like carbon dioxide, nitric oxide, sulfur oxide, and fine particles. Inhalation of sulfur dioxide can cause difficulty breathing, lung disease, and premature death. Nitric oxide depletes ozone and contributes to the creation of acid rain. Fine particles, like PM 2.5, are too small for our lungs to filter and can seep into our bloodstream causing cardiovascular disease, among other things. These specific pollutants are by-products of burning fuel to power engines, and what is most surprising is that the leading perpetrator is not cars—but ships.

The 16 biggest ships in the world, whether cargo hauler or cruise ship, produce more sulfuric oxides, nitric oxides, and fine particles than the estimated 800 million cars on earth. This is because they burn a different type of fuel, one that emits 100 times as much sulfur as diesel that is used in the engine of a pickup truck.  I find it very hard to concretely conceptualize the amount of fuel that is being used by these cargo ships. The world’s largest cruise ship, Harmony of the Sea, has two brand new extremely fuel efficient 40-foot high, 16-cylinder Wärtsilä engines. Running on full power, one engine alone consumes 1,377 gallons (5,213 litres) of fuel in one hour. That sounds like a ridiculous amount of fuel, but it’s not so ludicrous when you consider that the ship holds almost 9,000 people, has 16 levels, and when fully loaded can carry 44,612,743 pounds (20,236,000 kg)! This 44 million doesn’t even include the weight of the ship itself. As I was exploring this topic, I read some posts by a naval architect who claimed the Wärtsilä 46F was one of the most efficient and clean engines of its size.  When hauling millions of pounds around on floating metal, fuel efficiency is key. 1 or 2 percent better efficiency can save millions of gallons in the lifetime of a ship. The Harmony has solar panel and diesel electric power from generators—”the marine equivalent of a hybrid car”—and STILL uses that much fuel.

Actual size of one engine! Courtesy of Mechanics Hub

Europe’s coastal citizens have had to deal with the some of the worst environmental effects of large ships sitting in their ports.  The European Federation for Transport and Environment estimates that air pollution from international shipping leads to the premature death of 50,000 Europeans per year. The air has gotten so bad that a legal environmental activist group has taken the UK government to high court for the second time. Cities that don’t even have heavy manufacturing or large populations are going over the EU limit of pollutants because of their ports.  Many ports across the world now have policies in place where a ship must use low-sulfur fuel within 200 miles of the shoreline. If ships want to weigh anchor, they must comply with this regulation. According to The Guardian, even using low-sulfur fuel, a few large ships at dock still produce enough pollution to cause hospitals to receive a noticeable increase in patients with respiratory problems.

The problem is that International Maritime Law has a much looser limit on emissions than the laws that govern automobiles, and cleaner boat fuel is a lot more expensive to purchase than the sulfur saturated kind. What adds to the problem is that concerned groups have had a very difficult time getting the International Maritime Organization (IMO) to enforce stricter emissions regulations. The biggest concern is the exhaust that comes from these monstrous engines. According to German newspaper Deutsche Welle, as of Jan. 1 2017, not a single cruise ship has had a particle filter installed. Many cruise lines have pledged to install them but have not yet complied, and they are under no pressure from the IMO to do so. So until then, cruise passengers will just have to breathe air with 19 times more fine particles than the air on a heavily trafficked street.

Courtesy of DW

There is good news, as scientists have been looking for ways to cut hazardous exhaust with methods that are economically reasonable. Supposedly, between the year 2020 and 2023 sulfur emission regulations will come into effect. Exhaust scrubbers are already in place in most ships, but the fumes are so thick that even after the air is cleaned it is still heavily saturated with nitric and sulfuric compounds. The problem scientists have faced is creating something that can span the portal of a smoke stack- a microscopic filter that could cover the area of a modest swimming pool. A polytechnic school in Lausanne, Switzerland is using a method that was discovered in the particle accelerators at CERN. They cut titanium into super thin strips, coat them with substances that trap poisonous gasses, and space them unbelievably close together so every molecule has to pass between these “gates”, so to speak. The challenge here is making it affordable, but the science behind it has already come a long way. Assuming cruise lines follow through with what they promised and the IMO gets its act together, we can look forward to a cleaner future.

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