Using biodiesel blends can mean cleaner seas for years to come

Jul 5, 2017 by Capt. Jeff Werner

Diesel Digest: by Capt. Jeff Werner

Working aboard a yacht should make every captain and crew member an environmentalist. After all, without clean seas what yacht owner or charter guest would want to go cruising? With worldwide concern about lowering carbon footprints, how can environmentally savvy crew reconcile making a living on a vessel powered by fossil fuel that pumps its exhaust directly into the water? The answer is clean diesel.

Clean diesel technology marries ultra-low-sulfur diesel fuel with highly efficient diesel engines and advanced emission controls to yield near zero pollutants into the water and air compared with a few decades ago.

According to the Diesel Technology Forum, a nonprofit organization dedicated to raising awareness about the importance of diesel engines, fuel and technology, “Diesel is the world’s most efficient internal combustion engine. It provides more power and more fuel efficiency than alternatives such as gasoline, compressed natural gas or liquefied natural gas.” The group points out that a worldwide effort of “innovation and billions of dollars of research and development, engine, vehicle and equipment manufacturers today produce new diesel engines and equipment to meet all the needs of tomorrow’s sustainable world.”

In the maritime field, MARPOL Annex VI addresses air pollution from marine engines on ocean-going vessels. This international convention on pollution from ships limits the amount of emissions from nitrogen oxides, sulfur oxides and particulate matter. Oxides of nitrogen are gases that form when diesel fuel is burned with excess air. Oxides of sulfur are the precursors of acid rain, which has acidified soils, lakes and streams, accelerated corrosion of buildings and monuments, and caused reduced visibility in the atmosphere. The amount of sulfur oxides is directly related to the amount of sulfur contained in diesel fuel. Diesel particulate matter is microscopic particles and liquids that form during the combustion process.

As a result of clean diesel technology, there is a 98 percent reduction in nitrogen oxides and particulate matter emissions from new engines, and a 97 percent reduction in sulfur in new diesel that drastically curtails the production of sulfur oxides.

On the commercial side of the maritime industry, the Diesel Technology Forum states: “Seaports and river ports are home to many marine vessels and harbor craft that help larger vessels

and cruise ships navigate narrow ship channels. Many large seaports are also home to active ferry terminals helping to transport commuters. Inland waterways and Great Lakes ports host a large population of barges and the workboats that propel these crafts. These ferries and workboats are almost exclusively powered by diesel engines.”

Most of these vessels are using older diesel engine technology. Upgrading or replacing these older marine engines has made it the largest category of types of diesel engines to receive federal incentive funding to reduce emissions.

The Diesel Technology Forum also reminds yacht owners, “Today’s diesel technology does more with less, more work with fewer emissions, using less fuel. Additionally, most diesel engines today can run on high-quality blends of biodiesel with little modification, as well as next-generation, renewable diesel fuels which offer even further benefits. According to the U.S. Environmental Protection Agency, biodiesel is classified as an ‘Advanced Biofuel’ capable of reducing greenhouse gas emission by at least 50 percent.”

Biodiesel blends, which are approved for use in marine engines, have at least one advantage over diesel refined from petroleum. Biodiesel has a higher lubricity which results in less wear to parts such as fuel injectors. Traditional diesel fuel uses sulfur for lubrication, and much of that component has been removed from the refined fuel to reduce emissions.

Whether using a biodiesel blend or traditional diesel, a fuel preventive maintenance program is a must. Use of the proper fuel additives and regularly scheduled fuel polishing and tank cleaning will assure that either type fuel is clean and within specifications. But using a biodiesel blend will make a statement about your yacht’s commitment to the marine environment. It can be the first step in becoming a “green” yacht, which will help assure the seas we cruise will be enjoyed for many generations to come.


Capt. Jeff Werner is a 25-year veteran of the yachting industry as a captain on private and charter yachts, both sail and power, and a certified instructor for the RYA, MCA, USCG and US Sailing. He also owns Diesel Doctor ( Comments are welcome at [email protected].