Marine Propulsion and the Latest Advances

March 2, 2015 - 10:26 AM by Samantha Pudney

The science of marine propulsion has been evolving since the first canoe was paddled. You might think that after finding one great propeller, you’ll never need to look again, but new technology is always improving the quality of propulsion.


Marine engineers are coming out with new ways to increase speed of shipping vessels and fleets while not damaging the vessel or the environment. Check out some of these new advances and options for your vessel or fleet:

  • Liquefied Natural Gas (LNG): This model utilizes the traditional propeller, but rather than using diesel, the engine runs on liquefied natural gas, an alternative fuel that has recently become popular with vessels in the United States and the United Kingdom. Because it should go a little faster, your financial returns should be a little higher. In addition, LNG is considered green and will emit a lot less harmful emissions than regular fossil fuels.
  • Duel Fuel Engines: Why only use one fuel type when you can utilize some of the benefits from all three? Having a duel engine will allow you to use a combination of heavy oil, LGN and marine grade diesel to optimize your propulsion. By relying on these three options instead of only diesel, you’ll benefit in several ways. Not only will you have greater fuel efficiency, but you’ll also be eligible for certain tax reductions and other useful savings with this hybrid approach. From a purely operational standpoint, it’s always good to have a backup method of power should one of them fail.
  • Electric Engines: Often heralded as the future of environmentally friendly marine propulsion, electric engines are gaining interest quickly. Rolls Royce, for example, is looking into constructing electric marine propulsion systems in the hopes that vessels and fleets will run quick, more effectively and best of all, quieter.

Now let’s look at these options in more detail and see what can be done.

Pros and Cons of LNG

This method is the “clean” version of propulsion and is reliable and efficient. LNG has several big advantages over other forms of energy. First, it leaves no unburned residue, soot or particles, making it a clean-burning fuel. Fewer greenhouse gases are released into the air as a result. Second, LNG has a high calorific value, which simply means that it generates a lot of energy.

One of the biggest problems facing LNG is that many ships are not candidates for LNG fuel. As this is newer technology, the number of ships using LNG is small, and most of them are located in the Baltic and North Seas and the English Channel. That, however, may change. A report from Gas Technology says more LNG ships are being ordered for the North American region, now that the U.S. Environmental Protection Agency has set regulations for the ships.

Other problems, such the level of sulfur content, face LNG, but engineers are optimistic. International guidelines are in the works now, and more ports that house LNG are scheduled to be developed. This may be a new trend of the future.

Duel Engine Hybrids and their Potential

the Viking Lady

The Viking Lady shipping vessel. Photo: Ships and Oil.

When most people think of hybrids, they probably think of Toyota’s famous hybrid car, the Prius, but hybrids are no longer just for cars. In fact, the first hybrid vessel is currently sailing at this time, a Norwegian shipping company’s Viking Lady.

Duel engines cannot run on natural gas alone, but by using more natural gas and less diesel fuel, these engines have the potential to reduce pollution and provide a greener option for ships.

The United States is already making headway in the use of duel engines. Their production and use is already being regulated, and the American company Matson Navigation recently ordered two of the largest duel engines to be built. These engines were designed with environmental factors in mind and will give operators the option to use natural gas, methanol or a similar LNG. They are scheduled to be completed in 2018.

Although there are still questions of safety, duel engines are already making a splash in the shipping business. As fossil fuel level decrease, vessels and fleets will have to seek out alternative ways to power themselves. Hybrid duel engines may be a pliable solution.

Shocking Electrical Engines

It must be difficult to imagine a huge shipping vessel run by a large battery, but this could very well be the future of marine propulsion as we know it. Since their discovery in 1986, the electrical engine’s power hasn’t quite been harnessed yet, but engineers have made great strides improving the electrical engine, and it might be worth it.

Electrical engines are usually smaller and denser than the conventional motors. At a glance, the conventional motor gives about five kw/kg, but the electrical engine gives a whooping thirty kw/kg, which is a whole lot faster and more efficient. Because the electrical engines are so much quieter, they have been attracting attentions of navies around the world.

At the moment, there are no superconducting electrical motors being used on ships, but in January 2009, the American Superconductor Corporation teamed up with the Northrop Grumman Corporation to construct a full-powered land-based superconducting engine. The final product was less than half the size and weight of its rival, the conventional motor, with the same powering.

One of the biggest problems electrical engines face is their cost. They are expensive to manufacture. Despite being discovered over twenty years ago, the research of the engine’s potential is still in the fundamental stage. It may be a long time before this method of propulsion is viable.


Regardless of where technology is in the development process, it’s always a good idea to keep track of new methods of propulsion. You want to continue to improve your business and keep ahead of the competition. Make a point to update yourself as often as possible or your competition just might pass you by.