Tugboat 101: Basic Facts about this Useful Vessel

Tugboats are trusty marine vessels that maneuver much larger ones by towing them. They can range in size from a small 50-foot harbor tug to a larger 250-foot or even bigger, offshore anchor tugs. Owing to their functions, they are made to be extremely powerful despite their size.

Tugboats are basically used to assist ships that should not move by themselves because of the danger of hitting smaller ships in the dock should they attempt to maneuver. They are also used to guide ships that cannot move without assistance because of their size, like huge barges. There are also tugboats for ship and harbor construction.

Aside from those that operate in the sea, there are also river tugboats or push and towboats. These are especially designed to work in the rivers, bayous and other freshwater bodies to transport passengers and cargo through or across. Their hull designs, and the absence of a hawser or winch make ocean operation dangerous.

With these varied functions, tugboats, are without a doubt, among the most important workhorses in the world’s seaports. Recently, hybrid tugboats have started to replace the older tugboats which consume more energy and cause air and water pollution. These hybrid tugboats have lesser carbon emissions, are quieter and more efficient.

Tugboats Now Going Green!

Tugboats may seem the least spectacular among maritime vessels, but pound for pound, they are certainly one of the most powerful. The power of a large tug’s engine can reach up to 4.5 times the tug’s weight. This power is needed for the tugboat’s herculean task of towing and pushing vessels much larger than they are, and navigating them through all kinds of waterways.

The power of tugboats comes from large but lightweight diesel engines that drive the boat’s propellers, and allow them to go straight to full steam from an idle position. Unfortunately, these diesel engines are also a major source of pollution in coastal areas. Efforts are being made, however, to come up with greener tugboats.

Among these, the most notable to date is the hybrid tugboat that also runs on batteries. Instead of powering the boat’s propellers the conventional way, the diesel engine in a hybrid tugboat functions to charge the batteries, which in turn power the boat. The engine turns off once the batteries are fully charged. This results in lower diesel consumption and emission levels.

Exciting new efforts are also underway to build tugboats using greener types of fuel, such as Liquid Natural Gas (LNG). LNG contains less harmful constituents than diesel, and therefore inflicts less harm on the atmosphere.