But the technology was not yet sufficiently mature and the batteries were too heavy. The boat had room for 25 passengers and sailed along the river Spree at 14 km/h. The City of Berlin in Germany tested it for local public transport. This was followed in 1886 by the “Elektra”, a test boat from Siemens & Halske. The first electric boat was tested on the St. In the future, the electric engine could also be supplied with energy by other means, such as with rechargeable batteries, liquefied natural gas (LNG) or solar power. In this case, the energy comes from the batteries on board. This is the case only if the ship can sail without the diesel engines running, at least for a certain length of time. But this is still not a hybrid drive system. This translates into reduced energy loss and higher efficiency. The electrical machines also consist of fewer components, are less prone to faults, and have less wear and tear. This has many advantages: It saves between five and 20 percent of the fuel. Diesel generators generate the electricity, which then drives the electric engine.
The engine or a generator also generates electricity for all the electrical systems on the ship.īut for several years, many ships have been partly electrified: 80 percent of oceangoing ships now use a diesel-electric transmission system. Traditionally, this type of drive is mechanical: The diesel engine drives a shaft that then moves the ship’s propeller. They burn fossil fuels – diesel, heavy oil, gas oil. After the invention of steam engines and turbines, diesel engines in various forms were also used in the 20th century. But from the start of the 19th century, this task was increasingly taken over by engines.
Ships were driven by the wind for thousands of years. The figure could reach $20 billion by 2027.
Because of this, the analysts at IDTechEx predict that worldwide sales of fully electric and hybrid ships will increase. One advantage of battery operation is that electricity is much cheaper than oil and, especially, marine diesel. In many cases, the environmentally friendly alternatives to oil are suitable for inland shipping – and also for oceangoing ships in the distant future. Electrical drive systems are not just deemed to be sustainable on land and in the air. This is why the use of other energy sources is more efficient and cleaner, such as liquefied natural gas (LNG), hydrogen, or electric energy. However, the mineral oil from which diesel is produced could be exhausted in 50 years at the current rate of consumption. Besides, both of these options have a significant disadvantage: They are based on an internal combustion engine and, consequently, fossil fuels. Marine diesel contains much less sulfur, but is much more expensive. Or the ships could use marine diesel instead of the extremely dirty heavy oil. These separate harmful nitrogen oxides into nitrogen and oxygen and a soot filter retains particulate matter.
But what options are available to reduce emissions? There are various possibilities: For example, ships could install catalytic converters, similar to cars.
If the ambitious plan is to succeed, a change of thinking will be required. This puts at risk the targets of the Paris Climate Agreement, which specifies limiting global warming to well below two percent. A study by the EU parliament also assumes that by 2050 maritime traffic will be responsible for almost a fifth of global CO 2 emissions. By 2050, air pollution could rise by at least 50 percent in the worst-case scenario, even by up to 250 percent. The problem will get worse if conventional energies continue to be used as in the past. There are health risks – from asthma in children to premature death. The exhaust gases have disastrous consequences for the environment: The world’s climate is changing, the oceans are acidifying. In addition, fewer dangerous nitrogen oxides are emitted.
In inland shipping, on the other hand, marine diesel is used as a fuel, which is less harmful than heavy oil when it is combusted. And they consume enormous amounts: Together, the 90,000 ships worldwide burn 370 million tons of fuel each year – and produce 20 million tons of sulfur oxide. Most container and cruise ships, oil tankers, and cargo vessels run on heavy diesel oil.