Skip to main content
RISE logo

Energy-efficient and fossil-free – the shipping of the future

The Swedish shipping industry generates sales of just over SEK 85 billion, indirectly employs 100,000 people and transports more than 170 million tonnes of goods and 67 million passengers – every year.
Now, international regulations require significantly reduced carbon dioxide emissions from shipping. Parallel to this, increasingly more suppliers and subcontractors are making increasingly explicit demands that any sea freight must be both environmentally friendly and economically viable.
Can shipping be made fossil-free? And is society ready for the major transition shipping faces?

Stricter international regulations entail the introduction of concrete, detailed requirements, which come 2050 are to have reduced carbon dioxide emissions from global shipping by 75 percent compared to 2008. Further to this, already by 2030, emissions from shipping are to have been reduced by 40 percent compared to 2008. Shipping is now encompassed by the EU’s emissions trading system, and come 2027, European shipping companies will have to pay for all their carbon dioxide emissions.

“We’ll see rapid developments over the next five years,” says Ellinor Forsström, who works with maritime transportation and logistics systems at RISE. “The green transition is moving way too slowly, and when demands on shipping are tightened, the consequences for society will be major. It won’t be painless.”

From voluntary to necessary

In the past, various measures to improve energy efficiency within shipping have been voluntary, but this is no longer the case. Globally, 99 percent of all ships still run on conventional fuels. What is required now are action plans showing how different routes, speeds and onboard installations can reduce the energy use of each individual ship. It will, however, take more than this.

“The industry will gain momentum once carbon dioxide emissions come at a price,” says Forsström. “Interest in alternative fuels will increase, but the technologies to enable alternative fuels are still largely based on technologies that haven’t yet reached market maturity. We’ll see increased research activity now that economic carrots and sticks are putting a price on emissions.”

These stricter shipping regulations entail both economic and technical challenges. Within the EU, emissions trading will probably increase. An economic reward and penalty system could be regulated by, say, reduced or increased port charges. Many shipowners will need to modify onboard installations to achieve more efficient energy use.

“The transition within shipping will have major consequences for land-based energy systems as well,” Forsström continues. “Large volumes of alternative fuels need to be handled and distributed to ships, and there’ll be greater demand for shore-side electricity. The shipping industry has been aware of the green transition for some time, but the effects on the land side will come as a shock to the rest of society.”

Alternative fuels

Both shipping and society face a growing need for more knowledge about alternative fuels. All alternative fuels are more expensive than conventional fossil-based shipping fuels. If you ask which fuel is most suitable, the simple answer is: It depends. The ship’s design, route and particular use are some of the factors that come into play.

  • HVO stands for hydrogenated vegetable oil, which is a so-called drop-in fuel that can be mixed with normal diesel. One advantage is that you can use existing fuel infrastructure and existing engines. One disadvantage is that it is difficult to get hold of and is relatively expensive.
  • Methanol can be produced in a sustainable manner and is a relatively cheap alternative fuel. Sweden was the first country in the world to use methanol as a shipping fuel.
  • Biogas is a drop-in alternative for ships that run on LNG, liquefied natural gas. Within a couple of years, there may be a real possibility of replacing fossil LNG with renewable liquid methane from Swedish biogas plants.
  • Ammonia as a potential shipping fuel is another major research line, as is hydrogen.

“Gaseous fuels like ammonia and hydrogen are more complicated than liquid fuels to handle on board, but we’re working to find safe solutions,” says Joanne Ellis, a senior researcher with a focus on alternative fuels. “A gas leak on board could be devastating, so we’re working hard to develop various safety systems.”

Can shipping be electrified in the same manner as the land-based transportation of people and goods?

“Yes, but not over such long distances. The major challenge for shipping is that the distances are often extremely long. Access to additional electricity is limited, and powering a ship takes a great deal of energy. Electricity is an excellent alternative for shorter routes.”

A ship can take advantage of the wind in different ways

Wind as an energy source

The use of wind as an energy source has seen some significant investments, and Sweden is a world leader when it comes to technology development for the wind propulsion of large ships. The vision is to have ships powered solely by wind propulsion in the future.

“A ship can take advantage of the wind in different ways, and each case is unique,” says Sofia Werner, Lead Researcher Hydrodynamics and Wind Powered Ships at RISE. “Should you use wings, sails, rotors or something else? How does this affect costs, transport times, routes and availability? Are there any risks? And which regulations apply? We have unique and well-refined methods for answering these questions.”

At present, there are twenty-four merchant ships in the world using some form of wind-assisted propulsion. And this is a rapidly growing industry. According to a forecast made by the EU, come 2050, there will be 40,000 wind-powered ships in the world.

The question Werner and her colleagues most frequently hear is: How big are the fuel savings? And here, too, the answer is: It depends.

“There’s no simple answer,” says Werner. “And that’s a difficult answer for the shipowners who need to make decisions. Just how big the potential savings are is difficult to say, as it depends on the circumstances and the technology used. Routes with strong winds offer major fuel savings. Savings of up to 90 percent are possible, but then we need to modify the business models used at every stage. Cargo owners and consumers alike must rethink their demands in terms of delivery time and delivery precision.”

RISE supports the entire industry by comparing different technologies, analysing and recommending various solutions for each particular case that will prove cost-effective while also reducing emissions. The Swedish maritime industry is at the forefront when it comes to developing technical solutions for reducing emissions. And this will be a major competitive advantage in the future.

Some 90 percent of all international freight is transported by sea at some point. In 2019, shipping accounted for between three and four percent of the EU’s total carbon dioxide emissions. A number of international agreements require measures to mitigate pollution from ships.

  • EEDI (Energy Efficiency Design Index) sets out energy efficiency requirements for new ships.
  • EEXI (Energy Efficiency Existing Ship Index) sets out requirements for older ships, such as for following up and classifying the ship’s operational emissions on an annual basis.
  • SEEMP (Ship Energy Efficiency Management Plan) can be compared to an energy declaration for a building. Mandatory for all ships operating in international traffic with a gross tonnage (the ship’s overall internal volume) exceeding 5,000. 
  • FuelEU Maritime comprises guidelines encouraging the use of renewable and low-carbon fuels.

Contact person

Ellinor Forsström


+46 10 516 55 91

Read more about Ellinor

Contact Ellinor
This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.

* Mandatory By submitting the form, RISE will process your personal data.