Decarbonisation in shipping

Wärtsilä is one of the leading companies globally offering specialised ship decarbonisation consulting services for both existing vessels and newbuild projects. Through our Decarbonisation Services, we help ship owners, operators, and fleet managers build a clear, data‑driven roadmap to reduce emissions, comply with IMO and EU requirements, and future‑proof their assets.

Our consulting approach combines technical expertise, operational insights, and advanced modelling tools, including:

• Fleet‑wide decarbonisation assessments
  Identifying the most effective and economically viable upgrade paths for each vessel.
• Operational and voyage optimisation analysis
  Using digital tools and real‑world data to reduce fuel consumption and emissions.
• Fuel and technology pathway evaluation
  Comparing alternative fuels (LNG, methanol, ammonia, biofuels) and hybrid/electric options.
• Emission abatement and compliance strategies
  Ensuring readiness for regulations like EEXI, CII, EU ETS, and FuelEU Maritime.
• Newbuild decarbonisation planning
  Helping yards and owners design vessels that are efficient today and ready for future fuels.

Wärtsilä’s experts will work closely with the customer to develop a tailored decarbonisation plan that balances regulatory requirements, financial performance, and long‑term sustainability goals.

Learn more: Wärtsilä Decarbonisation Services

The most promising future fuel options include methanol, ammonia, hydrogen, biofuels, LNG, emerging e-fuels, and blends of fossil and bio/e-fuels.

Each has unique benefits and challenges in terms of emissions, cost, and infrastructure readiness. You will find a handy summary ”Fuel options at a glance” on this page.

Fuel-flexibility is important because no single fuel will dominate the market, and vessels may need to switch fuels during their lifetime.

The latest technologies include Wärtsilä’s solutions for maritime decarbonisation and emissions reduction on three pathways:

Making vessels and operations more efficient. Energy-saving technologies (ESTs), engine upgrades and ship electrification are three possibilities to achieve this, and there are many more.

Adopting and using alternative energy sources. Future-proof, fuel-flexible, multi-fuel engines are a great example of this, and hybrid solutions are another example.

Cleaning up emissions. If a ship cannot run on alternative fuels, the smart choice is to clean up its emissions, and onboard carbon capture is one possible method.

Different vessels benefit from a different combination of innovative technologies to decarbonise. That is why Wärtsilä’s Decarbonisation Services, will build a clear, data driven roadmap for each case, to decarbonise and reduce emissions in an optimal way.

Recent developments in global maritime decarbonisation efforts include ambitious regulatory pushes, technological advancements, and increasing industry adoption of low-emission solutions.

Regulatory pushes and policy moves

• IMO GHG Strategy and Net-Zero Framework: The International Maritime Organization (IMO) has set a net-zero target for greenhouse gas (GHG) emissions from international shipping by or around 2050.
• EU Emissions Trading System (ETS): Since January 2024, the EU ETS has been extended to cover CO2 emissions from large ships calling at EU ports, regardless of their flag. This requires shipping companies to purchase and surrender emission allowances, incentivizing decarbonisation efforts.
• FuelEU Maritime regulation: This EU regulation, which became fully applicable in January 2025, sets maximum limits for the greenhouse gas intensity of energy used by ships calling at European ports, encouraging the adoption of renewable and low-carbon fuels.
• National and Regional Initiatives: Many countries and regions are developing their own maritime decarbonisation strategies and action plans, often aligning with or exceeding international goals.

Technological advancements and industry initiatives

• Measures like integrated, optimised ship design, using digital tools for voyage optimisation and implementing just-in-time arrivals will help reduce fuel consumption and improve operational efficiency.
• Orders for vessels capable of operating on alternative fuels like methanol or ammonia are increasing. Methanol-fuelled vessels are currently leading in the order book, and LNG continues to be important.
• Projects involving battery-powered vessels and wind-assisted propulsion systems are advancing.
• Full-scale onboard carbon capture is in operation: Solvang’s Clipper Eris retrofit with Wärtsilä’s solution has demonstrated ~70% CO₂ capture in operation.

Industry collaboration

• Alliances and initiatives are forming to accelerate decarbonisation efforts, including collaborations between shipowners, fuel providers, ports, and regulators.

The International Maritime Organization (IMO): IMO has set a net-zero target for greenhouse gas (GHG) emissions from international shipping by 2050. There is a firm reduction checkpoint of 20–30% by 2030 and another of 70–80% by 2040.

EU Emissions Trading System, EU ETS: From 1 January 2026, shipping companies must account for 100% of verified CO₂ emissions from voyages to/from EU and EEA ports, up from 70% in 2025. The ETS also covers methane and nitrous oxide, which increases exposure for LNG-fuelled vessels.

FuelEU Maritime: Sets annual well-to-wake greenhouse gas intensity limits. Started with a 2% reduction in 2025, with tightening limits through 2030.

Wärtsilä offers tailored decarbonisation solutions for existing vessel fleets as well as for newbuild vessels.

Wärtsilä is a global leader in maritime decarbonisation technologies, with an offering that covers all three pathways of the maritime decarbonisation journey: 

• Making vessels and operations more efficient
• Adopting and using alternative energy sources
• Cleaning up emissions

Collaboration plays a vital part in driving the sustainable transformation of shipping. As part of the maritime decarbonisation ecosystem, Wärtsilä delivers innovative solutions and expert guidance, and has a clear focus on enhancing efficiency and creating long-term value.