IMO Advances Certification Rules for Engines Using Ammonia and Hydrogen

The International Maritime Organization (IMO) is taking concrete steps to facilitate the adoption of alternative marine fuels, a critical move for the decarbonization of shipping. Draft amendments to the NOx Technical Code, agreed upon at the PPR 13 session, will enable the certification of marine engines running on fuels like hydrogen and ammonia.

Key Technical Specifications and Facts

The core development stemming from the PPR 13 session is the agreement on draft amendments to the NOx Technical Code. This code governs the standards for nitrogen oxide (NOx) emissions from marine diesel engines. The key technical update involves the addition of hydrogen- and oxygen-balance methods to the existing carbon-balance approach for emissions calculations.

Currently, the NOx Technical Code relies primarily on the carbon-balance method for assessing engine emissions. However, this method is not directly applicable to engines fueled by non-carbon fuels like hydrogen and ammonia. The inclusion of hydrogen- and oxygen-balance methods provides a framework for accurately measuring and regulating NOx emissions from engines operating on these alternative fuels. This is a vital step toward enabling their widespread adoption.

Furthermore, the PPR 13 session addressed other crucial environmental concerns. Discussions included the development of a “polar fuel” concept aimed at reducing black carbon emissions in the Arctic, and early considerations regarding the management of ammonia effluent from ammonia-fueled ships. New requirements for crude oil tankers to be fitted with pressure/vacuum valves to reduce volatile organic compound (VOC) emissions were also drafted.

Technical Analysis — Innovative Approach to Alternative Fuel Certification

The IMO’s decision to incorporate hydrogen- and oxygen-balance methods into the NOx Technical Code represents a significant technical advancement. By establishing a standardized methodology for evaluating NOx emissions from hydrogen and ammonia engines, the IMO removes a key barrier to their commercialization. This allows manufacturers to design and build these engines with the confidence that they can be certified and comply with international regulations.

The innovative aspect lies in adapting existing regulatory frameworks to accommodate fundamentally different fuel chemistries. The carbon-balance method, effective for traditional hydrocarbon fuels, becomes obsolete when carbon is not a primary component of the fuel. Hydrogen and ammonia combustion produce different emission profiles, requiring alternative measurement and calculation techniques.

The hydrogen- and oxygen-balance methods likely involve sophisticated analytical techniques to determine the concentrations of various emission products, including NOx, unburned hydrogen or ammonia, and other potential pollutants. These measurements are then used to calculate the overall NOx emissions based on the mass balance of hydrogen and oxygen in the combustion process.

Industry and Regulatory Context

The maritime industry is under increasing pressure to reduce its greenhouse gas (GHG) emissions. The IMO has set ambitious targets for decarbonization, aiming for a significant reduction in carbon intensity by 2030 and a pathway towards net-zero emissions by or around 2050. Achieving these goals requires a transition to alternative fuels, and hydrogen and ammonia are considered promising candidates.

However, the lack of clear regulatory frameworks for these fuels has hindered their adoption. The amendments to the NOx Technical Code address this issue by providing a pathway for engine certification. This is a crucial step in creating a level playing field for alternative fuels and encouraging investment in their development and deployment.

The IMO’s efforts are complemented by national and regional initiatives. For example, the European Union’s FuelEU Maritime regulation mandates a gradual reduction in the GHG intensity of energy used onboard ships calling at EU ports. This regulation further incentivizes the adoption of alternative fuels and technologies.

Why This Matters for the Hydrogen Shipping Sector

For the hydrogen shipping sector, the IMO’s decision is a major catalyst. It signals a clear commitment to supporting the use of hydrogen as a marine fuel. The ability to certify hydrogen-fueled engines is essential for building confidence among shipowners, operators, and investors. It allows them to demonstrate compliance with environmental regulations and access potential financial incentives.

This development also has implications for the design and construction of hydrogen-powered vessels. Shipbuilders can now integrate hydrogen engines into their designs with the assurance that these engines can be certified. This facilitates the development of innovative ship concepts that maximize the benefits of hydrogen fuel, such as reduced emissions and improved efficiency.

Furthermore, the amendments to the NOx Technical Code pave the way for the development of hydrogen bunkering infrastructure. As more hydrogen-fueled ships enter service, the demand for hydrogen fuel will increase. The availability of certified engines will encourage the development of bunkering facilities at ports around the world, creating a sustainable hydrogen supply chain for the maritime industry.

Challenges and Open Questions

While the IMO’s decision is a significant step forward, several challenges and open questions remain. One key issue is the management of ammonia effluent from ammonia-fueled ships. The PPR 13 session acknowledged the need for more data before policy decisions can be taken on this issue.

The potential environmental impacts of ammonia effluent, including its toxicity to marine life, need to be carefully assessed. Solutions for treating or minimizing ammonia effluent will be crucial for the widespread adoption of ammonia as a marine fuel.

Another challenge is the development of comprehensive safety standards for hydrogen and ammonia bunkering and handling. These fuels have different properties and risks compared to traditional fuels, requiring specific safety protocols and equipment. The IMO and other regulatory bodies need to develop clear and consistent safety standards to ensure the safe operation of hydrogen and ammonia-fueled ships.

Finally, the cost of hydrogen and ammonia production and distribution remains a barrier to their widespread adoption. Reducing the cost of these fuels will be essential for making them economically competitive with traditional fuels. This requires investments in renewable energy sources, hydrogen production technologies, and infrastructure development.

Sources

shipandbunker.com — https://shipandbunker.com/news/world/374237-imo-advances-certification-rules-for-engines-using-ammonia-and-hydrogen