The development of ‘green’ vessel propulsion systems stands firmly fixed as one of the top five critical issues facing the maritime industry in 2024.
“Markets are beginning to accept that fossil fuels will be needed in the transition [to zero carbon fuels], while owners adopt operational measures such as vessel speed, maintenance, and route optimization as new technologies and designs, such as carbon capture, take effect,” according to Holland & Knight (H&K) in its January Maritime Outlook: 5 U. S. Maritime Issues to Watch in 2024 report.
The multinational business law firm further notes, U. S. ship operators face several serious “headwinds” blocking attempts to decarbonize, such as “operational requirements, limited available financial incentives, and lack of readily available, one-size-fits-all alternative fuel solutions.”
In other words, ship operators, engine builders, ship designers, and other maritime-related companies aren’t sure of the pathways they need to take to reach or support the end goal of net zero operations, and they are hesitant to invest in new vessels and equipment.
Congress and other bodies are plowing ahead with new legislation and regulations in an attempt to sort out the confusion.
New legislation recently put forward in Congress includes H.R. 6681 – the Renewable Fuel for Ocean-Going Vessels Act – a proposed amendment to the Clean Air Act, which would provide credits for the use of renewable vessel fuels.
Meanwhile, the recently passed Inflation Reduction Act (IRA), may prove to be a source of incentive funding and credits for shipowners, and other impacted groups to help them through the transition, although, as H&K cautions, the IRA “was not designed specifically for the maritime industry.”
Another significant regulatory issue is an upcoming update to the U.S. National Blueprint for Transportation Decarbonization, which was developed to support sustainable transportation by the U. S. Departments of Energy and Transportation, and several other federal agencies.
A Decarbonization Action Plan is expected to take shape in 2024, which, it is hoped, will provide guidance on alternate fuels and new technologies across all vessel types and classifications.
Green Shipping Corridors and the CII
The International Maritime Organization’s (IMO’s) has designated 2050 as the target date for complete decarbonization of the worldwide maritime industry.
The H&K report also notes that the U. S. Department of State will continue to work with foreign governments to develop Green Shipping Corridors, which are “maritime routes that showcase low- and zero-emission lifecycle fuels and technologies…in support of sector-wide decarbonization no later than 2050.”
According to U.K.-based Admiralty Maritime Data Solutions, Green Shipping Corridors are specified global shipping routes that “can provide crucial environmental benefits such as increased biodiversity and a cleaner marine environment, as well as economic savings from reduced running costs and shorter anchorage times. These benefits can be achieved by using technology and automation.”
Currently, more than 50 ‘Green Shipping Corridors’ have been proposed by government agencies and global maritime organizations around the world.
The year 2024, analysts predict, will also be an active one for environmental regulations both internationally and domestically.
For example, this is the first year that Carbon Intensity Indicator (CII) verification from the IMO will be required for ships, covering their operations in calendar year 2023.
The CII is a measure of a ship’s energy efficiency, which is counted in grams of CO2 emitted per cargo-carrying capacity and nautical mile. Under the regulation, ships receive an environmental rating of A (major superior), B (minor superior), C (moderate), D (minor inferior), or E (inferior performance level). The regulations will become increasingly strict until 2030.
Overseas experts tend to agree with U.S. analysts that regulations and laws will play a crucial role in pushing the development of alternative fuels and propulsion systems.
“The forthcoming transformation will be driven by regulation as the industry will not buy expensive fuels just for the sake of it,” says Oskar Levander, senior vice president of business concepts, for Kongsberg Maritime, the Norway-based ship designer and maritime systems developer.
He made his remarks in a recent article that recently appeared in The Full Picture, a company publication that focuses on new technologies and sustainability.
“For mainstream shipping such as container ships, I think the main options will be green ammonia, synthetic methane or bio or green methanol,” wrote Levander predicts, who believes that “multi-fuel” solutions will be the best option for operators of large bulk or container vessels.
The dual-fuel choice of LNG and diesel “has been around for a while and is now common in the industry. But we are now seeing customers specifying ammonia or methanol readiness for their vessels as well,” he said.
Mariner’s Report In
While looking ahead to new alternative fuel propulsion systems, there are many strategies that ship operators and designers can use to improve fuel efficiency and reduce emissions today.
D1MEBA, the Marine Engineers Blogger Association, has a quick guide to green shipping – Green Ships: Sustainable Practices in the Maritime Industry – with several such strategies posted on its high-profile blogging platform, which is written and maintained by professional mariners with years of engine room experience.
The guide, compiled by marine engineer Isaac Wells, notes that current steps to improve sustainability and decarbonization “that range from applying anti-fouling coatings to a ship’s hull to prevent barnacles or other organisms forming and increasing drag to slow-streaming, or sailing at slower speeds for major stretches of a route.”
Those steps, he said, “can save significant fuel and emissions, to installing or retrofitting equipment to improve the efficiency of shipboard power systems.”
Another environmental necessity, he wrote, “is effectively managing the treatment of ballast water to ensure that clean water is discharged to prevent the spread of invasive species.”
Even the breaking-up of scrapped vessels falls under the purview of “green shipping” with Wells stating that “traditional ship-breaking methods in many parts of the world can release hazardous materials and other pollutants and thus, the process must be managed with an eye to the safe and sustainable disposal of components.”
Retrofitting
Retrofitting existing vessels can deliver benefits to ship operators while they are waiting for a clearer transition path to materialize.
Kongsberg also designs and equips retrofits for existing vessels as part of its sustainability strategy.
The company is currently retrofitting several vessels with hybrid propulsion systems and other upgrades in order to reduce carbon emissions by more than 20 percent for passenger ferry operator Hurtigruten Norway,
Its recently retrofitted ferry, M/S Richard With, is already seeing a 23 percent reduction in its carbon emissions, the company said.
The vessel has been equipped with two hybrid shaft generators and employs two 1.120kWh lithium ion batteries and two new Bergen B33:45V engines for propulsion.
Meanwhile, a new company called Shipglide promises a 10 percent reduction in fuel consumption by employing its proprietary Air Lubrication Systems to reduce hull drag.
Employing a layer of “air lubrication” to help hulls glide easier, the system can be retrofitted to existing vessels.
According to the company, “Many energy saving devices (ESDs) aim to reduce drag and fuel consumption, including hull coatings, optimized hull design, propulsors, and propeller boss cap fins.”
Its air lubrication systems “offer up to 10 percent in energy savings, while other ESDs often achieve less than two percent,” it said.
The air lubrication systems, it states, “create a layer of air bubbles below the hull…and allow ships to operate with less drag. Reduced drag results in reduced pollution and reduced fuel consumption.”
New Hull Forms and Propulsion Systems
Craig Taylor, a spokesman for Kongsberg, points to another company project to design and equip a fleet of chemical tankers for a Swedish operator that employs advanced sustainability features throughout.
“The company, he said, “is embracing the fuel transition and [has] a big desire to adopt sustainable technologies. The first nine ships, ordered in three batches by Swedish owner Tarntank, are based on our super-efficient hull form, and feature progressive steps to improve efficiency, through the use of methanol fuel, batteries, and even wind-assisted propulsion on the final three.”
The ships, said Taylor, “will be highly efficient and will have an Energy Efficiency Design Index above 40 percent that’s well below the 2025 Phase 3 requirements.
This series, he adds, “has also been followed by a further order from Sirius Rederi AB, for two more vessels of a very similar design, without suction sails.”
Hydrogen Conversion
In another development for “greening” equipment, Mitsui Engineering & Shipbuilding recently claimed an important breakthrough in partially converting a MAN engine to operate on hydrogen.
In collaboration with Germany-based MAN Energy Solutions, the company reported that it has “achieved a world first with a successful hydrogen combustion operation of a large marine two-stroke test engine with a bore size of 50 cm located at its Tamano factory, aiming for the early launch of hydrogen-related businesses in [the] maritime industry.”
When announcing the new engine development, Mitsui stated that, “one of the four cylinders of the test engine 4S50ME-T – output 7 MW, rated speed 117 rpm, MEP = 2.10 MPa – was converted to hydrogen operation, based on the LNG-fired ME-GI engine design.
High-pressure hydrogen gas was provided from a storage facility equipped with liquid hydrogen tanks and compressors, that was completed late last year, according to Mitsui.
The coupling operation “was successfully conducted with this test engine at 100 percent load without any problems such as hydrogen leakage,” the Tokyo-based company said.
By collaborating, it added, Mitsui and MAN Energy Solutions “will acquire the technologies and know-how related to the storage, supply and utilization of hydrogen, which is a next-generation fuel, through the development of hydrogen fuel propulsion system technologies and hydrogen supply infrastructure-related technologies.” •