With growing pressure on ports to cut marine emissions, operators are developing ammonia-, hydrogen- and methanol-powered tugs
Tug owners are under increasing pressure to cut emissions in ports, leading to more owners deploying hybrid propulsion systems to lower fuel costs and gaseous emissions.
But in the long run, there is likely to be pressure to adopt fuels other than diesel for tug propulsion to cut greenhouse gas emissions. Which is why some tug operators and owners are testing zero carbon, or low carbon fuels such as hydrogen, ammonia and methanol.
One of the latest research and development (R&D) projects involving a tug using an alternative fuel has started in Japan. Shipowner NYK Line has teamed up with classification society ClassNK and IHI Power Systems to develop, construct and test one of the world’s first ammonia-powered tugboats.
They will use their experience in operating an LNG-fuelled tug, Sakigake, to introduce zero-carbon-emissions operations for towing and manoeuvring ships. In this flagship project, the companies will tackle technological development of the hull, engine and fuel supply system and develop safe navigation methods.
NYK Line will research and design the hull and fuel supply system and verify operations modes, based on its experience with 2015-built Sakigake.
IHI Power Systems will develop the engine and exhaust gas aftertreatment systems, while ClassNK will review and assess the safety aspects of this ammonia-powered tug.
After evaluating the practicality of the R&D results, the consortium will study the construction of the ammonia-fuelled tugboat.
The partners envision implementing ammonia as a marine fuel in tugboats that require a high output. They will study the possibility of commercialising marine equipment that uses ammonia for more vessels.
LNG-fuelled tugboat Sakigake is owned by NYK Line and is operated in Yokohama and Kawasaki ports under the navigation of Shin-Nippon Kaiyosha. Sakigake is equipped with a dual-fuel engine that can use either LNG or diesel, depending on conditions. The tugboat’s engine was constructed by IHI Power Systems (Niigata Power Systems at the time of construction).
When using LNG fuel, Sakigake becomes an eco-friendly tugboat with a 100% reduction in SOx, 80% NOx and 30% CO2 compared with heavy fuel oil.
Methanol and hydrogen
In Europe, owners and operators will be trialling methanol- and hydrogen-fuelled vessels in one of the continent’s busiest ports.
Port of Antwerp is investing in methanol-fuelled vessels as its first step towards reducing emissions. This is part of the port authority’s plan to encourage investment in alternative fuels and to operate environmentally friendly vessels. Its commitment to methanol involves retrofitting three vessels with dual-fuel engines.
Port of Antwerp technical manager Celine Audenaerdt said the authority expects to gain regulatory approval for the first of these retrofit projects before the end of this year.
She explained the port’s vision and strategy to become a pioneer in alternative fuels during the Alternative fuels for powering a tug: the selection conundrum webinar.
Port of Antwerp is the fifth-largest bunkering port worldwide. Therefore, it is in the authority’s interest to facilitate a transition to alternative fuels. It also has other roles, as a community builder, regulator, landlord and vessel operator, with fleets of tugs and dredgers.
Ms Audenaerdt said its investment in retrofitting vessels to use methanol is part of the EU-funded Fastwater project. “There will be three vessels retrofitted,” she said. This includes an inland/harbour tug, a pilot boat and coastguard vessel.
“We developed retrofit kits and will make business plans and train crew in this project,” said Ms Audenaerdt. These retrofit kits need to be scalable for other vessel and ship types.
Another aspect is commercialising medium-speed and high-speed methanol engines, then demonstrating reduced pollutant and CO2 emissions from the retrofitted vessels.
Ms Audenaerdt said other key elements are developing rules and regulations, including a methanol fuel standard, then demonstrating the complete supply chain from renewable methanol producers to ship bunkering.
Methanol is not the only option Port of Antwerp is interested in. It is investing in hybrid-electric propulsion patrol vessels being built in the Netherlands.
Plus, it is a partner in the Hydrotug project with CMB.Tech and Anglo Belgian Corp (ABC), to develop a hydrogen-fuelled harbour tug. CMB.Tech is developing Hydrotug as its largest hydrogen-fuelled vessel. “Hydrotug will be a 65-tonne bollard pull tug,” said project manager Roy Campe. “Hydrotug will have two 2-MW medium-speed engines and 400 kg of compressed hydrogen storage.”
As this tug will burn diesel in dual-fuel engines, it will have filters to remove particulates and selective catalytic reduction equipment for abatement of NOx. “We are using conventional technology that is affordable,” said Mr Campe. “With this project we will get the experience and training. Then we can look at other and bigger projects.”
Hydrotug is the first deployment of BeHydro, a new four-stroke, dual-fuel engine launched in September. Over the past three years, BeHydro has developed, produced and tested a prototype hydrogen-diesel engine with a capacity of 1 MW. Hydrotug will have two 2-MW prime movers.
BeHydro expects to scale up this technology to produce engines of up to 10 MW. It anticipates having capacity to produce 100 engines annually. There are plans to release a zero-emissions engine with spark ignition that will burn only hydrogen by Q2 2021. “There is no NOx, no hydrocarbons, no particulates and no CO2 emissions,” said ABC chief executive Tim Berckmoes. He explained this engine is “based on proven diesel engine technology, so is very safe, easy to operate, and the investment cost is quite low.”
Its hydrogen fuel engine will be available in the power range of 1 MW to 2.7 MW.
Besides the engines, BeHydro will provide the tanks for the compressed hydrogen, gas supply systems and engineering.
By injecting and burning compressed hydrogen, the medium-speed BeHydro dual-fuel engines will produce 85% less CO2 emissions than a standard diesel engine.
This is part of a greater strategy in Port of Antwerp. “We are investing in hybrid, hydrogen and methanol as developments become possible in these fuels,” said Ms Audenaerdt. “We are using lessons from LNG bunkering and overcoming the technology challenges,” she added.
Ms Audenaerdt expects these fuels to be used in other shipping sectors. “We want to be a multi-fuel port offering alternative fuels – we welcome pioneers,” she said.
Port of Antwerp is also open to other fuel options if these become viable. “We are keeping an eye on other alternatives such as ammonia, ethane and formic acid,” she explained.
There are several technical, commercial and legislative hurdles to providing and using alternative fuels. Ms Audenaerdt highlighted the main ones as supply chain, training, non-existing regulatory framework and finance. “The supply chain is a key hurdle. The challenge is to get alternative fuels where you want them,” she said.
Ms Audenaerdt thinks there will be some form of relief for regulatory challenges. “For the methanol tug we aim to get approval in 2020,” she said.
In June, Port of Antwerp ordered two reverse stern drive 2513 design tugs from Damen Shipyards for ship-handling in the port from 2021.
Inland hydrogen tugs
Hydrogen will also be used for powering inland waterway projects. One of the more ambitious projects is using hydrogen-powered tugboats on the Danube to transport hydrogen on 40 barges.
Netherlands-headquartered Chemgas Shipping intends to own a fleet of pusher tugs, powered by hydrogen. It has partnered with Austrian engineering group AVL and technology company TECO 2030 to install hydrogen fuel cells on river tugs.
This is part of the €5.85Bn (US$6.7Bn) Blue Danube hydrogen project that involves mass river transportation of hydrogen into central Europe.
Chemgas Shipping and AVL will use TECO 2030 hydrogen fuel cells for power and propulsion on pusher tugs involved in this transportation project.
TECO 2030 said “Testing is planned for the turn of the year 2021-2022, and we are looking to launch a new design as early as 2023.”
These pusher tugs will drive barges from Romania to Germany, transporting hydrogen produced in southeast Europe from renewable sources – solar and wind – of up to 80,000 tonnes per year.
It is anticipated this project will reduce Europe’s CO2 emissions by 3.2M tonnes per year.
In France, a consortium of organisations, involving ABB, Ballard Power Systems, Westcon Power and owners Norled/Compagnie Fluviale de Transport are developing a hydrogen-powered pusher tug to operate on the Rhone River.
In an EU-funded Flagships project, a pushboat is being designed by LMG Marin to be powered by two 200-kW fuel cells, connected to a compressed hydrogen storage tank.
There will be two tanks. When the first is empty, it could be removed and refilled with hydrogen as a second tank is used in its place.
In Germany, Behala is expected to begin operating hydrogen-powered Elektra pushboat this year. This 20-m vessel is being built by Hermann Barthel in Derben Germany, to transport goods between Hamburg and Berlin in 2021.
Its two Schottel-supplied rudderpropellers will be powered by fuel cells and rechargeable batteries. Elektra will transport Siemens turbines from the production centre in Berlin to the Port of Hamburg.
Other partners in this project include Ballard (fuel cells), Anleg (hydrogen tanks), EST-Floattech (batteries) and Schiffselektronik Rostock (electronics).
Methanol fuel cell production begins
Blue World Technologies has starting a limited production run in the first step towards commercialising fuel cell technology using methanol.
The Danish company expects initial production will lead to trials with vessel operators to lower emissions. It has worked to reduce production costs and time to commercialise the technology.
The experience gained from the limited production will be used to optimise production methods and processes as Blue World moves onto serial production of 2,000 to 5,000 units.
Containerised ESS developed for rapid recharging
Canada-headquartered Sterling PBES has introduced the CanPower microgrid box as an enclosed energy storage system (ESS) for vessels.
This ESS is in a container that can be installed and lifted off vessels, without the need for complex auxiliary systems. CanPower can be retrofitted to existing vessels or included in a newbuilding.
All power electronics, batteries, fire-fighting, ventilation, insulation and cooling systems are enclosed in an IP65, ISO-rated steel container. Its batteries can be charged in just six minutes, depending on available shore power using Sterling PBES’ C-Max connectors.
CanPower can be removed and replaced in minutes using a standard shore crane system. The system can then be charged onshore as another one is installed on the vessel.
Riviera is hosting the Smart Tug Operations Virtual Conference on 1 December. Use this link for more details, programme and to register