Industry takes practical steps towards alternative fuels

New projects are developing and testing alternative fuels that will help the maritime industry decarbonise and reduce greenhouse gas (GHG) emissions

IMO has set goals to halve these gaseous emissions from the international shipping sector by 2050. This will require shipping to widely adopt fuels with lower, or zero, carbon content for the next generation of vessels.

Before the industry can commit to the huge levels of investment needed for new low- or zero-emission ships, the sector is testing the technology on tugs, workboats, patrol vessels and passenger ships. It is also using its experience in handling and bunkering LNG as a stepping stone to lower carbon alternatives.

PSA Marine is building up its experience of operating LNG-fuelled tugs with a pair of vessels operating and bunkering in Singapore. Its 2019-built harbour tugs PSA Aspen and PSA Oak have dual-fuel engines, supplied respectively by Niigata and Wärtsilä.

When these are burning gas, emissions of SOx, NOx and particulates are negligible, while there are significant reductions in GHG, according to PSA Marine senior manager for fleet engineering Jeffrey Sim.

“We have seen a 22% reduction in CO₂ and 15% lower noise levels for better crew comfort, compared with conventional diesel-fuelled tugs,” said Mr Sim during Riviera Maritime Media’s Alternative fuels for powering a tug: the selection conundrum webinar on 2 September.

Countering the positives from LNG use, PSA Marine has also faced challenges, including additional safety and manning for truck-to-tug bunkering.

“Bunkering takes three times longer than with a conventional diesel tug, so we need to book this up to seven days in advance,” said Mr Sim.

He said the operation needs additional crew deployment for monitoring bunkering, manning the bunker station and controls in the engineroom.

“The world is changing and that the ways we operate and conduct business need to change with it”

There are also additional safety protocols, such as quick connect/disconnect cryogenic couplings and hoses for fuel transfer, a water curtain and drip tray and nitrogen gas supply for purging.

Crew also need training to manage bunkering operations, dual-fuel engine maintenance and to maintain onboard LNG storage and handling systems.

This was covered by PSA Marine through classroom and onboard training, bunkering courses and hazard workshops.

During his presentation, Mr Sim shared PSA’s LNG triangle to explain the decisions and challenges involved in operating dual-fuel tugs.

Mr Sim said financial and regulatory support is important to help cover the additional capital costs for building a dual-fuel tug compared with a conventional diesel vessel.

PSA Aspen and PSA Oak have similar features in overall length, gross tonnage, LNG tank capacity, maximum speed and bollard pull.

Methanol trials

Alternative fuels currently in development include low carbon methanol, LPG and ethanol, and zero-carbon ammonia and hydrogen. One of Europe’s biggest ports and bunkering hubs is a pioneer in developing methanol- and hydrogen-fuelled vessels, and it is encouraging LNG bunkering.

Port of Antwerp is investing in methanol-fuelled vessels as its first steps to reducing emissions. This is part of the port authority’s plan to encourage investment in various 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 interests 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.

“Bunkering takes three times longer than with a conventional diesel tug”

Ms Audenaerdt said its investment in vessel retrofits to 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.

Another aspect is commercialising medium-speed and high-speed methanol engines, then demonstrating reduced pollutant and CO₂ emissions from these three 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.

It is also a partner in the Hydrotug project with CMB.Tech and Anglo Belgian Corp (ABC), to develop a hydrogen-fuelled harbour tug, and it can offer LNG bunkering to shipping sectors. 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. “It 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, bigger projects.”

CMB has already brought Hydroville, a small passenger vessel, into operation in Belgium. The company is also building Hydrobingo, a larger passenger shuttle in Japan along with Hydrocat, a hydrogen-fuelled crew transfer vessel for offshore windfarms.

“We are investing in hybrid, hydrogen, methanol as developments becomes 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 will 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, people training, the absence of an 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.

On training, Port of Antwerp has more than 300 people working on its tugs and dredgers. “They need to be trained on fuels and how to operate the technology,” she said. At least this challenge is within the tug operator’s own control. Its requirements for a regulatory framework lie elsewhere.

Ms Audenaerdt thinks there will be some form of relief for this challenge. “For the methanol tug we aim to get approval in 2020,” she said.

Tanker owner Hafnia plans to operate methanol-powered tankers for a production and export project in the US. It has invested in a US$10M joint venture with an unnamed partner in methanol production facility, Northwest Innovation Works (NWIW) in the port of Kalama in Washington state.

NWIW is developing a 3.6M tonnes per annum methanol production and export facility. This plant will load methanol on the equivalent of an MR product tanker every four days, for dedicated trade to Asia. To accommodate this, Hafnia will order new methanol-powered dual-fuel tankers tied to 19-year charters to transport one-third of the methanol volume produced by the plant.

Hafnia chief executive Mikael Skov said the initiative is part of the company’s strategy. “We recognise the world is changing, and that the ways we operate and conduct business need to change with it,” he said.

“While there is much uncertainty as to exactly what the future will look like, we are confident that the steps we are taking have Hafnia, our stakeholders and the industry moving in the right direction.” Mr Skov said.

Ammonia tug project

Ammonia is another alternative fuel that is gaining traction. The latest research project in this area involves a Japanese consortium – ClassNK, NYK Line and IHI Power Systems – looking 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. The companies will tackle the 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 operational modes, based on its experience with the 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 the 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 multiple tugboats that require 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 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 100% reduction in SOx, 80% NOx and 30% CO₂ compared with heavy fuel oil.