Thursday, June 01, 2023

 

Methanol Institute Publishes 1st Guide to Methanol as a Marine Fuel

The Methanol Institute
Tool to support decision-making on future fuel choices includes analysis and commentary on technical, commercial and operational aspects.

PUBLISHED MAY 31, 2023 9:14 AM BY THE MARITIME EXECUTIVE

 

[By: The Methanol Institute]

The Methanol Institute (MI) has published the first comprehensive guide to methanol as a marine fuel. As the shipping industry continues its transition towards net carbon neutral operations, owners are increasingly choosing methanol as a fuel that can help them progressively reduce emissions in line with regulatory targets.

‘MARINE METHANOL Future-Proof Shipping Fuel’ has been produced to help stakeholders across the industry access the information they need to support decision-making on which alternative fuel is right for their fleet.

Sections of the report address regulatory drivers, environmental performance, engines and fuel systems, bunkering, handling and safety characteristics, costs and pricing, availability and feedstocks for conventional and renewable product. Also included are case studies on first movers including AP Moller-Maersk, Waterfront Shipping, Proman Stena Bulk and the conversion of ropax ferry Stena Germanica.

The orderbook for methanol fuelled ships has grown rapidly with owners and operators specifying the fuel for use on ships from the largest containerships to small pilot boats. In between is the growing fleet of methanol carriers, bunker tankers, bulk carriers, heavylift vessels, cruiseships, ferries and superyachts.

Approved for use as fuel under the IMO’s IGF Code, the momentum for methanol as fuel has increased as studies, analysis and guidance - much of it supported by the Methanol Institute - has been published. This includes early guidance for bunkering operations developed with Lloyd’s Register and subsequent work with the ports of Shanghai, Singapore and Rotterdam. Propulsion systems include tried and tested two-stroke main engines, four stroke units, and fuel cells using methanol for conversion to hydrogen. Main engine manufacturers report considerable order backlogs and are developing ever larger, higher capacity units. Studies and pilots continue to prove the effectiveness of converting smaller main engines to methanol operations.

“Methanol has staked a significant claim to be among the serious fuel choices for vessel designers, owners and operators looking to make a start on their transition to sustainable operations,” said MI Chief Executive Officer Greg Dolan. “While there won’t be a single decarbonization solution, it is clear that methanol has advantages that combine to provide a pathway to lower carbon and ultimately carbon-neutral operations; This report provides a clear roadmap for this journey.”

“Shipowners have recognised that methanol provides them with huge flexibility in introducing a low-pollution, lower carbon fuel which is closest to a drop-in available in the market,” said MI Chief Operating Officer Chris Chatterton. “The decision by more and more leading shipping companies to adopt methanol as fuel signals that the industry recognises the need to start its transition to net carbon neutrality now; this publication can support their decision-making process.” To download the guide, please click here.

For more information, please visit www.methanol.org.

The products and services herein described in this press release are not endorsed by The Maritime Executive

 

South Africa Launches Inquiry Into Suspicious Russian Port Call

Lady R
Lady R at Simon Town, December 2022

PUBLISHED MAY 29, 2023 9:06 PM BY THE MARITIME EXECUTIVE

 

Following accusations of providing weapons and ammunition to Russia to aid Moscow’s war in Ukraine, South Africa’s top leadership has moved to defuse major fallout with the U.S. by appointing a panel to investigate the docking of a sanctioned Russian cargo ship at a naval base and establish whether any cargo was loaded.

A fortnight ago, U.S ambassador Reuben E. Brigety II accused South Africa of aiding Russia’s aggression in Ukraine after the sanctioned Lady R cargo ship docked at the country’s Simon’s Town naval base in December last year where it “uploaded weapons and ammunition."

Despite initially vehemently denying the accusations, South Africa President Cyril Ramaphosa has now appointed a three-member independent panel that will be headed by a retired judge to unearth the facts of the Russian vessel’s presence in the country in early December.

The investigation comes when the foreign ministers of the BRICS group, including Russia’s Sergey Lavrov, are meeting in South Africa to discuss pressing geopolitical issues, among them building a more influential alliance to counter the west.

While the U.S has called on its allies to condemn and isolate Russia over the Ukraine invasion, South Africa has largely leaned in favor of Moscow, despite projecting a neutral stance.

The investigation panel, which has six weeks to investigate the Lady R affair, will be mandated to establish the circumstances that led to the docking of the ship and the alleged loading of cargo and its subsequent departure from Simon’s Town in Western Cape. The panel will also be required to establish the persons who were aware of the ship’s arrival, and the nature of any cargo off-loaded or loaded, as well as the destination of the cargo.

“The President decided to establish the enquiry because of the seriousness of the allegations, the extent of public interest and the impact of this matter on South Africa’s international relations,” said the Presidency in a statement.

The panel will also evaluate whether all applicable laws were complied with during the port call. It will also include recommendations on actions to be taken against those responsible if it establishes that breaches occurred.

South Africa’s opposition party, the Democratic Alliance, has welcomed the appointment of the panel and presented some tough questions that it wants answered over the Lady R debacle.

In particular, the Alliance wants the panel to establish why the ship was allowed to avoid the official entry and exit points of Portnet ports, who gave permission for the ship to be escorted by two naval vessels, and whether the top defense and naval leadership was involved in the ship’s entry and exit. T

“We believe the investigation must reveal why the government did not respond in time to the advance warning by the U.S about the visit of the Lady R, although the ship was never supposed to dock at a South African port,” noted the Democratic Alliance in a statement.

The docking of Lady R in South Africa’s biggest navy base is threatening to cause a rift between the U.S and South Africa, a risk the investigation could help avert. The U.S has hinted at taking action against South Africa if it is found to have aided Russia’s war in Ukraine or helped Moscow evade sanctions, with options like sanctions and revoking trade privileges on the table.

Malaysia Detains Chinese Grab Dredger for War Grave Desecration

Chuan Hong 68 in operation (Hazz Zain)
Chuan Hong 68 in operation (Hazz Zain)

PUBLISHED MAY 29, 2023 10:27 PM BY THE MARITIME EXECUTIVE

 

A Chinese grab dredger notorious for vandalizing warship graveyards has been detained by Malaysian authorities after reports that the ship was dredging up pieces of the WWII warships HMS Prince of Wales and HMS Repulse. The two warships were bombed and sunk by aircraft of the Imperial Japanese Navy in 1941, leading to the loss of 842 men. It remains one of the worst disasters in British naval history.

The dredger Chuan Hong 68 was spotted last week at the wreck site, and a patrol boat from the Malaysian Maritime Enforcement Agency (MMEA) transited out to inspect it on Monday. The MMEA employed the local practice of detaining the ship for unpermitted anchoring. In this case, more than anchoring was at stake: On board, the inspectors found rusting artillery shells and other scrap on the ship. The shells appeared to be similar to other unexploded ordnance discovered at a scrap yard in Tanjung Belungkor on May 19, where a barge associated with the Chuan Hong 68's operation had been spotted.

The Chuan Hong's connection with wreck site robbing is under investigation. The penalty for the crewmembers could be as much as two years in prison if convicted, according to the New Straits Times.

Professional diver Hazz Zain first flagged the illicit commercial operation for the authorities earlier this month, drawing on information from local fisherment. Videos and pictures circulating on social media appeared to confirm their account. 

“We are distressed and concerned at the apparent vandalism for personal profit of HMS Prince of Wales and HMS Repulse. They are designated war graves. We are upset at the loss of naval heritage and the impact this has on the understanding of our Royal Navy history,” said Professor Dominic Tweddle, National Museum of the Royal Navy Director General.

Chuan Hong 68 had returned to the warship graveyard after a six-year lull. The Chinese grab dredger had gained notoriety over 2015-2018 for vandalizing sunken warships. In 2017, the dredger was responsible for illegally scavenging the wrecks of the pre-WWII Japanese destroyer Sagiri, plus the passenger vessels Hiyoshi Maru and Katori Maru, the steamship Igara and the tanker Seven Skies. 

“What we need is a management strategy for the underwater naval heritage so that we can better protect or commemorate these ships. That may include targeted retrieval of objects,” said Tweddle.

ENDING ECOCIDE

Salvage of oil tanker stranded off Yemen can begin: UN


By AFP
Published May 30, 2023

Crew from the support vessel Ndeavor spy the abandoned oil tanker FSO Safer near the coast of Yemen in a handout photo from Dutch company Boskalis 
— © KCNA VIA KNS/AFP/File STR

The United Nations said Tuesday it is ready to start salvage work on an oil tanker stranded off Yemen’s coast with more than one million barrels of crude that pose an acute risk to the environment.

“We’re very happy to be on site where we can start the work,” David Gressly, the UN coordinator for Yemen, said by videoconference from aboard a support vessel that has arrived at the stricken ship, the FSO Safer.

In an unprecedented salvage plan, the UN has purchased a super-tanker to remove the oil from the vessel in the Red Sea. The actual pumping will start in about 10 days to two weeks, said Gressly.

The 47-year-old Safer has not been serviced since Yemen’s civil war broke out in 2015 and it was left abandoned off the rebel-held port of Hodeida, a critical gateway for shipments into a country heavily dependent on foreign aid.

Experts say the ship is at risk of breaking apart, exploding or catching fire.

The Safer’s 1.1 million barrels are four times as much oil as that which spilled in the 1989 Exxon Valdez disaster off Alaska, one of the world’s worst ecological catastrophes, according to the UN.

The salvage operation, which will cost an estimated more than $140 million, has been assigned to a company called SMIT Salvage. It will pump the oil from the Safer to the now UN-owned ship called Nautica, and then tow away the empty tanker.

That’s much cheaper than the costs estimated to take care of a potentially catastrophic oil spill, which would take $20 billion to clean up.

But the UN says it is still $29 million dollars short on the sprawling project.

A SMIT support vessel called the Ndeavor arrived Tuesday at the site loaded with equipment. It will begin preparatory work on Wednesday.

“With the arrival of the Ndeavor next to the FSO in the Red Sea, we truly have reached a critical milestone,” said Achim Steiner, head of the UN Development Programme, which is in charge of the salvage operation.

“If all goes according to plan, somewhere in late June, early July, we might be in a position to say that that critical phase of the ship-to-ship transfer could be completed,” Steiner said.

Video: UN-Backed Salvage Team Arrives at FSO Safer off Yemen

FSO salvage operation begins
Salvage experts arrived at the FSO Safer off Yemen and are beginning with a visual inspection of the decaying vessel (UN photo)

PUBLISHED MAY 30, 2023 12:26 PM BY THE MARITIME EXECUTIVE

 

The team for the UN-backed salvage effort of the decaying offshore oil storage tanker FSO Safer (406,000 dwt) arrived in Yemen today, May 30, to begin the operation that plans to transfer the more than one million barrels of crude oil from the decaying tanker. Boskalis and the team from SMIT reported that they departed Djibouti along with UN representatives on May 29 to begin an operation that has been estimated will take more than seven weeks.

“After two years of political groundwork, fundraising, and UNDP project development, the operation on the water is set to begin!,” David Gressly, United Nations Resident and Humanitarian Coordinator in Yemen Tweeted today. After years of working to reach the agreements necessary for the operation, Gressly was aboard the Boskalis vessel Ndeavor as it arrived at the FSO Safer.

The UN has been leading the difficult negotiations originally proposing to survey the vessel and oversee repairs to the rebels which control that region of Yemen. The earlier agreements to oversee the maintenance and repairs of the vessel which was built in 1976 failed and the UN later reported that it had been determined that the FSO Safer was beyond repair and at imminent risk of leaking, sinking, or possibly exploding because its tanks have not been properly vented in years. Only a skeleton crew with limited resources has been aboard the tanker moored about 4.8 nautical miles off the coast of Yemen.

 

 

The Ndeavor had recently been in Djibouti after passing through the Suez Canal. Joining in the international contributions, Egypt gave the vessel free passage in support of the effort. While in Djibouti, final supplies and a team of approximately 40 salvage experts and support staff boarded the vessel.

The plan calls for the team to immediately begin a visual inspection of the FSO Safer while also taking measurements regarding the level of toxic gas. The ventilation system has reportedly not been operational since 2017. The salvage team will inspect the pumps and engine room, the status of the mooring arrangement, and assess the condition of the estimated 1.4 million barrels of light crude as well as the cargo lines, inert gas lines, valves, and manifolds.

The team is also carrying a portable inert gas generator which they plan to use to begin to stabilize the tanks on the FSO Safer. They expect it will take two weeks during this first phase of the operation and only then will the tanker purchased from Euronav arrive in Yemen. The Nautica (307,000 dwt) is currently waiting in Djibouti.

 

UN supplied video shows the condition of the vessel as the team arrived today in Yemen

 

The actual transfer of the oil is expected to take 19 days between the two ships. During the final phase, which will require an additional 17 days, the salvage team will use a mobile spray tank cleaning machine. The residuals and dirty water will also be transferred to the Nautica.

Under the UN plan, the FSO Safer will be sold for green recycling. The UN is continuing the fundraising efforts to pay for the operation, noting that the oil belongs to rebels and can not be used to pay the costs of the transfer. 


Teekay Tanker Carries Out Back-to-Back Rescues in Central Med

Teekay
Image courtesy Teekay

PUBLISHED MAY 30, 2023 8:28 PM BY THE MARITIME EXECUTIVE

 

Earlier this month, a Teekay tanker conducted two back-to-back migrant rescues in the Mediterranean, then transited to an Italian port - a sequence which NGO rescue vessels are not permitted to follow. 

On May 8, the tanker Copper Spirit was under way westbound in the Mediterranean, bound for Italy. The ship received instructions from the Italian MRCC to divert and assist a boat in distress. 

In the dark of night, Copper Spirit arrived on scene, and the crew rescued all 35 people aboard the craft. 

Copper Spirit then received instruction to proceed north and rescue a second vessel in distress. She successfully rescued the occupants, then headed northwards to Catania with 107 survivors on board. She arrived a few miles off the port on May 9 and departed without incident, bound for the refinery at Milazzo.  

"Although it is part of international law, saving lives at sea is also a moral obligation and a strong personal belief of all seafarers across the globe," said Teekay in a statement. "We are truly glad to have contributed to the safety of 107 individuals. After all, it is our duty."

Legal challenges for back-to-back rescues

NGO rescue vessels may face fines or detention in Italy for performing the same series of actions. Italian law prohibits migrant rescue ships from making two or more rescues in the same voyage.

A new decree law on rescue-vessel operation was created by the right-wing government of Prime Minister Giorgia Meloni earlier this year. It requires rescue vessels to head to port immediately after each evolution, foregoing additional rescues even if the ship is in the vicinity of people in distress. If a rescue vessel is found to be in violation of this law, the master may be subject to a fine of more than $50,000, and the ship can be detained for up to two months. 

In the past, NGO SAR vessels remained in the transit zone for several days in order to carry out multiple rescue operations. As a practical matter, this has changed. "As soon as we finish the first rescue, we are given a port for disembarkation and told to sail to it at maximum speed without stopping again," explained Alessandro Porro, president of rescue organization SOS Méditerranée, in an interview in March. 

The law has been condemned by the UN, which has expressed concern that it will hinder the provision of life-saving assistance by SAR organizations in the central Mediterranean, resulting in more deaths at sea.

Charity vessel rescues almost 600 migrants off Italy

The New Arab Staff & Agencies
28 May, 2023

Charity Doctors without Borders (MSF) rescue almost 600 people off the coast of Sicily.


The Geo Barents had been conducting training activities when it was called in to undertake the rescue [Getty]

A vessel operated by the charity Doctors without Borders (MSF) rescued nearly 600 migrants sailing on an overcrowded boat which was in distress off the island of Sicily on Saturday, the group said on Twitter.

"After three hours of operation, the 599 survivors, including women and children, are now safely aboard... and being cared for by the medical team," MSF tweeted, saying its vessel the Geo Barents had been conducting training activities when it was called in to undertake the rescue.
The migrants will be disembarked in the southern port of Bari, as assigned by the Italian authorities, MSF said, adding it would take around 40 hours to reach the port.

Charities have criticised the Italian administration of Giorgia Meloni, which takes a tough stance against illegal immigration, saying it often assigns ports too far away from the areas where rescues take place.

















More than 47,000 migrant landings have been recorded in Italy so far this year, up from around 18,000 in the same period of 2022, interior ministry data show.

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https://greattransition.org/images/Hardt-Empire-Multitude.pdf

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Crowley Invests in Mobile Floating Dry Dock for Use with Floating Wind

mobile floating dry dock
Crowley and Tugdock will explore opportunities with the emerging floating offshore wind applications (Crowley)

PUBLISHED MAY 31, 2023 5:12 PM BY THE MARITIME EXECUTIVE

 

Crowley is investing in a UK-based startup, Tugdock, which is developing what is billed as the world's first road-transportable floating dry dock. The company plan to explore the potential use of the platforms especially to support the developing floating offshore wind applications in California and elsewhere in the U.S. It is the latest development of the U.S. maritime logistics company which has been moving to expand its role in the wind industry.

Found in 2017, Tugdock uses a patented marine buoyancy bag technology and a modular form that allows for the transport and assembly of floating dry docks that are delivered by road and assembled in port.  The technology allows them to offer dimensions far wider than most of the world’s existing dry docks, which they note were not designed for the news of the floating wind industry. They report the submersible platforms can operate in as little as 5 meters (approximately 16 feet) draft, enabling a more efficient construction and the air lift bag design provides a large lifting capacity. Once assembled, the platform can then be towed to deeper water for the launching of the turbines. It can be provided either as a purpose-built permanent or temporary pre-assembly solution.

"The cost and time constraints associated with port infrastructure developments and submersible barge suitability are major bottlenecks holding back the growth of the floating offshore wind sector," said Lucas Lowe-Houghton, Director of Strategy and Growth at Tugdock "Our TSP technology helps overcome these issues, providing a ready-to-go solution that does not require planning or environmental permissions.”

According to the companies, the technology for the portable, submersible platform, was developed to be launched in ports that lack sufficient water depth. It can help ports that lack the assembly space required to build and loadout the massive floating substructures required to support offshore wind turbines. They highlight the potential opportunities in locations, such as the U.S. West Coast, where depth and conventional dry docks may be ill-suited for the logistics required.

The Tugdock product line comes in a range of deck sizes from 12m x 12m up to 120m x 120m with a total lift capacity of up to 35,000 tonnes. The company reports the system can lift vessels and other floating structures clear of the water at a fraction of the cost of standard dry docks.

"This important investment and collaboration with Tugdock strategically complement our vision and market-leading logistics capabilities to support wind energy development from beginning to end," said Bob Karl, senior vice president and general manager, of Crowley Wind Services.

Crowley Wind Services is developing and planning wind terminals in California, Louisiana, and Massachusetts. At the California Port of Humboldt Bay, Crowley is progressing on an agreement to build and operate a terminal for manufacturing, installation, and operation of offshore wind floating platforms. They are planning for the use of large heavy cargo vessels and to provide crewing and marshaling services for the Pacific waters recently approved for leases for wind energy. 

Humboldt and other West Coast installations they note will rely upon floating offshore wind turbines due to the water depths and topography of the continental shelf. Globally they highlight that about 80 percent of the world's offshore wind power potential lies in waters deeper than 60 meters, according to the Global Wind Energy Council, which means that development will be contingent on the development of floating wind applications.


BOEM Finds No Environmental Impacts for Gulf of Mexico Wind Leasing

Gulf of Mexico wind farms
BOEM cleared the next step as it moves toward the Gulf of Mexico's fitst wind lease auction

PUBLISHED MAY 30, 2023 5:26 PM BY THE MARITIME EXECUTIVE

The Bureau of Ocean Energy Management (BOEM) issued a finding today that it believes there would be no significant impacts to environmental resources in the Gulf of Mexico if its proceeds with the proposed offshore wind leasing efforts in the Gulf. The bureau in October 2022 defined two initial target areas off Texas and Louisiana that would become the first wind lease sites in the area as it works to expand the country’s renewable energy supply.

The U.S. has developed a well-defined process of steps toward the leasing of offshore sites. BOEM in the latest development in the process, and preparing for the eventual auctions, today issued a final environmental assessment (EA). The process reviewed the potential impacts of offshore wind leasing on the U.S. Outer Continental Shelf in the Gulf of Mexico and used the analysis to determine potential issues with the selected sites.

“The completion of our environmental review is an important step forward to advance clean energy development in a responsible manner while promoting economic vitality and well-paying jobs in the Gulf of Mexico region,” said BOEM Director Liz Klein. “We will continue to work closely with our task force members, ocean users, and others to ensure that any development in the region is done responsibly and in a way that avoids, reduces, or mitigates potential impacts to ocean users and the marine environment.”

The findings for today’s announcement were based on the work of the Gulf of Mexico Intergovernmental Renewable Energy Task Force, a collaboration between, Federal, state, tribal, and local government agencies. It sought to use available science and indigenous knowledge to minimize conflicts between ocean uses. BOEM reports will continue to meet with the task force as the process moves forward.

The initial call area which comprises 30 million areas was announced in November 2021 and a year later BOEM announced the first two Wind Energy Areas offshore Texas and Louisiana that total about 682,000 acres. According to the bureau, the sites were selected as they represent offshore areas that appear to be the most suitable for wind energy development.

The environmental analysis was prepared for the entire 30-million-acre Call Area to allow greater flexibility for the possible identification of additional WEAs and to provide NEPA coverage in the event that non-competitive and research leases were proposed in the call area. The analysis considered potential environmental consequences of site characterization activities (i.e., biological, archeological, geological, and geophysical surveys and core samples) and site assessment activities (i.e., installation of meteorological buoys) associated with the possibility of issuing wind energy leases in the Gulf of Mexico. 

BOEM announced on February 22, 2023, its proposal for the first offshore wind lease sale in the Gulf of Mexico. If BOEM decides to proceed with the sale, the bureau will publish a Final Sale Notice at least 30 days ahead of the sale. It is widely anticipated that they will proceed with the sale in the coming months.

For any proposed offshore wind projects, BOEM will also develop Environmental Impact Statements to analyze the specific environmental consequences of the projects before deciding whether to approve them. The environmental statements would be prepared in consultation with appropriate government agencies and informed by input provided by key stakeholders, tribes, ocean users, and the public.


Why We Need Better Anchoring Systems for Floating Offshore Wind

Without more investment in anchor technology to streamline installation, the potential of floating wind to help the energy transition will be greatly reduced.

Equinor Hywind Tampen
Hywind Tampen wind farm, Norway. Karoline Rivero Bernacki/Equinor, CC BY-NC-ND

PUBLISHED MAY 29, 2023 7:17 PM BY THE CONVERSATION

 

[By Benjamin Cerfontaine and Susan Gourvenec]

Growing demand for cleaner energy sources means offshore wind farms are being built all over the world. More than 5,000 turbines must be installed each year until 2050 to limit global warming to 1.5?.

But in certain regions, like California, it is difficult to build wind turbines directly on the seafloor due to the steep drop-off of the continental shelf.

Even in areas with shallow coastal waters, such as the North Sea, congestion from shipping lanes, fishing activities, marine protected areas, tourism and existing energy infrastructure all impede new turbine construction.

So it’s hardly surprising that many of these new turbines will have to be located in deeper waters further out to sea.

Floating wind turbines are emerging as a promising solution. But turbines are also getting bigger at a rapid rate – allowing electricity to be produced at a lower cost.

The blades of Hywind Scotland, the world’s first commercial floating wind farm, tower 175 metres above the sea surface – the same height as the London skyscraper known as The Gherkin.

This represents a huge technical challenge. Located in deep waters, these large floating structures must withstand the relentless push and pull of the ocean while maintaining stability to ensure ongoing energy generation.

So, how do these colossal structures remain in place?

The four types of floating wind farm platform. Acteon, CC BY-NC-ND

The floating wind turbine

The mast of a floating wind turbine is connected to a platform, which is designed to provide stability. Several different types of floating platform exist, each with the dimensions of a football pitch.

Beneath the water, mooring lines keep the turbine stable and prevent it from drifting away. Mooring lines can be either very large steel chains or synthetic ropes. Each of the three steel chains used for Hywind Scotland, for example, are approximately 900 metres long and weigh 400 tonnes.

The mooring lines are attached to the seabed with a ground anchor. Most people will be familiar with anchoring a boat or securing the guy ropes of a tent with pegs.

In both cases, the anchor (or peg) is embedded into the ground, making it harder for the anchor to become dislodged as the weight and strength of the ground has to be overcome to pull the anchor out. The anchors used for floating wind turbines are based on the same principle, but at a far greater scale.

Three main types of anchor are used to fix the floating platform to the seabed, each with unique characteristics.

Drag anchors are similar to traditional boat anchors, but can have a 6 metre wingspan and weigh up to 50 tonnes. They are dragged into the seabed by an installation vessel and embed themselves into the ground until the required holding resistance is achieved.

Pile anchors are like very large (up to 60 metres in length) but hollow nails. These anchors are hammered into the ground using an extremely heavy hammer. If the turbine is being installed above very hard soils or a rocky seabed, then a hole can be drilled to facilitate the pile installation.

Suction pile anchors are also hollow cylindrical tubes, but a sealed top cap creates suction pressure when water is pumped from inside of the pile. This forces the pile into the seabed without the need for hammering (an effect similar to the use of a plunger to unclog a drain). This is the type of anchor used to secure Hywind Scotland.

The mooring chain for a floating wind turbine at Polarbase, Hammerfest, Norway. Øyvind Gravås and Even Kleppa/Equinor, CC BY-NC-ND

Choosing the right anchor

Floating wind farms are being planned for areas such as the Celtic Sea and coastal waters west of France. However, the presence of hard rock seabeds in both areas means drag anchors will be difficult to use.

Even in dense sand, a drag anchor may only partly enter the seabed, creating inadequate support for the largest turbines. Drilled piles are the best way to anchor floating turbines to hard rock, so in this case, a driven pile might be the only option.

But driving these piles into the ground generates significant underwater noise that can be harmful for marine species. Research has also found that the movement behaviour of Atlantic cod subtly changed in response to pile driving in the North Sea.

Even small changes in movement behavior could affect individual growth and reproduction rates, potentially influencing the growth rate of entire populations.

Several techniques have now been devised to reduce noise. This includes air bubble curtains to limit the ecological impact of floating wind farms. But these techniques may result in additional costs that could make pile anchors too expensive.

The world needs a lot more wind turbines, and technology now allows installation further out to sea. But, as identified in our recent review paper, these environmental and technical challenges for anchoring the structures in place must be addressed.

Without more investment in anchor technology to streamline installation, improve anchor performance and limit damage to the natural world, the potential of floating wind to help the energy transition will be greatly reduced.

Benjamin Cerfontaine is a Lecturer in Geotechnical Engineering, University of Southampton.

Susan Gourvenec is the Royal Academy of Engineering Chair in Emerging Technologies - Intelligent & Resilient Ocean Engineering, University of Southampton.

This article appears courtesy of The Conversation and can be found in its original form here

The Conversation

The opinions expressed herein are the author's and not necessarily those of The Maritime Executive.