The build-up of marine life on ships’ hulls, known as biofouling, is an age-old problem for ship operators and the shipping industry. Severe underwater biofouling slows the affected ship and can increase its fuel consumption by as much as 40%, boosting already high CO₂ emissions.
And biofouling doesn’t just slow down ships. The accumulation of marine life may cause the spread of invasive aquatic species in environments they’re transported to, affecting biodiversity, ecosystem health and the livelihoods of coastal communities across the globe. It’s something that regulators, ship operators, port authorities and conservation bodies are increasingly concerned about.
At the recent Nor-Shipping trade fair in Oslo, the environmental NGO Bellona Foundation launched the Clean Hull Initiative (CHI) to address the biofouling issue. The launch event was opened by Bellona’s project manager Runa Skarbø, who explained the background and drivers for the work.
“The CHI is a collaborative project initiated by the Bellona Foundation. It brings together a growing number of stakeholders in both the private and public sectors and aims to develop an industry-wide recognised and accepted standard for proactive hull cleaning which currently does not exist. We believe the standard is an important means to establish proactive cleaning as part of the biofouling management toolbox and will also drive innovation and the market for commercial proactive hull cleaning solutions.”
Major threat to the world’s oceans
Frederic Hauge, founder of the Bellona Foundation followed by stating in his keynote speech, “Biofouling is recognised as one of the greatest threats to the world’s oceans. Not only does biofouling serve as vector for the spread of aquatic invasive species it also increases hull resistance and decreases the propeller efficiency, leading to higher fuel consumption and increased emissions to air from ships.”
Hauge went on to emphasise the scale of problem, “By increasing frictional drag, it is estimated to account for 9% of the global shipping fleet’s fuel consumption every year. That equates to roughly 80 million tons of excess CO₂ emissions and USD 16 billion in extra fuel costs, based on today’s high fuel prices. Biofouling then is a big environmental problem and is costing the industry a lot of money.
“So, we want to work together with the industry and regulators to solve the environmental issues on a large scale, and the CHI is a perfect example of an ideal Bellona project. Together we will seek to sort out the regulatory barriers currently in the way of solving the biofouling issue. Also, we want to reduce barriers for the further uptake of emerging proactive hull cleaning technology as a preventative tool,” added Hauge.
There are of course other collaborations and initiatives that seek to tackle the biofouling issue, but Skarbø points out the CHI is unique in the sense that it is addressing proactive cleaning issues. She says regulatory inconsistencies worldwide create a major barrier to ship operators wanting to manage biofouling proactively, and for in-water cleaning (IWC) providers operating in multiple locations. Compounded by the absence of any international regulation or standard for hull cleaning, today there is no international regulating body for ports and anchorages where IWC takes place. Local biofouling and/or IWC management guidelines vary hugely, if they exist at all.
Spotlight on biofouling management issues
The launch event also shed more light on biofouling management issues and opportunities, the regulatory landscape and discussions on the importance safe proactive hull cleaning practices.
Angelika Brink, senior surface scientist at Jotun, gave the first presentation which covered the difference in extent of biofouling based on predictions and computer modelling and perception of actual biofouling. She said that while the models may appear to overestimate the amount and impact of biofouling it is likely that the opposite is true, and the impact of biofouling really is much higher than even the predictions.
Showing a graph detailing Glofouling’s study of impact of biofouling on emissions she indicated a point on it and said many would feel a 55% increase in GHG caused by just 1% biofouling coverage is impossibly high. Brink went on to cover the difficulties in quantifying fouling coverage based on observation particularly when different types of fouling were present. Some theories and tests have shown that it is not always the extend of coverage but the type of coverage that matters and a single large barnacle can have more impact on performance than many smaller ones.
She concluded that actual data collected in future would be improved by better correction for environmental factors, better understanding and estimation of coverage and types of fouling and more knowledge of surface effect interaction.
Revision of IMO biofouling guidelines
Next up was Sveinung Oftedahl, specialist director in the Norwegian Ministry of climate and environment, who gave an update on the revision of the IMO biofouling guidelines and the importance of hull cleaning. “The revision of the guidelines is currently being undertaken by a dedicated sub-committee and the work is progressing well, with completion targeted next year,” said Oftedahl.
He elaborated on the work tasks, while acknowledging the key goal is to increase uptake and effectiveness of the guidelines. “The intention is to make the guidelines clearer and less general meaning ‘specific recommendations on what to do, how to do it, when to do to it’ as well as include user-specific guidance and allocate clearly the responsibilities of various stakeholders. Moreover, the guidelines are to reflect chronological sequence from ship design to end of service life,” said Oftedahl.
In his concluding remarks, Oftedahl said, “Recommendations for safe biofouling management practices to prevent the spreading of invasive species will be a key issue in the work going forward at the IMO and it will be partly based on previous experience with, for example, the standard in the Ballast Water Management Convention. Certainly, the IMO will continue to develop relevant standards for shipping.”
Optimising hull conditions makes sense
Roger Strevens, vice president, global sustainability at Wallenius Wilhelmsen, gave a presentation titled ‘the benefits of good biofouling management practice – a ship owner’s perspective’. He said optimising hull conditions across the fleet of ships can result in significant savings, both in terms of reduced fuel costs and corresponding emissions so efforts to keep the hulls clean makes sense. “Our experience is the cleaner the ship, the greater the financial incentive which, in turn, creates a win-win situation for both the environment and business.”
He went on to emphasise “proactivity is prudence but there are operational complexities” and referred to what he called a “patchwork of national and local regulations.” This he believes “only increases the regulatory burden on many companies who may then be disincentivised to pursue efficiency efforts. There is a need for a level playing field, goal-based regulations and standards that encourage more take up of technologies and best practices, also when it comes to biofouling management.”
There then followed a panel discussion titled “safe proactive hull cleaning practices” moderated by Strevens. He was joined on stage by Claus Winter Graugaard, head of onboard vessel solutions at the Maersk Mc-Kinney Møller Centre for Zero Carbon Shipping, and Stein Kjølberg, global category director hull performance at Jotun. Dr Mario Tamburri from the University of Maryland Centre for Environmental Sciences and Luc van Espen, technical manager environment, Port of Antwerp joined the discussion via video.
Commenting on how the CHI fits with the broader decarbonisation work that the centre is focusing on Graugaard said while future fuels development clearly will play a central role in the push towards zero emissions, energy efficiency measures also have the potential to be an instrumental ally for ship operators in their decarbonisation journey.
Need to implement best practices
“The shipping industry faces a huge challenge as it works to meet the net zero 2050 goals. To do this, it must accelerate change and while much of the work centres on future fuel developments, it’s also important to take into consideration operational energy efficiency measures,” said Claus and added, “There are technologies and best practices that are proven and available like those used to achieve optimal hull fouling management. These can make a significant impact on the transition and also for individual operators who are seeking ways to improve hull performance, reduce fuel consumption and lower emissions. But there is also a need to educate the broader industry and implement the best practices and that’s why we support the CHI together with other industry stakeholders.”
When asked how CHI will play into the IMO’s forthcoming Carbon Intensity Indicators (CII) regulation Kjølberg said taking a proactive approach to biofouling management can help operators meet the increasing performance demands and regulatory requirements, including the CII of ships.
“As an operational index, the CII will have an impact on how ships are operated and we believe it will enable shipping to help reach the IMO’s goals,” but warned “At the same, it’s a challenge for ship operators because the CII measures revolve around the ship’s usage and impact the CII rating. So, it’s very important that the operators take action now so that they follow the CII trajectory. If they don’t they may end with a lot of issues.”
With potential new regulation on biofouling also on the agenda, Kjølberg believes improving hull performance addresses both the species transfer and decarbonisation issues. “Energy efficiency and carbon emissions are very much linked to fouling growth on ship’s hulls. So, keeping them clean is certainly the way forward, and this is where developments in high quality antifoulings, performance monitoring and proactive hull cleaning can make all the difference,” argued Kjølberg.
Holistic approach key
Asked about the technical readiness of proactive cleaning solutions, Dr Tamburri said, “It’s early days but development is underway, and some are showing a lot of promise. I think there’s a great chance of success and proactive cleaning, despite being a relatively new development, can form a very important part of the overall holistic approach to optimal biofouling management and vessel performance.”
Dr Tamburri also emphasised the need for “standards and best practices that can be implemented in an effective way and help solve the biofouling issue safely and properly.” Expanding on the words safely and properly he said, “It’s important that the cleaning is done in an effective manner so that it minimises fouling, increases vessel efficiencies and, at the same time, doesn’t damage the antifouling coating or the environment where the cleaning takes place. Ultimately, the real success of all this is dependent on enabling safe and effective proactive cleaning practices that facilitate the means to increase fuel efficiency while decreasing pollutants and biosecurity risk.”
Luc van Espen also stressed the importance of safety and a standardised approach to cleaning in ports. “Biological safety is of the utmost importance to us because as a port authority we prefer ships arriving with a clean hull to prevent the introduction of aquatic invasive species. Also, safety from an operational point of view is important, for example, when undertaking diving operations to clean the ship hull.”
Espen said he was in “favour of standardised cleaning approach because it’s not feasible to use different approaches in different ports” and said a joint policy on underwater hull and propeller cleaning in the Flemish ports has been launched by partner ports in the region. The uniform framework ensures that the market players are assessed in an equal manner, with equal procedures and acceptance criteria. “We are hoping for an international standardised approach because it will bring both environmental and commercial benefits,” he added.
The panellists agreed the economic and environmental impact of fouling, combined with the stringent regulations, are likely to lead to an increased focus on hull performance and a take-up on proactive measures and best practices as part of good biofouling management.
Low hanging fruit
In his closing remarks Morten Fon, president and ceo of Jotun, emphasised the importance of clean hull efficiency in achieving sustainable operations. “There is a lot of talk about the future fuels and the role they will play in shipping’s low-carbon future, but it is also important to focus on the low hanging fruit. Hull performance, and the hardware that keeps them clean, will continue to be a critical driver of efficiency gains for ships. There is however a need for an industry-wide standard and Jotun fully supports the Bellona initiative to define and implement a new ISO standard for proactive cleaning.”
Fon also praised the commitment of Bellona and the companies that have joined the CHI alliance and taken the lead towards the achievement of its objectives. “This is a joint effort to tackle the global biofouling issue and its negative impact for both commercial shipping and the environment. By working together, sharing insights and expertise, the CHI stakeholder members can help solve the biofouling issue on a large scale.”
The CHI stakeholder members currently include Jotun, iKnowHow, Armach Robotics, Notilo Plus, Hapag-Lloyd, Wallenius Wilhelmsen, DNV, the Mærsk Mc-Kinney Møller Centre for Zero Carbon Shipping, Litehauz, Port of Antwerp Bruges, ShipShave, VesselCheck, LimnoMar, Endures, CleanSubSea, the University of Maryland Center for Environmental Science (Alliance for Coastal Technologies and Maritime Environmental Resource Centre, ACT/MERC) and University of Strathclyde.
The CHI alliance is open to new members. Interested parties can contact Runa A. Skarbø, CHI project manager and senior advisor in the Bellona Foundation email@example.com