HullWiper | Shipping’s greener future

Shipping’s greener future

15 Nov 2022

Screenshot 2022 11 15 080331

Authored by HullWiper.

For years, maritime news headlines have been dominated by shipping's role in the current climate crisis and its efforts to limit the damage caused. It's not surprising, if shipping were a country, it would be ranked around sixth in the world for its contribution to climate change.

With more than 80% of global trade volume and about 70% of trade value transported by ships, shipping is essential to the growth of international trade and economic development. The number of vessels navigating our oceans is growing along with global trade, which adds to the industry's 3% annual global emissions of greenhouse gases (GHG).

The international shipping community is making green strides in its commitment to reduce its CO2 emissions by at least 50% by 2050 from 2008 levels of approximately 4.5%. Let’s look at some examples:

Regulatory bodies, such as the International Maritime Organization (IMO), have put in place a number of policies and regulations, including the mandatory Energy Efficiency Design Index (EEDI) for new ships aimed at promoting the use of more energy efficient equipment and engines and the Ship Energy Efficiency Management Plan (SEEMP), an operational measure that establishes a mechanism to improve the energy efficiency of a ship in a cost-effective manner.

The Global Industry Alliance (GIA) developed the Just-In-Time (JIT) Arrival Guide to reduce the time vessels spend at anchor, ease port congestion, and provide a practical means of lowering greenhouse gas (GHG) emissions.

Under the "Fit for 55" set of proposals, the European Union (EU) is revising its climate, energy and transport laws to reduce emissions by at least 55% by 2030. The reforms include a sustainable fuel mandate. From 2023, EU Emissions Trading Scheme (ETS) will include shipping emissions - shipowners, regardless of flag, will have to buy carbon allowances to cover all emissions during EU voyages and half of international voyages that start or finish at an EU port.

But if we delve deeper, more need to be done. A proactive biofouling management plan for vessels is necessary to reduce CO2 output and improve energy efficiency.

Beneath the surface

One of the major contributors to the carbon dioxide emissions from ships is biofouling, which is the buildup of aquatic microorganisms, plants, algae, or small animals on ship hulls. A vessel's submerged area begins to accumulate marine biofouling minutes after contacting the water and, if left unattended, reduces operational efficiency and increases drag and fuel consumption.

The GloFouling Partnerships and Global Industry Alliance (GIA) for Marine Biosafety released an in-depth analysis (see below link for the full report) about the importance of maintaining a hull free from biofouling with data covering vessels operating in the Equatorial and Mediterranean regions. It examines the impact of biofouling and how current industry biofouling management practices affect ship efficiency. I'll briefly unpack some of the findings, with a focus on the relationship between biofouling and GHG output as well as different types of anti-fouling scenarios and their impact on fuel savings.

NOTE: The report's findings are based on an updated knowledge assessment and new research.

A 0.5mm layer of slime covering up to 50% of a hull surface could result in a 25% increase in GHG emissions. GHG emissions could increase by up to 90% for medium calcareous fouling surfaces and severe biofouling conditions, such as a light layer of small calcareous growth (barnacles or tubeworms), could result in a 60% increase in GHG emissions. The report cites a study that estimated that if all international ships were biofouling-free, global GHG emissions from ships could be reduced by 19% per year (or 198 million tons of CO2e).

Using a cost estimate of US$572.50 per metric ton of fuel oil (FO), the report looks at the difference a (hull) clean would make to a ship owner/operators bottom line.

Vessel hull anti-fouling coatings is your first line of protection against marine fouling. Further, as seen from this study, regular and proactive hull cleaning is key to managing carbon emissions and operating expenses (OPEX).

Doing our part

Increasing number of ports around the world require vessels to report how biofouling was managed before entering their waters. Although not mandatory, the IMO Resolution MEPC.207(62) recommends every ship have a Biofouling Management Plan and Record Book.

HullWiper’s eco-friendly hull cleaning system provides ship owners and operators with the proactive solution needed to meet the shipping industry’s move toward clean and green operations. Our innovative, eco-friendly brush- and-diver-free underwater hull cleaning system uses adjustable high-pressure seawater to dislodge waste materials and remove fouling and invasive aquatic species (IAS) without the scrubbing, harsh chemicals or abrasives employed for traditional methods. Unlike traditional brush cleaning, HullWiper leaves expensive antifouling surfaces intact and does not harm the delicate marine environment. It is the only operational Remotely Operated Vehicle (ROV) that offers a unique onboard filtration system to safely capture all removed biofouling from vessel hulls for safe disposal onshore by a locally approved environmental waste company. Ship owners and operators can compare the financial benefits of hull cleaning with the HullWiper compared to traditional methods of divers with brushes with our online fuel savings calculator.

All our global operations are in line with International Marine Contractors Association (IMCA) and IMO guidelines and carried out in accordance with local legislation. HullWiper is an active member and participant in regulatory bodies such as BIMCO and NACE and we are one of four founding members of the IMO’s Global Industry Alliance for Marine Biosafety.

We can also offer an onboard solution enabling any type of vessel to remove fouling on demand. The ROV can be included in the design phase for newbuilds and launched by way of either an on-deck solution, door, or hatch in the side of the hull through a moon pool. Ships that operate as standard (think cruise) on a tight schedule can perform a partial or full hull clean on planned rotations


Thus – or so or consequently - the hope is that the future of shipping is looking greener than ever before. And there are positive indications that they are with the IMO Secretary-General Kitack Lim opening COP27 on Producing Future Marine Fuels and Hapag Lloyd building 12 new ultra large container vessels that are going to be powered by gas, with the target to operate them carbon neutral in the future. There are a number of incentives taking place within the industry, let’s all hope that people walk the talk.


GEF-UNDP-IMO GloFouling Partnerships Project and GIA for Marine Biosafety, 2022. Analysing the Impact of Marine Biofouling on the Energy Efficiency of Ships and the GHG Abatement Potential of Biofouling Management Measures.

Page references:

· Executive Summary, Ships Biofouling: Quantifying the Potential Impact if Unmanaged, Page 11, Paragraphs 3 and 4 (Biofouling and GHG % Emissions).

· Chapter 2, Biofouling Prevention and Management Measures, 2.2.2 Additional Research, Page 38, Paragraph 3 (Fuel Price and Savings Estimates).

· Chapter 2, Biofouling Prevention and Management Measures, 2.2.3 Result: Equatorial Region, Table 14: Difference in the total fuel cost with different anti-fouling scenarios (Equatorial region), Page 40.

· Chapter 2, Biofouling Prevention and Management Measures, 2.2.4 Result: Mediterranean Region, Table 16: Difference in the total fuel cost with different anti-fouling scenarios (Mediterranean region), Page 45.