Spectral Imaging Powered Ship Hull Biofouling Detection and Cleaning

The build-up of microorganisms, plants, algae and animals on submerged marine structures can alter the hydrodynamics of the ship, increasing drag, fuel consumption and emissions. There is currently no efficient way to evaluate the hull when the ship is in the water, and taking it out results in down-time that is costly for ship operators. Furthermore, if a ship is not taken out regularly for inspection, the likelihood of biofouling having progressed increases, resulting in the need for harsher cleaning methods that can damage the hull painting or coating. The EU-funded SleekShip project is developing a semi-autonomous underwater vehicle that will both detect slime at early stages using a multispectral camera and clean it softly with cavitation jetting. The operation can be done while the ship is docked at port for other operations or moored at sea. Commercialisation will enhance the competitiveness of ship owners while reducing fuel consumption and emissions.

Marine biofouling has a tremendous economic and environmental impact; it can lead to >€1m in lost revenue per ship per year in fuel overconsumption alone. The International Maritime Organization estimates that gas emissions may increase between 38% and 72% by 2020, unless corrective measures are taken.

The only way to mitigate biofouling is to detect it at an early stage (Level of Fouling – LoF 1), while it can still be cleaned with soft methods that do not damage hull paint or coating. With current approaches this is impossible, particularly within port waters as they are heavily turbid and inhibit visibility. Inspections outside port waters induce charter-off time that costs >€20k per day and are thus avoided by ship operators.

SleekShip comprises a Semi-Autonomous Underwater Vehicle (SAUV) carrying a hyperspectral camera that captures light wavelength bands where light backscattering is less and the slime is easier to distinguish despite contamination. The inspection can take place in port waters while the ship is docked for other operations thus no additional charter-off time is incurred. An integrated cavitation-based cleaning tool allows for 100% paint-safe cleaning.

By detecting biofouling early, ship owners will be able to achieve >€1.3m savings per vessel annually by reducing fuel overconsumption and paint/coating damage caused by hard-brush cleaning.

Our consortium comprises SubseaTech, a dynamic manufacturer of underwater robots, QCELL, a high-tech SME specialising in hyperspectral imaging, M.Danchor a leading cleaning and inspection services company, TWI, the global leader in image-based underwater inspection technologies and Danaos, a NYSE-listed containership owner.

Through SleekShip we aim to achieve sales of €41m, generating €17.9m profits and >110 jobs while helping the shipping industry save €3.4bn per year and reduce CO2 emissions by 115m tonnes over the 5 years after market launch. The Net Present Value ROI is 4:1 on EC funds with a grant.

More information about the project can be found at the project website.