The Sonihull system

Sonihull offers a range of systems with two, four and eight transducers. A constant 220 VAC needs to be on 24/7 and the system consumes 3.6 Watt an hour per transducer. The control box has an IP65 rating and the transducer IP68. Each transducer comes with a 7.5-metre cable which can be extended up to 80 metres. The Sonihull8 version allows you to control eight transducers from one box with an internal registration logging the hours of operation. In case of a power failure the system will automatically start up after the power has been recovered and use the default value registered. As every transducer can be individually controlled from the LCD screen you can see how long each unit has been switched off.

  • Prevents… Biofilm… Avoids… Prevents…
  • Destroys… No bio… no organic ….

Why Sonihull?

Not harmful to sea life

The emitted ultrasound does not harm the environment as it emits frequencies that only prevent biofilm and destroy unicellular organisms. Living beings such as fish, dolphins, whales or humans are not affected by these ultrasonic waves.

Easy installation

Ultrasonic anti-fouling is a preventive system so it is an essential precondition that you start with a clean surface. The installation of Sonihull is very easy and the ship doesn’t even have to go into dry dock or have its box coolers drained. The installation can be carried out at any time without drilling, welding or any penetration of the surface.

Environmentally friendly

Traditionally, poisons (biocides) have been used to kill organisms that settle on raw seawater surfaces like hulls and box cooler pipework. Environmental legislation covering the use of poisonous metallic biocides in antifouling systems is tightening and marine-based industries are looking for more effective means of preventing unwanted marine growth on their vessels and inside their equipment. Unlike conventional antifouling coating systems, Sonihull does not release poisonous biocides that kill marine organisms or use ablative coatings that leave microplastic pollution in their wake.

Cost savings

  • Sonihull is completely maintenance free
  • Sonihull is a one-time investment
  • Marine growth on a ship’s hull can increase costs by up to 60%
  • Less time needed for drydocking

Compared to impressed-current antifouling systems, Sonihull can reduce capital and MRO costs by up to 85%.

How ultrasonic antifouling
prevents growth

The Sonihull system works by emitting specific and scientifically researched, low-powered, pulsed ultrasonic frequencies from a digital control unit via transducers that are in direct contact with the inside of the protected surface. The surface acts as a sound board, carrying the sound waves and creating a microscopic environment of moving water molecules over the entire underwater profile of the surface. This prevents growth as the cell structures of the algae and microorganisms are targeted and cannot survive.

The cleaning effect of ultrasonic systems is based on the induction of cavitation. The effect is achieved through the microbubbles which are created when a sufficiently high, negative pressure is exerted on a liquid. Compression and decompression waves pass through the liquid very quickly. Once the waves are strong enough they break the forces of attraction in the existing molecules and generate gas bubbles. The collapse of the gas bubbles causes a rapid and extreme rise in temperatures of up to 4000°C  and a major rise in pressure, both of which lead to the generation of free radicals with strong oxidative properties.


What is biofouling?

The formation of fouling begins with the development of a macromolecular film of sugar and protein when a body is exposed to water. This is followed by a colonisation of bacteria for which the film serves as food and promotes their attachment. The next colonisers are microorganisms such as single-celled algae, animals and fungi. The substances excreted by these microfoulers in turn creates a biofilm, which can quickly grow into a thick layer and attract pelagic larvae and the spores of microorganisms. These larvae then develop into larger organisms that form the macrofouling.

A distinction is made between hard fouling, which includes types of crustaceans, barnacles and sea pocks, and soft fouling, which includes algae and soft corals such as sea anemones.

Problems caused by biofouling

Biofilm fouling causes many problems such as corrosion, formation of micro-organisms and deterioration of heat transfer as well as cross-section reduction and blockages. Fouling on hulls has an economic impact for owners and users of the ship. The vegetation increases the weight of the ship and at the same time the flow resistance, which can lead to slower travel and up to 30% higher fuel costs. In addition, docking is necessary at shorter intervals and the ship’s hull can be damaged. The annual costs of fouling worldwide are estimated to be at least $200 billion!

Just to reiterate

Sonihull is a preventive system so it is essential you start with a clean surface, whether that be a box cooler, sea chest, filter, thruster or hull (by divers or on the hard). Once a vessel is cleaned, the Sonihull system needs to be installed at the latest within a week of the boat coming back into contact with water. The sooner after cleaning the better in fact as any microorganisms that attach themselves in-between cleaning and the ultrasonic treatment will be not removed.