FAQs

FAQs

Impact: economic and ecological potential/ benefits/ added value

What are the economic and environmental benefits by using AIRCOAT?

To make European waterborne transport more energy efficient, more sustainable and less polluting. Providing a permanent air layer under water around a ship gives an enormous economical as well as ecological benefit:

  1. The air layer acts like a lubricating agent between the water and the ship hull, reducing drag, fuel consumption and GHG emissions.
  2. At the same time, it prevents fouling, as the marine organisms cannot attach to the ship, but have contact only with the air layer.
  3. Moreover, the air layer prevents corrosion by hindering the seawater to get into direct contact with the ship surface.
  4. Furthermore, toxic substances from the ship hull are not released into the environment, if the water does not touch the ship.
  5. Finally, the air layer between ship and water reduces acoustic emissions from the ship hull to the water, resulting in environmental benefits.
What are the advantages of AIRCOAT against state of the art coatings?
  1. The coating with the air layer is non-toxic and will have no adverse impact on the environment.
  2. Presently no other coating provides the unique combination of the above five advantages and offers such a potential of improvement.
  3. As compared to the air microbubble technology (active air lubrication), there is a big difference: In air microbubble technology, the ship remains wet, and the air does not touch the ship. In AIRCOAT technology (passive air lubrication), the ship remains dry and the water does not touch the ship.
  4. Finally, no continuous energy consuming compressed air supply is needed, it has no hull application limit (flat bottom) and does not need refit adaptions to the ship hull (air outlet) and machinery (air compressors) , hence not occupying valuable cargo space. AIRCOAT is a passive technology in which air layer is naturally formed because of the fine structure of the coating.
What business case is AIRCOAT addressing?

AIRCOAT enables environmentally friendly ship coating, which allows for reduction of drag, fouling, corrosion and acoustic emissions at the same time. Furthermore, operational and maintenance costs of ships can be lowered. Offering a refit technology for existing vessels enables a broad application.

Why is AIRCOAT important for the public / society?

AIRCOAT will make waterborne transport more energy efficient, more sustainable and less polluting. Seventy percent of all ship emissions are within 400 km of land and estimates predict that each year over 260 000 deaths are attributed to pollution from global fleet.

Technical questions: material, air layer, application, foil

How will AIRCOAT be technologically realised?

By means of implementing the Salvinia Effect on a self-adhesive foil which retains an air layer on its surface and is applied to the ship’s hull.

What is the expected effect of AIRCOAT to the buoyancy of the vessel?

Calculations show the expected buoyancy of the air volume would compensate the weight of one container (TEU). Considering typical container ship sizes, carrying 8000-14000 TEU, the buoyancy effect is negligible.

Can AIRCOAT also increase speed of small (sailing) ships?

The air retaining effect of AIRCOAT reduces drag and therefore increases the speed of sailing yachts.

Which structure sizes are aimed to be realised?

Hierarchical structures down to the micrometre and nanometre scale will be used.

Project results: objectives/ goals/ validation

What are the main objectives of AIRCOAT project?

AIRCOAT aims to introduce a game-changing hull coating technology and validate its potential to reduce emissions and increase energy efficiency, by reducing frictional resistance, reducing emission of pollutants, reducing biofouling, designing application and production procedures and improving public awareness of AIRCOAT technology.

What environmental risks does the development of AIRCOAT include?

There are no environmental risks expected. Nevertheless, physical endurance of the coating will be tested during the project to learn any disadvantages, like contribution to the micro plastic pollution of the coating.

How scalable is AIRCOAT’s business model?

Due to the application of a foil, the product is scalable to any hull geometry and any ship size. Every ship, regardless of its size, is encountering friction drag while sailing, hence AIRCOAT is scalable to all ship sizes.

Next steps: readiness level, application, strategic plan

Will AIRCOAT be available for the professional and/or consumer market?

It is the explicit aim of AIRCOAT to provide the basis for availability of this breakthrough technology in the professional as well as the consumer market. In this context, AIRCOAT will develop a feasibility study to assess the market readiness of the product/technology.

General

Where is Salvinia molesta naturally located?

Salvinia molesta is found in fresh water areas with water temperatures between 20 and 30°C. It prefers slow moving waters such as lakes and ponds. High light intensity can increase grow dramatically.

What is biomimetics?

Biomimetics (or bionics or bio-inspiration) is the transfer of biological models to innovative technical applications. This is done by mimicking working principles of nature and transferring the mechanisms into technical applications without necessarily copying them.

How can an air layer reduce the drag of a ship moving through water?

The movement of water over the ship hull causes skin friction drag, which the ship has to overcome. If a layer of air covers the ship, the water is moving along an air surface. This air-water interface and the resulting low shear flow of the water reduces the friction dramatically.

For what reason does Salvinia produce an air layer?

The plant needs the air layer for a different purpose than AIRCOAT: It needs the air layer to be able to breathe air even if drowned under water.

What have plants to do with ship hull drag?

In both cases, the air layer is used to benefit from it. Only that the benefit in plants is breathing under water while for ships it is reducing the friction, fouling and corrosion thus leading to lower fuel consumption. This transfer of a principle into a different scenario is a prime example for a biomimetic application where technology learns from nature.

What is the biomimetic Salvinia principle and how will it be used in AIRCOAT?

A surface covered with water-repellent hairs or pillars with hydrophilic (i.e. water-attracting pins) at their ends is able to keep a permanent layer of air under water. This principle will be mimicked by AIRCOAT and transferred to the surface of a foil that can be attached to ship hulls.

Does the air layer deplete over time in Salvinia and/or in AIRCOAT?

Current state of the art samples shows no depletion of air over several years under lab conditions.

PROJECT COORDINATOR

Johannes Oeffner
Fraunhofer CML
Johannes.Oeffner@cml.fraunhofer.de

COMMUNICATION CONTACT

Hadil J.S. Ayoub
REVOLVE
hadil@revolve.media

The AIRCOAT project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement N°764553.

PROJECT COORDINATOR

Johannes Oeffner
Fraunhofer CML
Johannes.Oeffner@cml.fraunhofer.de

COMMUNICATION CONTACT

Hadil J.S. Ayoub
REVOLVE
hadil@revolve.media

The AIRCOAT project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement N°764553.