Ship eco-design


The navies of the 21st century are demanding an ever-higher level of technicality and performance. How can the environmental criterion be integrated into the overall performance criteria of a ship? Gaëlle Rousseau and Léonie Rolland* explain this naval eco-revolution that is taking seed in the minds of industrial companies and navies.

vignette-rolland-rousseau parole d'expert n°1

Is awareness of the need to reduce the environmental impact of ships simply due to changes in the regulations?

G.R.: As a result of the constant increase in maritime traffic, environmental regulations have been made stricter and stricter for ships over the last forty years in order to protect our coasts and our oceans. Even if carbon dioxide emissions from ships remain lower than those of other modes of transport, maritime transport emits three times as much sulphur dioxide as road transport (90% of global transport is by sea). The military ships of the NATO member countries are exceptions to the rule, using fuel oil with low sulphur content. The main reference documents are taken from the International Maritime Organisation (IMO) and the International Convention for the Prevention of Pollution from Ships: MARPOL (MARitime POLlution), updated since 1973. It covers all the pollution in overboard discharges (hydrocarbons, garbage, waste water and gas emissions).

Parallel to this, our company has undertaken a transition to a new economic model, the circular economy, which aims to move from a process of reducing impact to a model which creates aggregate value, by getting inspiration from natural ecosystems and minimizing the depletion of natural resources.

L.R.: The strong incentive to integrate environmental stakes in naval design cannot just be explained by a change in regulations, it is also driven by a political will at the French state level and the customer’s will. Even though operational performance remains primordial, it converges more often than not, with respect for the environment.

“The convergence between operational performance and respect for the environment”

Why is the convergence between operability and eco-design of potential interest to navies?

L.R.: There are many possible actions which call on good sense such as: Energy savings which contribute of course, to improved autonomous operation at sea and savings in material, a lighter and more easily movable ship. Likewise, the repairability of a product, due to more robust solutions, which facilitates and reduces maintenance costs. And finally, controlling the composition of our products which provides us with tools and elements to plan for their end of life management.

G.R.: The absence of substances banned by the regulations means quite simply that navies can anticipate the obsolescence of their equipment. Moreover, the use of equipment designed to both reduce the environmental impact and comply with the strictest rules means that customer navies can navigate on all the world’s seas without any restriction, giving them an operational advantage. Resolving the various problems related to Eco-design in fact gives rise to a multitude of operational advantages.


How is an environmentally-friendly ship designed?

G.R.: Eco-design is an approach intended to minimize the environmental impacts generated by the project, and this, from the design phase. This process which we implement using tools such as the Life Cycle Analyses means that we avoid any transfer of pollution in the design choices and propose products and solutions which conserve the intrinsic performance levels of the ship. Indeed, a product is analyzed with respect to all of its life cycle using a multi-criteria approach: from manufacture to operation, from maintenance to deconstruction. The results are conclusive and permit, in the long run, a reduction in the life cycle cost of the ship.

L.R.: The Research and Development areas on which we are working at DCNS are the reduction in energy consumption, the performance levels of the propulsion system (notably by research into the processing of nitrogen oxides and engine micro particles), innovation with innovative materials and the reduction in waste by improving either its storage (compactness and safety) or its treatment and optimization. For example the FREMM multimission frigate fully embodies the MARPOL 2010 regulations. All of the waste water is treated by a treatment plant designed and integrated into the platform, and fuel oil consumption is 20% lower than that of the previous-generation frigates. This is a real step forward and it is not the last.


* Gaëlle Rousseau is Eco-design Manager and Léonie Rolland, Environmental Analysis Manager at DCNS, based on the Lorient site.



The Life Cycle Analysis is method which assesses the environmental impact of the ship in terms of its life cycle, from its design to its deconstruction, via the operation phase which groups both navigation and maintenance.

Water pollution covers pollution from bilge water, waste water, garbage, ballast water and anti-fouling paints.

Air pollutant emissions principally cover sulphur and nitrogen oxide emissions (SOx and NOx) and engine micro particles.

Pollutant anti-fouling paints group the ship hull treatments which are prohibited due to the transportation of aquatic organisms outside of their environment or from one ocean to another, and thus introduce pathogenic or invasive organisms.