Can a world-class blue water navy be ‘Green’?

Upon considering the question of having an environmentally friendly navy, the answer should not lead to an argument over what is more important, a powerful navy or a thriving environment. Instead it should consider how to integrate greener technologies, to optimise and enhance the capabilities of the fleet in its entirety.

This article was submitted to the UK Defence Journal by Ryan Miller, a 5th year student at the University of Strathclyde studying a masters degree in Naval Architecture and High Performance Marine Vehicles. This article was originally written for the UKNEST 2019 scholarship, of which the posed question was ‘Can a blue water navy be green?’. Ryan, as a successful applicant to the scholarship & recipient of the award, offers his take.

Taking inspiration from commercial shipping, naval powers must consider their impact on the environment throughout all aspects of their infrastructure. Not only considering the damaging effects during the vessel’s lifetime, but the prevention of unnecessary pollutants from design through to decommissioning. As clearly shown in the MoD Sustainability Development Strategy, the introduction of green technology is not an inconvenience to the military, but rather teeming with potential. [1]

Consider the buildings in which naval vessels are designed. As a by-product of the need for energy efficient office spaces these buildings utilise heat recovery systems on ventilation to ground source heat pumps, which is vital in reducing any harmful impact upon the environment. This ethos should not stop at architecture but rather be thrust upon the shipyards and the fleet itself. Shipyards employ powerful generators that run continuously to heat large open areas which in turn leads to surge of wasted energy. By considering modern architecture in the practice of shipbuilding, progress must be made to not only move designs forward with time but to haul construction spaces into in an energy efficient 21st-century. Upon a vessel’s launch and lifetime, its design should be sympathetic to change. The world is not yet ready for a fully renewable naval ship.

Current procedures have been developed to integrate certain systems, such as US Aircraft-carrier biofuel but we are far from eliminating the reliance on diesel [2]. For this reason, as well as the extensive lifetime of a vessel (Type 26 with a planned lifetime of 25 years minimum), combined with the accelerated rate of developments in to renewable propulsion, platforms must be able to embrace continual upgrades. An insurance that the vessel can always be its best design and that continuous development is considered and utilised. Towards the end of a ship’s lifecycle, the design becomes as important as ever, with the focus on reusable sections, recyclable materials, and possibly a re-purposed platform.

With possibilities of recycling, a thought must be given to the materials chosen from the outset of the build. Carbon-Steel and aluminium have a recyclability of 95%, compared to that of a carbon fibre composite showing only 10% recyclability, and 90% destined for landfill [3]. Yet, the added weight of the steel would lead to an increase in fuel consumption, but what about integrating the two materials? The underwater body of steel would require harsher anti-fouling, but there is the possibility of introducing a silicon or ‘fluororesin’ based foul-release product [4]?

The topside and exposed steel vessel would require to be repainted, reducing rusting, which could be addressed by utilising galvanised steel [5]? A constant push and pull of design choices. Can a world-class blue-water navy be green? It can’t afford not to be.

References

1. Military of Defence , “Sustainable Development Strategy,” Military of Defence , 2019.
2. The Guardian, “US Navy Launches First Biofuel-Powered Aircraft Carriers,” The Guiardian, 2016.
3. C. Favi, “Life Cycle Model and Metrics in Shipbuilding: How to Use them in the Preliminary Design Phases,” Procedia CIRP, vol. 69, no. 1, pp. 523-528, 2018.
4. Coatings World, “Advances in Antifouling Coatings Technology,” Coatings World, 2019. [Online]. Available: https://www.coatingsworld.com/issues/2016-10-01/view_features/advances-inantifouling-coatings-technology. [Accessed 22 8 2019].
5. Metal Supermarkets, “Marine Grade Metal,” Metal Supermarkets, 10 April 2017. [Online]. Available: https://www.metalsupermarkets.co.uk/marine-grade-metals/. [Accessed 22 8 2019].