Greening Defence: Transforming the Royal Navy for a Climate-Affected World

To world's end: HMS Protector in the Ross Sea off Antarctica. Image: L(Phot) Nicky Wilson / Wikimedia Commons / OGL v1.0

The latest Greening Defence commentary examines how the Royal Navy is quietly but ambitiously setting the conditions for a greener fleet and support infrastructure, both now and in the future. Longer-term, a sustainable source of fuel must be prioritised.

Like the British Army, the Royal Navy is preparing to operate in a climate change affected world, with rising sea levels from melting icecaps and new transit routes creating new security risks. With a current reliance on fossil fuels to power its fleet and energy-thirsty naval bases, the Chief of the Defence Staff, Admiral Sir Tony Radakin, has identified climate change as ‘a challenge that we need to play our part to address: greener ships, more energy-efficient buildings and also better utilising the infrastructure we already have’. Reassuringly, the service has adopted a pragmatic approach, establishing a number of climate-facing forums and departments to reduce their environmental impact and begin the drive towards decarbonisation. While climate change is all encompassing, the main issues the Navy face can be collated into three areas: powering the fleet; greening the fleet; and naval basing.

The motives behind tackling climate change are well known. However, with a tradition as a ‘reference Navy’, perhaps the Royal Navy faces a greater reputational risk when compared to the Army and Royal Air Force, if it does not adopt a leadership role in the push for Net Zero. Director Naval Staff, Admiral Paul Beattie, speaking at the United Kingdom Naval Engineering, Science and Technology (UKNEST) Warship Net Zero Conference 2022, itself a significant event for the Navy, claimed sustainability and Net Zero is ‘a space where we have to be more ambitious, and our ambition has to show no bounds’. Fortunately, the Navy appears to be in good stead internationally, with plans which may present an opportunity to influence global allies as they move to greener fleets.

A Coherent Strategy Aligned to Defence

The Navy has announced a three-phase approach to climate change and sustainability: Build (to 2025); Initiate (to 2035) and Accelerate (to 2050). The Phase 1 Plan will be released in Summer 2022. Initial drafts communicate a coherent and clear approach aligned to the epochs of Defence’s Climate Change and Sustainability Strategic Approach (CCSSA). Promisingly, the Royal Navy appears to have prioritised climate change at the highest level via the Navy Command Climate Change and Sustainability Group (NC3SG), chaired by Director Naval Staff. The phase 1 announcement is timely. The arrival of the National Shipbuilding Strategy will inject a £4 billion investment to build 150 vessels across the next 30 years, accompanied by a new Shipping Office for Reducing Emissions (SHORE) to drive the development of ‘green ship’ technology as well as establishing shipbuilding skills task force. Importantly, this strategy establishes a long-term framework for success and moves beyond short-term, high-cost, high-risk fixes experienced elsewhere in Defence which have resulted in a lack of investment and loss of technical expertise. This is a clear signpost to industry as to the Navy’s prioritisation of climate change.

Sustainable Fuel

Arguably the greatest challenge to the Navy is resourcing a sustainable source of propulsion. The HMS Queen Elizabeth was heavily criticised for ‘gunboat diplomacy’ and an environmentally damaging deployment to the Pacific in October 2021 (ironically just prior to COP26). While the decision for not powering the Navy’s aircraft carriers with a nuclear option appeared largely financial at the time of design, longer-term this may prove more expensive given the introduction of carbon taxes. Fortunately, and more through necessity than by choice, in 2020, the Navy has already had to change fuel types to adhere to International Maritime Organization legislation, transitioning to very low sulphur fuel oil. Globally this has resulted in a 77% drop in sulphur oxide emissions, approximately 8.5 million metric tonnes every year. This good work has continued. In November 2021, the Ministry of Defence launched a Market Exploration scheme to fund research for hybrid power solutions to retrofit to existing ships and reduce emissions by up to 40%. Autonomous electric vehicles offer a radical alternative to fossil fuels, particularly in the subsurface domain; these were being researched in the US as early as 2012 but have had mixed progress to date. However, while initiatives in both the US and UK are promising, the Royal Navy should be under no illusion that a sustainable fuel source remains key to unlocking a greener future.

Future-Proofing the Fleet: Modular Ship Building

While a sustainable source of propulsion is currently elusive, the Navy has implemented a range of existing technologies to both monitor climate change and reduce its impact on the environment. HMS Tamar and HMS Spey have installed selective catalytic reduction systems to reduce nitrous oxide emissions by up to 97%, as well as water treatment technology to sanitise waste. HMS Glasgow is the first of eight Type 26 Frigates to be painted with environmentally friendly, anti-fouling paint to limit marine growth, and has undergone hydrodynamic redesign to add additional speed without the need for extra power. These initiatives provide quick wins to ignite the Navy’s climate change programme and may placate civilian environmentalists in a way which other sections of Defence have yet to achieve.

The Navy has recognised the need for cultural change to combat climate change, attempting to embed sustainability across the service in its entirety

Longer-term, the Royal Navy is futureproofing the current fleet through modular ship building and the ability to incorporate as yet undiscovered technologies. Speaking at DSEI in 2021, Matt Darkin, Director of Ships Acquisition, Defence Equipment and Support, claimed, ‘we’re starting today, with the baseline of today, to make sure that the vessels we are building are as environmentally compliant as they can be moving forward’. As with the other services, the Royal Navy will exploit technologies and advancements made within the commercial sector as a fast follower of industry. This gives the Navy the flexibility to refit vessels within their life cycle, ensuring that the service can maintain and improve capabilities despite changes to the maritime environment. This approach is also politically appealing, saving time and taxpayer money, which is particularly significant given the exorbitant financial and environmental costs associated with building new ships from scratch.

Naval Basing

Defence infrastructure has already been discussed in previous Greening Defence articles; naval bases merit particular mention as one of the largest consumers of energy in Defence. To its credit, the Navy has centralised discussion, convening the Net Zero Carbon Naval Base conference in 2020 and following it up with a Tri-Base Net Zero Carbon Approach discussion in 2021, contracting Innovate UK KTN to ensure breadth of innovation. HMNB Portsmouth is the flagship for eco-development, constructing the first carbon neutral buildings and earning three environmental awards. Of note, the Queen Elizabeth-class Forward Logistics Centre has over 750 solar panels with the potential to produce 256 MWh and saving 72 tonnes of carbon emissions in year one, while the introduction of electric vehicles, wind turbines and energy efficiency building upgrades all appear promising. Focusing on a singular site as a case study is prudent, but particularly so given the shrewd use of project funds from the aircraft carrier programme to integrate greener facilities – the Army, with its substantial estate, should take note. However, the Navy must not rest on its laurels. The lessons and success at Portsmouth must be transferred into other naval bases such as HMNB Devonport (Plymouth) and HMNB Clyde (Faslane). This needs to be implemented now rather than waiting for phase 2.

Factors for Success

At the start of the Greening Defence series, we identified the need for cultural change to combat climate change. To its credit, the Navy has recognised this requirement, attempting to embed sustainability across the service in its entirety. The formation of the Naval Green Network and the potential integration with existing organisations such as the Carbon Literacy Project offer good methods for making sustainability business-as-usual. Wider Defence must understand that the environment is an increasing priority for its younger generation of recruits. HMS Tamar’s 50-strong crew, with an average age of 27, proudly class themselves as a ‘millennial ship’ and place ocean conservation as a priority on board. This is a lesson that the higher echelons of Defence must both recognise and exploit as an opportunity; here is a workforce that is willing to act to save the planet.

By using existing experience and tools, the Navy will make climate change mitigation second nature rather than an inconvenience

Perhaps the Navy’s success in embracing environmental concerns should come as no surprise given operational experience monitoring climate change in the polar regions. HMS Protector is currently on a five-year mission to support international research into wildlife and climate change in the Antarctic; this is not a new concept to the Navy. Additionally, there are several existing tools that safeguard the environment while facilitating the freedom to operate. Although recently superseded, the Marine Environmental and Sustainability Assessment Tool (MESAT) explored, justified and recorded whether negative impacts to the marine environment existed while Environmental Protection Guidelines (Maritime) is a simple system which identifies where UK Marine Protected Areas are located and provides mitigation measures. By using existing experience and tools, the Navy will make climate change mitigation second nature rather than an inconvenience; this can only be a good thing for the future.

To conclude, the Royal Navy has a bold vision to create one of the greenest fleets in the world; it has already used existing technological innovations to become more eco-friendly. This is underpinned by a modular approach to shipbuilding, futureproofing the Navy for both the short and long-term. Their Climate Change and Sustainability Phase 1 Plan outlines a series of 31 foundational tasks which covers every aspect of the service including sustainable culture and behaviour, governance and HQ, procurement and industry, and commercial and finance. The proposals have the potential to deliver environmental benefits while concurrently improving capability, achieving financial savings, adhering to political legislation, maintaining reputational status, and improving the lived experience of its millennial generation; the plan feels holistic in concept. However, while some may downplay the significance of the Royal Navy’s work to date, the senior service should have confidence in their robust and proactive strategy, supported at the highest level. That said, the long-term issue of resourcing a sustainable and eco-friendly method of propulsion remains key; while work has already begun, carbon emissions from existing fuel consumption have the potential to overshadow and negate any good work in other areas without resolution.

The views expressed in this Commentary are the authors', and do not represent those of RUSI or any other institution.

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Dr Sarah Ashbridge

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Lieutenant Colonel Alistair Beard

Former Army Visiting Fellow

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