The defence sector is intensifying its efforts to reduce carbon emissions and become more sustainable. A study estimates the defence sector emits 500 megatons to 1 gigaton of CO2 annually (1–2% of global emissions), mostly from military platforms (65–70%), stationary assets (~30%), and the supply chain. Some emissions are offset by military-owned land 1. Between April 2022 and 2023, defence emissions totalled 3.1 million tonnes of CO2 equivalent, representing 50% of UK central government CO2 emissions and 1% of the UK’s total emissions 2. These figures highlight the urgent need for change.
The UK Ministry of Defence (MoD) has set ambitious goals as part of its defence sustainability strategy to reach net-zero emissions across all its operations and infrastructure by 2040. By 2050, the MoD aims to offset the carbon footprint of its equipment by creating a carbon-negative estate. A key part of this plan is the Defence Supply Chain Strategy (DSCS), which focuses on improving the resilience of supply chains by prioritising reliability, service quality, and environmental sustainability. This strategy will involve redesigning supply chains to better handle external challenges and climate-related risks.
The MoD is prioritising sustainability in its procurement processes, encouraging suppliers to adopt greener practices and provide sustainable products and services. In response, Unipart has compiled an overview of key trends and legislative changes shaping sustainability within the defence sector. Alongside this, Paul Lyall, Associate Director of Defence at Unipart, offers practical recommendations to help defence companies proactively address these challenges and adapt to evolving regulations.
Moving towards a circular economy
The UK government is dedicated to advancing a circular economy—an approach centred on reusing resources to reduce waste and minimise environmental impact. This transition is vital for achieving net-zero emissions and has become a key priority across various sectors, including defence. To drive this effort, the government is establishing a Circular Economy Taskforce, structured in phases with clearly defined goals and recommendations for each stage.
Phase One (October 2024 – January 2025)
The initial phase focuses on defining key elements, establishing metrics and targets, and formulating early recommendations. The outputs from this phase will primarily draw on existing practices, analysis, and evidence provided by the UK government and Taskforce members.
Phase Two (January – October 2025)
The second phase will deliver a comprehensive Circular Economy Strategy for England. This strategy will outline interventions, priorities, and roadmaps designed to drive the circular economy transition over the next decade and beyond. Key deliverables include finalised metrics, sector prioritisation, costed policy roadmaps, behaviour change strategies, and a robust monitoring and evaluation plan, all underpinned by evidence and analysis.
Paul, emphasises the importance of this transition: “A circular economy isn’t just about recycling; it’s about designing systems where materials and resources are continuously reused. For the defence sector, this could mean everything from the way it manufactures and manages equipment to how it sources materials and manages waste.”
Reducing emissions and strengthening accountability
The UK government plans to reduce emissions from public sector buildings by 75% by 2037 3. To support this, new monitoring guidance will be released in 2025, covering public sector organisations in England and central government sites across the UK, including Ministry of Defence locations. This guidance will align with existing policies and funding schemes such as the £2.5 billion Public Sector Decarbonisation Scheme.
The UK government has also announced draft legislation to regulate ESG rating providers, with plans to introduce a final law in early 2025 4. This move aims to improve transparency, align with EU standards, and support sustainable investments. The regulation will help boost economic growth and ensure industries like defence aren’t unfairly impacted by inconsistent ratings. Industry groups back the change, highlighting the need for clearer and more consistent standards.
In line with these government initiatives, the defence sector is increasingly adopting green technologies and practices, including energy-efficient solutions, eco-friendly materials, and autonomous systems that reduce resource consumption. The sector is also exploring alternative energy sources and more sustainable supply chain practices as part of the broader defence sustainability strategy:
Geothermal energy
The UK defence sector is exploring geothermal energy as a cleaner, more reliable alternative to solar and natural gas. Geothermal power could reduce emissions while enhancing energy security, supporting operations in conflict zones, and providing backup power for national grids. Paul points out that “the defence sector has a unique opportunity to leverage geothermal energy as a strategic asset. The power generated could be shared with national grids, enhancing energy security and supporting operations in conflict zones. Additionally, it could help strengthen relationships with partner nations by offering energy technologies that enhance their defence capabilities.”
Hybrid and electric technologies
The British Army is increasingly trialling hybrid and electric technologies to improve vehicle performance, reduce emissions, and enhance operational efficiency 5. Technology Demonstrator #6 (TD6) is testing Hybrid Electric Drive (HED) on a range of vehicles, including the SV truck, FOXHOUND, and JACKAL. Early results show that HED technology could improve vehicle performance, reduce logistics costs, and lower emissions, marking a significant step toward greener, more efficient military operations as part of the defence sustainability strategy.
Project LURCHER is another key initiative exploring the potential of electric power in military vehicles 6. By testing electric Land Rovers, the project has shown promising results, such as increased speed, improved safety, and reduced visibility, although challenges related to maintenance and training remain. Paul explains: “The potential of new electric technologies across the defence sector needs to be investigated, especially if they lead to greater operational effectiveness. These technologies promise to reduce emissions, lower operational costs, and make our armed forces more capable and resilient.”
Electric autonomous systems are being explored as a way to replace traditional vehicles used for tasks like transporting medical staff. This innovation would not only reduce emissions but also lower security risks for personnel in dangerous environments.
Drones, both military and civilian, have played an increasingly vital role in modern warfare 7. Electric UAVs, in particular, can offer improved safety and reduced emissions by reducing the need for personnel to be on the ground for reconnaissance. This innovation could also support humanitarian aid and disaster relief efforts, offering both safety and environmental benefits.
AI and technology for a greener future
Artificial Intelligence (AI) is helping make defence operations more sustainable. With increased funding from the UK government for green AI projects 8, this aligns with the country’s 2050 Net Zero target. The Ministry of Defence’s Defence Artificial Intelligence Strategy focuses on using AI to improve efficiency and reduce environmental impact, which is a crucial part of the overall defence sustainability strategy.
AI can support sustainability in defence by:
- Extending equipment life through predictive maintenance, better stock management, and less waste.
- Improving energy use in military facilities to reduce CO2 emissions.
Paul sees AI as a key enabler, saying, “AI will help the defence sector achieve its sustainability goals by improving efficiency, predicting equipment failures, and reducing the need for physical resources and the flow of materiel between the UK strategic base and future theatres of operations . It’s not just about cutting emissions—it’s about enhancing operational effectiveness and lowering costs.”
The defence sector is exploring AI’s potential, with the Defence Science and Technology Laboratory (Dstl) leading the way. Dstl applies AI, data science, and machine learning to tackle defence and security challenges, such as intelligence analysis. The ongoing exploration of AI will play an important role in future defence sustainability and operational efficiency.
Preparing for changing sustainability challenges in defence
With evolving trends and legislation shaping the landscape, Paul highlights steps defence companies can take to address emerging sustainability challenges. To stay competitive and align with government and industry expectations, they should:
- Invest in sustainable technologies: Adopt energy-efficient systems, hybrid and electric technologies, and renewable energy sources to reduce the need to transport and protect large quantities of fossil fuels. Adopt predictive maintenance systems to forecast and pre-empt component failure, thereby decreasing downtime.
- Prioritise the circular economy: Transition to a circular economy by embracing practices such as equipment recycling, repair, and resource reuse. Increase the activities that can be performed forward in a theatre of operations to improve availability and streamline the international supply chain.
- Stay ahead of regulations: Monitor legislative changes related to carbon emissions, ESG ratings, and procurement standards. Ensure compliance and consider the long-term business benefits of sustainable practices at all stages of operations.
- Build sustainable supply chains: Work with industry partners to improve sustainability, cost, and resilience. Reduce waste, minimise packaging, and promote eco-friendly logistics solutions. Embrace AI and automation for better resource management.
- Develop green procurement strategies: Enhance supply chain resilience by selecting environmentally conscious suppliers. Integrate sustainability criteria into procurement processes, encouraging suppliers to deliver environmentally friendly products and services, and ensuring the materials used meet both quality and sustainability standards.
- Prepare for circular economy taskforce initiatives: As industry-backed initiatives evolve, defence companies should be ready to engage with the Circular Economy Taskforce and adopt the recommended strategies to build more sustainable practices.
“Sustainability is no longer a distant objective but a fundamental requirement. Defence companies that embrace these changes will not only align with government expectations but also position themselves as leaders in an increasingly sustainability-driven industry.” – Paul Lyall
Unipart’s commitment to defence sustainability
With decades of experience in integrating sustainability across various sectors, Unipart is committed to supporting the defence industry in its sustainability journey. Our focus on environmental stewardship has led to global recognition through several awards, reflecting the positive impact of our efforts to reduce environmental harm.
Jen Hunt, Unipart’s Sustainability Director, shares, “Since 2021, we have reduced all three scopes of carbon emissions by 9%, including a 13% reduction in Scope 1 and 2 operational emissions, while also growing the Unipart business significantly over that time. These results reflect a collective business wide effort, in discrete projects leading to carbon reduction but also our dedication to continuous improvement and carbon consciousness.”
Sustainability is a core part of our corporate responsibility and culture, with every team member contributing to ongoing efforts. We are focused on supporting a lower-carbon future and improving the efficiency of our operations.
We can partner with you to:
- Deliver innovative engineering and manufacturing solutions.
- Optimise stock flow to improve efficiency.
- Reduce energy consumption across operations.
- Maintain equipment based on condition to maximise lifespan.
- Work to reduce waste and minimise the use of single-use plastics.
- Offer repair, recycling, and disposal services that make best use of resources.
- Provide management decision tools to track carbon usage, enabling data-driven decisions for optimising operations and improving outputs.
As the defence sector works towards its sustainability targets, Unipart is here to help tackle challenges and seize opportunities.
Contact us today for customised solutions to optimise your defence supply chain.
References
- Roland Berger – Defence Zero. 2023
- Gov.UK – Reduce impact of defence on climate change. 2024
- Gov.UK – Public sector emissions monitoring and reporting guidance: timeline. 2024
- Reuters – Britain to propose law next year to regulate ESG raters. 2024
- Gov.UK – Defence: sustainability as a competitive advantage. 2024
- Babcock International – Project Lurcher. 2025
- Gov.UK – Defence: sustainability as a competitive advantage. 2024
- Gov.UK – AI to help UK industries cut carbon emissions on path to net zero. 2023