Kristian Lewis Simpson-Davies

Overcoming barriers to decarbonising the defence estate: An enalysis of GHG abatement on an RAF estate

Global warming is expected to surpass 1.5°C by 2035, potentially reaching 2.2-3.5°C by 2050, intensifying climate impacts (IPCC, 2023). The UK aims for net zero emissions by 2050, with the Ministry of Defence (MOD) aiming to contribute to this goal while simultaneously maintaining military capabilities (Preston, 2020) (House of Commons Defence Committee, 2023). Given that the MOD's is responsible for ~1% of the UK’s greenhouse gas (GHG) emissions, their decarbonisation journey will need to be achieved through its estate.

This research develops a decision-making hierarchy that extends beyond the conventional triple bottom line by incorporating military-specific considerations. Using the Royal Air Force (RAF) Station Headquarters (SHQ) as a case study, it explores GHG abatement measures within the MOD estate. Through interviews, criteria weighting and rank-based prioritisation was established to analyse how proactive and reactive retrofit scenarios, along with service personnel perspectives, influence GHG abatement suitability. The Analytical Hierarchy Process (AHP) Multi-Criteria Decision Making (MCDA) was then employed to demonstrate this impact and guide recommendations.

Results revealed clear prioritisation trends: Proactive decision-making prioritise social elements, while reactive scenarios shifted focus toward military and economic considerations. This shift directly influenced GHG abatement measure preferences. Measures like Loft Insulation performed well across both settings due to strong quantitative performance across multiple criteria. Whereas, measures like Internal Wall Insulation consistently ranked poorly, especially in reactive situations, due to limited financial and technical viability. The study highlights challenges in achieving a net zero estate due to: shifts in priorities between ranks; limited focus on investment efficiency; and a military focus considered exclusive of sustainability. The findings emphasize the need for a common unit-level framework, reduced reliance on reactive measures, and improved financial practices to support long-term sustainability decisions.