The global defense industry is booming—and with it its emissions. However, investing in technological advancements could reverse this trend.
Russia’s war of aggression against Ukraine and rising geopolitical tensions have driven governments to expand their military expenditures and increase procurement. But the growth is not limited to traditional applications. A number of new technologies are also seeing more uptake and companies’ research departments are benefiting from higher sales. Besides sought-after drone technologies and artificial intelligence applications, the electrification of military vehicles is an often-overlooked segment where growth is happening—potentially reaching market volumes of $20 billion by the end of the decade.
Whereas non-tactical vehicles operating, for example, on domestic military bases are easier to replace and can already provide significant cost-savings today, the development of electric vehicles (EVs) for combat is more challenging. The benefits of electrification could be multifold. EVs typically require less maintenance, and their adoption would lead to reducing the militaries’ dependency on fossil fuels, which are often difficult to transport to the frontline.
Looking into the future, questions of compatibility of traditional combustion engine machinery with civilian infrastructures could also arise in the medium term, as the increased use of EVs will increasingly displace traditional fueling stations. However, the advancements also come with new risks. Electrification will go hand-in-hand with increased use of digital technologies in military vehicles and machinery, which will henceforth require advanced cyber security measures.
Substantial Effects
From a climate perspective, possible emissions reductions would be substantial. For comparison, while the world’s militaries account for 1 to 5 percent of global greenhouse gas emissions, shipping and aviation make up around 2 percent. However, this does not fully reflect the effects over the whole lifecycle—from embodied emissions of energy-intensive steel to the fuel-intensive operation of machinery or transport, plus the potency of infrastructural and environmental destruction caused by warfare, requiring vast resources to rebuild and recover.
NATO had already released a “green defense” framework more than a decade ago in 2014 and allied countries such as the United States have since moved forward in setting emissions reductions targets for their military. Most recently, the German defense ministry released its “Strategy on Defense and Climate Change” (March 2024), which closely examines the changing risk landscape.
The potential spillover effects of less polluting solutions in the defense sector on civilian applications should also not be underestimated. In some contexts, such as disaster response, the challenges to substitute emissions-intensive applications in already difficult-to-manage supply chains can be technically similar to those of military operations.
Retiring Generators
One widely-used old technology is diesel or gasoline generators, which serve as an off-grid and emergency power supply solution. A study commissioned by the World Bank’s International Finance Corporation estimates 25 million generators to be in use in developing countries, two-thirds of which operate in addition to existing, but unreliable, electricity grid infrastructures. They assume that around 55 billion liters of fuel are consumed in these generators per year. In Sub-Saharan Africa, more than 20 percent of total diesel usage stems from generators. In developed nations these generators often come into use after natural disasters, such as flooding events.
Diesel combustion poses significant health risks, in particular when generators are operated near residential areas and businesses, as is often the case. In addition to their effect on the global climate through the release of CO2 into the atmosphere, there are the health risks associated with the release of particulate matter directly impacting air quality.
On construction sites in Europe, where diesel generators are regularly used when energy needs for large machines cannot be met through the local grid, battery systems have been successfully deployed by some companies as a substitute for the dinosaur technology. Moreover, research institutes, including Germany’s Fraunhofer Institute, are looking to replace diesel generators with hydrogen, which could be sourced from renewable energy. Another option could be the use of off-grid solar systems in combination with traditional generators or as a replacement thereof. Germany’s GIZ, a government agency that works in international cooperation and capacity-building, has already published a feasibility study for such solar applications together with counterparts in India.
A Double Dividend
The defense industry should take a closer look at sustainable solutions and carve out future market shares for technologies that pay a double dividend to security, both directly through their application and indirectly through avoiding negative ripple effects to the environment and health. Increased public spending on green defense would not only help modernize militaries, but also help countries meet their NATO obligations for military expenditures.
Governmental research programs should further incentivize the development and roll-out of sustainable and energy efficient defense technologies, reaping lower-hanging fruits such as the replacement of generators. This exercise of foresight could help build a strategic advantage for national defense.
Kira Vinke leads the Center for Climate and Foreign Policy at the German Council on Foreign Relations (DGAP).
