Germany's largest arms manufacturer Rheinmetall has entered into a strategic partnership with synthetic fuel producer INERATEC to scale up e-fuel production, calling the technology "essential for modern defence".

"Synthetic e-fuels are the only scalable solution that matches the energy density, storability and versatility of conventional fuels," the company said in a press release. E-fuels are produced using electricity, water and carbon dioxide, and can be used in sectors where electrification is difficult to achieve, such as aviation or shipping; they are expensive, available only in small quantities and require a great deal of renewable electricity.

Rheinmetall argues that a resilient energy supply is essential to defence, and that e-fuel is a dependable fuel source that is not reliant on others, since it can be produced locally using wind turbines or solar panels. The fuel would allow armed forces to cut greenhouse gas emissions without modifying existing military vehicles, including tanks and aircraft.

"As fossil fuel supply chains become increasingly vulnerable in the event of conflict, the ability to produce CO₂-neutral synthetic fuels locally is extremely important," Rheinmetall notes. The partnership aims to speed up the construction of e-fuel production plants. "As a first step, Rheinmetall and INERATEC are looking for suitable sites for their plants, preferably close to military infrastructure or existing pipeline systems," reports Süddeutsche Zeitung. "This collaboration is a turning point in the development of resilient energy systems that operate independently of fossil fuel supply chains and vulnerable infrastructure"

Germany, like most European countries, is rapidly increasing military spending in response to Russia's 2022 invasion of Ukraine and shifts in the geopolitical situation. Ahead of approval in parliament, the German government adopted a reform package that effectively removes national spending limits on defence in order to strengthen the role of the Bundeswehr in European and NATO security infrastructure.