Energy Transition as an Operational Advantage for the Military


Energy Transition as an Operational Advantage for the Military

Energy transition is discussed worldwide on a daily basis. Many nations and industries are taking action and invest large sums to develop alternative energy solutions in an endeavour to reduce or abandon the use of fossil fuels. Except in the military. Very often, energy transition for defence seems to be a non-issue based on the assumption that any energy source needed will always be available for the military in wartime conditions. Also, the amount of pollution in wartime is not considered relevant.  Now and in the near future, European military forces are procuring new capabilities with a forecasted lifespan of 30-40 years after delivery, while development and production may take up to 10 years. This means we are now taking technical decisions about systems that are intended to be in-service until 2060 – 2070. As the first relevant factor, by that time fossil fuels may have become very scarce worldwide. An official claim to get fuel will not change that. This does not mean we have to implement fuel technology of the 2050’s right now, but we need to prepare capabilities for important changes in their sources of power, taking into account future equipment programs and future facilities, permanent and non-permanent. Built-in fuel flexibility is a necessity for systems that last.

A second relevant factor is the immense amounts of new energy technology that is being developed in Europe and elsewhere to support the worldwide energy transition. Many of these technologies are very promising and provide options to save energy and/or to replace fossil fuels for other power sources. Using energy-saving technologies could reduce the logistic footprint of our forces drastically. It could also reduce the current cost and effort to transport huge quantities of high standard fuels to mission areas. Cost of transportation not only in terms of money but also in the loss of lives during transport in risk areas. Hence, applying new sources of energy could bring our forces a logistic and operational advantage. Most of the technologies being developed worldwide focus on changes of power sources from fossil to electrical. In the next decades, we will see the improvement of natural gas and LNG, renewable power, biofuels, (powdered) hydrogen or other alternative sources of energy. Even small-scale nuclear plants could be an option when (NATO) standard fossil fuels are less or not available anymore. And using aerostats for producing electricity with photovoltaic solar platforms is a possible option in support of forward operational bases. Many more options will become available in the near and more distant future. Due to the nature of activities in energy transition, most of these are focussed on the short to medium term and may be outdated by 2040 or beyond. Consequently, it will be necessary to develop effective new technologies for major defence capabilities that will be used until 2060 and beyond.

Land forces

Electrical energy storage: Wind energy and solar power are attractive sources of power for out-of-area military bases. Important downside is the lack of energy storage solutions needed for reliable and effective operations on a 24/7 bases. When electrical energy could be stored for a reasonable period of continuous operation (depend on application and location) wind- and solar power can be used. A lot of development work is being done throughout the EU and beyond. An example of a military safe and reliable storage system suitable for use in army compounds has been developed in Norway by the company Energy Nest. Their thermal batteries store vast amounts of energy in concrete and steel.

Electrical energy smart GRID: For large long-stay military compounds the use of high voltage grids could be considered. These grids enable sharing of energy between multiple systems and using surplus amounts of energy at the time it becomes available. An example is to start laundry machines at sunrise when solar panel energy comes on-line and pause these systems at peak times of high kitchen and air conditioning demand. However, there are considerable costs involved and certified personnel is required to operate high voltage grids. The Netherlands Army is cooperating with 250 SMEs and other companies to develop smart solutions for future compounds in their “Field Lab Smart Base”. Smart grid solutions are among the innovations pursued.

Electrical vehicles: Widespread civilian use of electric vehicles will lead to developments with obvious military application. The difficulty for the military will be the recharging of vehicles in combat conditions. Further, without considerable improvements in the energy density of batteries, the weight of batteries and the need to protect them in an armoured vehicle will restrict their military application perhaps to rear area logistic vehicles. Hybrids are a more likely option but batteries (albeit fewer of them) will still be required along with the resupply of fuel for the hybrid engine. Developments in civilian vehicles will solve this dilemma in the next decade and by 2030 also military vehicles will be able to use battery power. It is necessary to ensure that new vehicles with an intended lifespan of 15 years or more are designed in a way that they can be retrofitted with battery packs and electrical engines.

Vehicle Design: A number of developments are being made in the design of new military vehicles, which should have a beneficial effect on logistic demands and, indirectly, the environment. Lighter vehicles are in development largely as a result of the use of improved armour materials such as ceramics, nanotechnology solutions etc. which offer more protection at lighter weight. As in civilian applications, the use of more fuel-efficient conventional engines for military vehicles will continue. Indeed, most engines used in military vehicles (even in tanks) are versions of civilian engines; a notable exception is the gas turbine engine in the US Abrams tank – it is derived from an aero engine and has very high fuel consumption. Increased automation, more widespread use of autoloaders and other developments. will allow reductions in crew size which should allow for smaller vehicles with improved fuel consumption as a consequence. Unmanned vehicles may not need armour at all. Their reduced weight also implies less fuel consumption. This is relevant for use of fossil fuel, but also for any other source of energy. Better reliability of combat vehicles should enable a reduction in the provision of battlefield repair and recovery resources which, otherwise, require their own refuelling and resupply effort. There have always been arguments in the military as to a preference for wheels or tracks for armoured vehicles. If developments for wheeled vehicles could offer the same, guaranteed, cross country performance as for tracked vehicles then advantage could be taken of the better fuel economy that, generally, wheeled vehicles have to offer.

More Efficient Fleet Management: In intense combat involving sizeable military formations it is common practice for higher command to resupply crews, units and formations on a daily, default quantity, basis. This is based on the assumed quantity of ammunition, fuel and rations that will have been consumed the day before by a unit involved in a specified level of operational activity. Unit and formation commanders can request more if consumption has been particularly high: they are less likely to request less. As a consequence, there is sometimes significant waste of some commodities; in the heat of battle crews and units are not motivated, understandably, to worry about it or to try to return unused supplies. Further, in the heat of battle, vehicle crews and their units do not welcome the burden of reporting what they have consumed, nor do they have an efficient means of doing so. A significant future development is likely to be the automatic reporting to higher authority, by the vehicles themselves from on board sensors and communication systems, of actual fuel and ammunition consumption. This should lead to much more efficient management of resupply. Such systems already exist on a small scale and have been proven but are likely to be much more widely adopted by the military in future.


It is difficult, currently, to envisage the effective use of alternative energy sources for military combat aircraft. Future designs will benefit from the developments in reliability, fuel consumption, efficiency etc. of civilian aircraft engines and Air Forces will continue to rely on military versions of civilian aircraft and helicopters e.g. A400M, for logistic support. In this area the energy transition will largely follow civilian developments. An energy transition policy in military aviation that could lead to an operational advantage is the use of alternative platforms. For example, unmanned aircraft like drones would be smaller and thus at least less fuel demanding. In many cases drones also have a much longer endurance that opens up new or improved military use. In addition, other EASA or military safety regulations apply for unmanned aircraft. A practical example is the idea of the Netherlands Air Force to develop a “Cargoleaper”. This is a huge autonomous multicopter capable to transport 20 ft containers of up to 5000 kg over 250 km. Although this aircraft in itself may use quite a lot of fuel, it saves a huge number of vehicles and helicopters needed to secure manned logistic ground transport. When available, this type of medium range cargo transport in adverse areas could or would have many applications for civilian purposes too. I.e. for NGOs and disaster relief. Solar powered electric flight could be stimulated for military applications based on scientific test flights like the Solar Impulse and others. A promising military application would be High Altitude Long Endurance (HALE) or High Altitude Pseudo Satellite (HAPS) UAVs for reconnaissance, surveillance and intelligence gathering (ISTAR) duties. Worldwide several companies are working on this technology, including Airbus/Qinetic in Europe.

Naval Forces

Major naval vessels use large quantities of energy for their propulsion and household consumption. As already noted, some warship and submarines are already nuclear powered. Most new, non nuclear designs involve the use of fossil fuel engines. These fossil fuel engines usually generate electrical power for use by electric motors which provide the main propulsion. The sheer size of ships compared to land vehicles means that space is available for designers to consider most alternative fuels options and navies will seek to reduce consumption wherever possible to save money, indirectly, be of benefit to the environment. Again, they will also benefit from relevant developments in the civilian marine industry. A complicating issue is that currently new major naval ships and submarines are being developed and build that will remain in use until 2060 or beyond. By that time standard F76 NATO fuel may not be on the market any more. Almost certainly it will not be as easily available as it is now. For that reason, it is important to add fuel flexibility to naval shipbuilding requirement. Fossil fuel gasturbines or diesel engines should not only be able to run on NATO standard F76, but flexible to use any fuel, ranging from sulphurised fossil diesel to 100% biodiesel. Additionally, the design of major naval ships should be flexible and modular to accommodate replacement of fossil fuel engines with other means of electrical power generation that could become available in the next 20-30 years. Using a Integrated Full Electric Propulsion (IFEP) design for major naval vessels is an important first step to accommodate the energy transition for this type of military application. When safe and reliable hydrogen fuel cell technology becomes available, or small nuclear power plants, both as described above, these could then be retrofitted into these existing ships. Naval ships like mine-hunters and patrol boats often travel on slow speeds for quite some time. These could benefit from rapid developments in battery technology and use hybrid propulsion. When developing new ships in these categories weight and space for future batteries for hybrid operation should be included. Like in army compounds a local area smart grid could be of interest for these ships too. Small submarines typically travel for up to one week in regional waters. Research by Delft University (NL) indicates that these types of submarine could run on Li-Ion batteries only. This could be suitable for the navies of Norway, Sweden, Germany, Baltics, Mediterranean, etc.


Several interesting future options for future technologies are visible now, but the technical focus of industry is merely on the short to  midterm. As major capabilities with a lifespan until 2060 and beyond are being developed now it is necessary to ensure future technologies can be retrofitted when availability of fossil fuel recedes. Technological developments in civil energy transition should be monitored for future use in military capabilities. In particular reliable and safe electrical energy generation and storage. These developments typically occur in SME companies throughout Europe not primarily focussed on the defence market. Some technologies of interest for military capabilities are not expected to be the focus of civil developments. R&D and product development using these technologies could be stimulated for future use in military systems. Examples are Hydrogen fuel cells, small nuclear plants, solar power for HALE UAVs and local area smart grid.



This is an excerpt of the report ” Energy Transition as an Operational Advantage for the Military”, by a working group of the Federation of European Defence Technology Associations (EDTA) and EuroDefense (19.02.2019): 

Federation of European Defence Technology Associations

The Federation of European Defence Technology Associations (EDTA) is a federation of 11 Member-Associations in 10 European Nations. Each dedicated to Defence and Security Technology development and innovation. The membership in the federation adds up to over 6000 individual and 400 corporate members. EDTA was established in 1992 upon initiative of the Independent European Programme Group (IEPG), a forum for armaments cooperation established in 1976 by Defence Ministers of the European NATO nations.