As war rages in Ukraine, leaders of the world’s largest military alliance convened in Madrid on Tuesday for what NATO Secretary-General Jens Stoltenberg said he envisions as a “transformative” summit, aimed at making the pact “even stronger and more agile.”

On the agenda of the three-day meeting: Integrating climate change into NATO’s statement of purpose for the first time, and setting out a roadmap for how the heavily fossil fuel-reliant militaries in the alliance can reduce their massive greenhouse gas footprints.

NATO announced its climate plan a year ago, and some observers thought it might be pushed aside at the Madrid summit by the urgency of how to support Ukraine in the face of Russian President Vladimir Putin’s aggression. But the war—fueled by Russia’s oil and gas revenue and with global impacts on food supply and economies—appears to have created new motivation within the alliance to address the security risks of both climate change and fossil-fuel dependence.

“Russia’s war in Ukraine underscores the urgency of acting today to reduce Putin’s weaponization of fossil energy on the West,” said Sherri Goodman, who served as U.S. deputy undersecretary of defense during the Clinton administration. 

Goodman made the remarks earlier this month when an expert group she leads, the International Military Council on Climate and Security, released a roadmap for decarbonizing defense in advance of the NATO summit.

“While some say that the war and the provision of military aid to Ukraine makes it harder to decarbonize defense, in fact, the opposite is true,” said Goodman. “Russia’s invasion, along with the associated global energy and food insecurity it has generated, means we need to accelerate the energy transition and enable militaries to lead by example.”

Dependence on fossil fuels has proven to be a battlefield liability as well, with Russia’s advance stalled partly by fuel shortages and thousands of U.S. soldiers killed or wounded during the wars in Iraq and Afghanistan in attacks on fuel and water resupplies. 

But it is not easy, either politically or as a practical matter, to reduce the greenhouse gas emissions of armed forces, when military strength has long been defined in terms of the ability to deploy jets, tanks and other equipment that burn copious amounts of fuel.

NATO is expected to adopt emissions reduction targets for its own 4,000-person headquarters in Brussels and command centers around the world. But it will be up to the governments of each of its 30 member nations to decide what goals to set for decarbonization of their armed forces. Some are more prepared than others to take such steps, and all are aware that potential foes—particularly Russia and China— have no plans to reduce their military reliance on petroleum.

One of the greatest challenges is that few countries know the baseline for their military’s greenhouse gas emissions well enough to set goals to reduce them. Even those that do record and report their military emissions, like the United States and Canada, do not count the carbon pollution produced by military suppliers in the private sector. Nor do they capture some of the largest greenhouse gas impacts of their activities: those that accompany the destruction of war. 

A community of academics studying the environmental impact of armed forces has been pushing for nations to get a better handle on the greenhouse gas impact of militaries. They argue that it is doubtful the world can achieve the decarbonization goals set in the Paris agreement without an energy transformation in defense operations.

“Nobody is suggesting that we constrain military operations through carbon budgets,” said Doug Weir, research and policy director of the United Kingdom-based nonprofit Conflict and Environment Observatory, which just released a proposed framework for military emissions reporting. “But it’s more a case that militaries are so fundamentally locked into fossil fuels—and high-consuming fossil fuels—that there’s just not really been much of a pressure on them until recently to actually improve the energy efficiency of their platforms.”

He added, “There’s got to be decades of progress in actually decarbonizing the military and reducing their consumption and dependency, and given the long lifetime of most military equipment, these are conversations that need to start.”

The Defense Department Has ‘No Choice’ But to Focus on Climate

The attention that NATO nations are now giving to climate change marks a sharp turnaround from 25 years ago, when the United States lobbied hard to ensure that the Kyoto protocol would contain a national security exemption that would free nations from any obligation to limit the greenhouse gas emissions of military operations. 

“We are concerned that emissions limitations, if not properly addressed, could prevent rapid decisions about training and employing multilateral peacekeeping and peace enforcing forces,” said a 1997 State Department memorandum on the U.S. position, recently released in response to an open records request by the nonprofit National Security Archive. 

The United States never ratified the Kyoto protocol, but the impact of the national security exemption it obtained has been long-lasting, say academics who have studied military carbon emissions. For the industrialized nations required to report their annual greenhouse gas emissions under the United Nations Framework Convention on Climate Change, it has been voluntary whether to separate out military emissions. Some countries make estimates, while others report no military emissions at all.

The U.S. Department of Defense, however, has been reporting its greenhouse gas emissions from fuel use and electricity since 2010, under a policy instituted by President Barack Obama for all federal agencies. Even under President Donald Trump, who sought to aggressively roll back government climate policy, agencies continued to track carbon emissions; the Defense Department recently produced a Congressionally-mandated report compiling its emissions data for the past decade.

DOD emissions have fallen 40 percent since 2010, reflecting the drop-off from the height of troop deployment in Iraq and Afghanistan. But the military’s carbon footprint is still as large as that of a small country, at nearly 52 million metric tons of carbon dioxide in fiscal year 2020, accounting for 75 percent of U.S. government greenhouse gas emissions, according to the U.S. Department of Energy. A study by Neta Crawford of Oxford University, who has a book coming out this fall on the Pentagon and climate change, showed that from 2001 to 2017, the U.S. military emitted more than 440 million metric tons of greenhouse gases directly related to war-related fuel consumption—the equivalent of adding nearly 95 million passenger vehicles to the road for a year.

That’s why there was initially an outcry from climate activists and Democratic members of Congress in December over President Joe Biden’s executive order seeking large cuts in greenhouse gas emissions across the federal government. The order included a provision allowing agencies to seek a national security exemption, offering a loophole for the government’s largest carbon polluter.

But Defense Department officials said they don’t plan to seek a national security exemption and are committed to the objectives in Biden’s executive order, which include reaching 100 percent carbon-free electricity by 2030, and charting a path to net zero emissions by 2050. In a speech this spring, Deputy Secretary of Defense Kathleen Hicks said that the department would be making “energy supportability and demand reduction” a priority in upgrades to current programs or the development of new capabilities.

One by one, branches of the armed forces are releasing detailed plans to reduce carbon emissions, starting with the Army in February and the Navy in May. The Army plans, for example, for all of its light-duty non-tactical vehicles to be electric by 2027, and to install a microgrid on every installation by 2035. The Navy aims to deploy nature-based solutions to mitigate shoreline erosion while protecting its coastal mission-critical facilities, and has a goal of diverting at least half of its non-hazardous solid waste from landfills by 2025. 

“The Department of Defense has focused on climate at this time because we have no choice,” said Richard Kidd, deputy assistant defense secretary for environment and energy resilience, in an interview. “Climate change is the context in which all of us are going to live our lives and perform our jobs. And for the Department of Defense, we will look at both climate adaptation, which is managing the unavoidable, and climate mitigation, which is avoiding the unmanageable.”

At the same time the United States, the largest NATO member, has been forging a new greenhouse gas strategy for its military, NATO has been moving to ratchet up its policy on climate change. Clean energy is not an entirely new subject for the alliance; NATO adopted a “Green Defence” framework in 2014, pledging to significantly increase the energy efficiency of its forces. But addressing climate change necessarily fell to the back burner for NATO during the Trump administration, which disputed not only the science of climate change but the purpose of the 70-year-old collective defense alliance among the United States, Canada and Europe.

But last year, at the first NATO summit attended by Biden, the alliance issued a Climate Change and Security Action Plan declaring climate change “one of the defining challenges of our times.” Stoltenberg, the former prime minister of Norway who once served as United Nations special envoy for climate change, became the first NATO secretary general to attend international climate talks last fall. At a side event in Glasgow, he said that climate change “is now at the heart of NATO’s agenda.”

Several of the initiatives NATO announced in 2021 will come to fruition at the Madrid summit. Substantial language on climate change will be included in NATO’s new “Strategic Concept” document, the first update in the alliance’s statement of purpose in a dozen years. NATO also plans to release an analysis of the security implications of climate change for the alliance, as well as measures for how NATO and its forces will aim to adapt. This will cover everything from readying forces for more disaster relief, equipping them for more extreme temperatures, and responding to the reshaping of the Arctic due to melting sea ice.

NATO will announce goals for greenhouse gas reduction targets for the NATO organization for 2030, with an eye to net-zero emissions by 2050. NATO also will release a long-awaited analytical tool that allies can use to account for the greenhouse gas emissions from military activities and installations. But NATO, which does not have its own armed forces, is not setting goals for the militaries of its member states, which generate the bulk of greenhouse gas emissions associated with NATO operations. As an intergovernmental body, NATO’s view is that it has no power to enforce such measures, which are under the purview of national governments. And in any case, such an approach would be a political non-starter as NATO members focus on the response to Russia’s invasion of Ukraine. 

“It is one thing to seek reductions for your routine activities and bases at home,” said James Appathurai, NATO’s deputy assistant secretary general for emerging security challenges. “It is a very different thing to seek reductions for deployed forces and in exercises when the security environment is getting worse.”

Not Just Climate: Fossil-Fuel Dependence Is a Battleground Lability

Already, it is clear that response to the Russia-Ukraine conflict will complicate any effort to decarbonize NATO armed forces to some extent. Germany has pledged to spend 100 billion euros, about $105 billion, to modernize its armed forces, nearly tripling its spending from last year. That money is expected to go into the purchase of heavy transport helicopters, fighter jets and armored vehicles, all of which are prodigious consumers of fuel.

At the same time, military strategists are aware that dependence on petroleum fuel on the battlefield is a major vulnerability. During the fighting in Ukraine, fuel shortages helped to stall the advance of Russian convoys on Kiev. During the United States’ fighting in Afghanistan and Iraq, 3,000 U.S. soldiers were killed or wounded in attacks on fuel and water resupplies between 2003 and 2007, about one casualty for every 24 fuel convoys. During the troop surge in 2011, the United States tried to avoid convoys by parachuting barrels of fuel to remote bases, at a reported cost of as much as $400 a gallon.

Kidd said the U.S. also found it was able to reduce the number of fuel convoys with experimental solar microgrids it deployed to provide electricity at remote bases in Afghanistan which otherwise would have relied on diesel generators. He says the military sees microgrids, large-scale battery storage, and solar panels as investments in cleaner energy that also make bases more resilient and align with the defense mission.

For tactical vehicles and aircraft, the challenge is more difficult. The Navy has had some success experimenting with biofuels as a drop-in replacement for jet fuel, but obtaining enough supply at an affordable price is a problem. The Department of Defense is currently financing startup company efforts to produce military-grade biofuels from algae and agricultural or woody waste material, like food scraps or crop stalks. 

Also, the Army is studying electrification kits that it can add to tactical vehicles, reducing fuel consumption by 25 percent. Currently, Army tanks and other tactical vehicles must continuously run their engines to power auxiliary systems like communications, even when the vehicles aren’t moving. Electrification kits will allow the vehicles to have power without idling.

Yet there is recognition throughout the military establishment that the technology currently doesn’t exist to deploy tactical troops and weapons without fossil fuel. In addition to the research and development that the U.S. military is doing, NATO is establishing a multinational Innovation Fund, the world’s first multi-sovereign venture capital fund. Its purpose is to invest 1 billion euros in early-stage startups and technology aligned with its strategic objectives, including addressing climate change and reducing greenhouse gases.

As Society Breaks Away From Fossil Fuels, the Military Must Follow Suit

Those who have studied the problem of military greenhouse gas emissions, from both inside and outside the military establishment, agree there are no easy solutions. In the view of some, the only way to significantly cut carbon pollution from the military is to reduce spending on the military.

“We need a recognition of the challenges ahead, and that it might not necessarily all be answered by switching technologies,” said Linsey Cottrell, environmental policy coordinator at the Conflict and Environment Observatory. “There have to be some military strategy decisions as well, decisions on deployment and capacity building. As expected military expenditures increase, obviously there’s this risk that there are just going to be increases in greenhouse gas emissions as well.”

But NATO nations, for now, are trying to increase their military expenditures while simultaneously figuring out how to field fighting forces without fossil fuels.

“If our whole society is moving away from fossil fuels in let’s say, 20 to 30 years, the infrastructure for fossil fuels will also diminish,” said David van Weel, NATO assistant secretary general for emerging security challenges.

He added, “If the military are then the only ones using fossil fuels, then we will need to do our own exploration, our own refineries, our own logistics of the whole of the fuel chain, and that can not be reality.”

And since the systems that armed forces are procuring over the next 10 years are meant to last for 30 years, he said, “We need to think about innovative solutions to move away from fossil fuels now.”