Combating climate change: How the US military is going green

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The U.S. military’s green energy efforts have continued apace despite the fracking boom and rapid rise in domestic oil production in the United States.


  • The U.S. military is the world’s single largest oil consumer, and is working to source 25% of its energy needs from renewables by 2025.
  • From portable batteries and solar cells, to electric vehicles, biofuels, and microgrids, the Pentagon is spending billions to make make the military greener.
  • The military’s green push is helping veterans acquire marketable skills and transition to jobs in the clean tech sector.

If we told you that the U.S. military is green, you’d probably think we’re talking about the latest camouflage pattern, or maybe those plastic toy soldiers, but we’re actually referring to the surprising ways America’s armed forces are tackling climate change.

Unbeknownst to many, the U.S. military has declared war on emissions, and has made clean energy adoption an important part of its strategy for climate resiliency and combat effectiveness.

Threats to supply chains have laid low many armies over the millennia, and U.S. commanders have long been aware of the logistical risks associated with fossil fuel reliance. During the Iraq War, fuel convoy duty was one of the deadliest assignments in the conflict, with 3,000 contractors killed or injured between 2003 and 2007.

And weeks before the invasion of Baghdad, General James Mattis called on the Department of Defense (DoD) to “unleash us from the tether of fuel.”

Military leading the charge in energy transition

The Pentagon uses the most fuel of any single organization on Earth (56 million liters each day in 2016), equivalent to 2% of U.S. fossil fuel production and 1% of U.S. emissions.

In fact, the DoD accounts for more than 75% of federal government energy use, fifteen times more than the next largest energy consumer, the Post Office. Recognizing the costs and vulnerabilities of fossil fuel use, the U.S. military has accelerated its transition to renewables, especially since the mid-2000s.

In 2007, President George W. Bush signed a law mandating that domestic military facilities had to produce or procure no less than 25% of their energy from renewable resources by 2025.

In 2012, the Pentagon committed to developing 3GW of renewable energy capacity by 2025. The military’s renewable energy generation increased by almost 100% between 2011 and 2015, compared to a national average of just 2.6% during the same period.

The number of renewable energy projects in the military almost tripled to 1,390 between 2011 and 2015. And through the Army Net-Zero Initiative, the Army is aiming to establish 25 net-zero installations by 2030.

Sherri Goodman, Senior Fellow at the Wilson Center’s Environmental Change and Security Program (and former deputy under-secretary of defense for environmental security under Obama) explains that, “what [the DoD] does and how it uses its energy, how it reduces its emissions, makes its bases more resilient to climate change – that helps all Americans learn by example.”

Lean green fighting machine

During his tenure as Navy Secretary (2009-2017), Ray Mabus was a key proponent for green energy adoption, ordering the Navy to meet 50% of its onshore and afloat energy needs from renewables by 2020.

The Navy’s onshore facilities hit this goal five years early, with renewable energy now accounting for 66% of onshore needs. 1.2GW of wind and solar energy are now powering U.S. naval bases, with lifetime savings of $400 million due to lower fuel costs.

“[Adopting renewables] gives us an edge tactically, it gives us an edge strategically. It keeps […] fuel from being used as a weapon against us,” explains Maybus.

While the 2020 goals for afloat assets were not met, the Navy’s vessels have still undertaken substantial steps to reduce their reliance on fossil fuels.

In 2012, the Navy proposed the idea of a carrier strike force entirely powered by renewable energy, a force which set sail for the first time in 2016, despite a 70% drop in oil prices during the same time. At sea 40% of energy came from renewable resources by the time Mabus left office in 2017.

During that time, the Navy cut its overall oil consumption by 15%, and the U.S. Marine Corp has gone even further, slashing oil use by an impressive 60% during the same period.

Half of America’s 3,500 military bases globally are at risk to the effects of climate change.

During his tenure, Maybus ordered refitting ships to upgrade their lighting to high efficiency alternatives, while battery miniaturization has helped reduce the weight carried by infantry from 5.9kg to 4.1kg.

And rollable solar panels means that a Marine company no longer has to carry more than 300kg worth of batteries to power its equipment. SEAL teams are also using renewable energy tech to stay out in the field longer and reduce the number of resupply missions.

Other developments include the DoD researching algae-based jet fuel, while defense contractor Lockheed Martin is developing Ocean Thermal Energy Conversion technology (using temperature differentials in seawater to generate power).

Overall, the DoD spends $1.6 billion each year on energy research and development, including $400 million over five years on moveable, vehicle transportable, very small nuclear reactors.

Efforts are also underway to electrify the military’s tactical and combat vehicle fleets – a move that offers several benefits including; silent operation, enhanced stealth, fewer moving parts, modular design (and thus easier replacement and repair), longer service times, and increased range.

In a statement by U.S. Army Futures Command, fleet electrification could “[…] potentially reduce the Army’s logistical burden by nearly half when fully implemented.”

Using microgrids and behind-the-meter generation to fight future threats

The risk of power outages from natural disasters or attacks has motivated the military to increase base resilience by boosting on-site renewable generation. The ability to remove military facilities from the wider grid reduces the fallout from cyber and physical attacks against infrastructure.

To this end, the DoD is working on the Autonomous Energy Grids (AEG) program which consists of Network Optimized Distributed Energy Systems (NODES) that create a self-contained, smart energy community that can share energy resources but not suffer cascade failure if one or more NODES is attacked.

A January 2018 report by the DoD found that half of America’s 3,500 military bases globally are at risk to the effects of climate change.

Bases in Florida have suffered billions of dollars in damages from storms in recent years, and the Norfolk Shipyard in Virginia – the Navy’s largest and most comprehensive industrial facility – has been flooded nearly a dozen times in recent years due to rising sea levels.

In a strange turn of events, California held back many military bases in that state from increasing their share of renewables, as a law passed in 2015 capped the amount military installations could generate to 12MW and denied them revenue from selling to the grid.

Military officials noted that just seven bases in southern California could generate 7GW of solar, more than all residential solar in the state: the law was repealed in 2018.

In states like Ohio veterans make up 11% of the clean tech workforce, double the veteran representation in other industries.

In 2007, Nellis Air Force base in Nevada installed 14MW of solar capacity, then the largest project of its kind in the country.

More recently, Fort Campbell installed 5MW of solar to provide 10% of its energy needs in 2016, while Redstone Arsenal installed 10MW in 2018. 12% (15MW) of the energy for Fort Detrick in Maryland comes from solar, and the 640km² Fort Bragg began the construction of a floating solar microgrid in November 2020.

Texas’ Fort Hood – the largest base on U.S. soil – generated almost half of its energy from renewables in 2017, which will save more than $100 million over 30 years. Overall, 130MW of solar capacity has been installed at military facilities in almost 36 states between 2007 and 2021.

As the largest single oil consumer on the planet, the U.S. military is in a position to lead on the green energy front. The benefits from the Pentagon’s green offensive impact military spending, operational flexibility and global emissions.

Another added benefit of the military’s renewables push is that it provides service personnel with the training and skills in high demand due to the wider economy’s green shift.

Veterans are therefore better placed to find post-service employment thanks to the military’s green push.

This trend is already playing out in states like Ohio, where veterans make up 11% of the clean tech workforce, double the rate of veteran representation in other industries.

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Tomas van Stee

CEO & Founder

Tomas independently grew the company to its initial product market fit with $500k in revenue, and is now leading our rapidly growing team. He spends much of his time overseeing strategy and operations at EnPowered as we navigate many complex and heavily regulated markets. He graduated from the Richard Ivey School of Business at Western University with a Bachelor of Arts in Business Administration.