WASHINGTON — A lead senator on the Armed Services Committee is introducing legislation to strengthen emissions reduction targets at the world’s largest institutional consumer of fossil fuels: the Defense Department.

Sen. Tammy Duckworth, D-Ill., introduced the Depend on Domestic (DOD) Clean Energy Act on Thursday to set Pentagon targets for reducing emissions while providing greater funding flexibility to achieve those goals.

Duckworth, who chairs the Senate’s air and land defense panel, has introduced the bill as stand-alone legislation, but she told Defense News she’d like to see it included in the annual defense authorization bill the Armed Services Committee is scheduled to mark up next month.

“The [Defense Department] actually is very progressive on this,” said Duckworth. “Back in the [Barack] Obama administration, Secretary of the Navy Ray Mabus actually did an entire naval training exercise using all biofuels. Every ship, every aircraft, every vehicle ran on biofuel and demonstrated that it would be possible.”

Her bill would require the Defense Department make at least 40% of its electricity generation carbon pollution free by 2024 and increase that goal to 100% by 2030. It would also set a target of reducing emissions from Defense Department installations by 20% by 2024 with an ultimate goal of net-zero emissions by 2045.

The bill would push the Defense Department to continue investing in alternatively fueled vehicles by setting a 100% zero emission target for non-tactical vehicle acquisitions by 2035 and the same goal for tactical vehicles by 2045.

Duckworth, an Iraq war veteran, noted 50% of U.S. casualties in that conflict occurred during attacks on convoys. “And 80% of all convoys were driving diesel fuel,” she said.

To help reach these targets, the bill would allow the Pentagon to use unobligated funding beyond the end of the fiscal year for the Environmental Resilience and Conservation Investment Program.

“This is going to basically give them additional flexibility and the authorities needed so that they can use those funds to do things like upgrading energy management systems and the like,” said Duckworth.

President Joe Biden has set a nationwide goal of achieving net-zero greenhouse gas emissions by 2050, though congressional Republicans have opposed additional funding for green energy investments.

Still, Duckworth said she’s optimistic Republicans won’t oppose her legislation given the Defense Department’s support for moving to clean energy.

“My Republican colleagues tend to want to support the [Department of Defense],” said Duckworth. “This is not something the [Department of Defense] is fighting. This is something that they want to do.”

The Defense Department released its climate strategy in October. And the Army plans to install a microgrid on all its installations by 2035 and field fully electric tactical vehicles by 2050 — goals that align the Pentagon with Duckworth’s legislation.

The Pentagon started incorporating climate analysis into its wargaming last year after identifying the risks posed by climate change in its 2018 National Defense Strategy.

Meanwhile, the Marine Corps announced earlier this week it is considering moving some of its bases, including South Carolina’s Parris Island, to other locations due to extreme weather requests stemming from climate change.

Bryant Harris is the Congress reporter for Defense News. He has covered U.S. foreign policy, national security, international affairs and politics in Washington since 2014. He has also written for Foreign Policy, Al-Monitor, Al Jazeera English and IPS News.

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