Nearly 400 military members have signed a letter to the US Congress insisting research on alternative fuels for military use is vital to national security.
The letter aims to persuade Congress to drop plans to bar the navy from research on biofuels, or from buying fuels which cost more than traditional diesel or jet fuel.
It was signed by about 380 retired generals, admirals and other military officials.
The Pentagon has been investing in solar panels and wind turbines on bases for years, and testing energy saving measures on the battlefields of Afghanistan.
The Guardian reports that Republicans in Congress are demanding the navy scrap its research on biofuels, arguing the fuels are prohibitively expensive, and a diversion from more urgent security needs.
The veterans have countered that the research was critical to national security. "As a country, we must support efforts inside and outside the department of defence to reduce dependence on fossil fuels, deploy clean energy technology and move our nation toward energy independence," the letter said.
Military strategists have argued for a decade that fuel convoys in Iraq and Afghanistan exposed US forces to great risk from IEDs and ambushes.
The Pentagon has been working to green its bases and operations for a number of years, installing solar panels on wind turbines on bases, and testing energy saving measures on the battlefields of Afghanistan.
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