The use of renewable energy sources will decrease the Army's fossil fuel consumption, while lowering greenhouse gas emissions and creating a more assured energy supply.

WHITEHOUSE: Energy and Environment Latest News | The White House

Study after study has pegged energy efficiency as the lowest-cost way to curb fossil-fuel consumption and the resulting greenhouse-gas emissions.

WSJ: The Experts: What Will Be the Next Technological Breakthrough in Energy?

Presently, natural gas used as transportation fuel constitutes only about 0.1 % of total U.S. consumption.

FORBES: Tough Trucking For Natural Gas Vehicles: Can They Make It In The Long Haul?