Fuel cells could break into mainstream use very soon, and that means big cuts in energy consumption. The US navy is reportedly ready to deploy generators powered by fuel cells. Meanwhile, a startup in Maryland claims it can offer a cheaper, longer lasting fuel cell than any on the market by next year.
There are several kinds of fuel cells, which work a lot like batteries (watch an explanation here). Some have been used experimentally in passenger buses in London, Beijing and other cities since 2006, and certain types of fuel cells are already sold as generators. But it's solid-oxide fuel cells, like the US military is now using, that have the most potential for energy efficiency. Until recently, their greatest strength--the high temperatures they operate at, which allow them to produce more energy than other fuel cells--had also made them expensive to produce. The materials needed to withstand over 1200 degrees Fahrenheit and proved costly and unreliable; most models couldn't last long enough to return their initial investment in energy cost savings.
But the short-term benefits of using less fuel (reducing the number of convoys needed to carry fuel around the battlefield reduces the number of vulnerable soldiers in the field) motivated the US Department of Defense Energy and Power Community of Interest, a collaboration between branches of the US military, to improve fuel cell technology for battlefield use. In its press release, the US military said it may use the technology to power naval war ships soon, too.