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Houston, we have a problem. America's need for oil can't be satisfied by the supply coming out of Texas (or Oklahoma, or Alaska). And with nations like China and India undergoing rapid development, the world's supply of oil is increasingly strained. The need for more oil means higher prices and more pollution. You've probably felt the pinch at the pump already.
So what's the solution? In order to combat rising gas prices and decrease pollution, a number of new technologies have been developed. Fuel cell vehicles run on hydrogen and emit only water vapor. Biofuel vehicles run on fuel made from plant materials. Electric vehicles can run on rechargeable batteries, and hybrid vehicles use a combination of a gasoline engine and an alternative power plant.
You're probably familiar with gas/electric hybrids like the Toyota Prius. Though gas/electric hybrids are popular and offer a good way to increase fuel economy and cut back on pollution, they're not perfect (we'll talk about their shortcomings on the next page). Another hybrid option has been put forth and tested by a number of businesses, as well as the Environmental Protection Agency (EPA): hydraulic hybrids. Hydraulic hybrids use many of the same principles as electric hybrids, but instead of using potentially pollutive (and heavy) batteries, they use lightweight components and clean fluid to power the vehicle while it's at slow speeds.
Sound too good to the true? Read on to learn exactly how hydraulic hybrids work, how they compare to electric hybrids and how they're being used today.