Switch grass is one of the most efficient biofuels yet developed. It is a perennial
crop, meaning that it grows all year long. Normally, switch grass grows on the
prairies and can reach 2.2 meters tall. Through a refining process, switch grass is
turned into cellulosic ethanol which can be used in car engines. Some studies
show that biofuels using switch grass produce 540 percent more energy than
needed to grow, process and refine it. This is a very high “net energy yield,” much
better than corn ethanol. Currently, the technology used to convert switch grass
into ethanol is not as advanced as that for turning corn into ethanol. Fortunately,
switch grass is the one biofuel that does not adversely affect food prices. Both of
these biofuels are promising for the future.