By Corinna Wu
Alternative energy is hitting the headlines. Last year, former Vice President Al Gore scored a surprise hit with his climate-change documentary An Inconvenient Truth. Currently, drivers are steeling themselves against gasoline prices that could shoot well past $3 per gallon. The war in Iraq continues to draw attention to the United States’ dependence on imported oil and has prompted calls for a shift toward domestic sources of fuel.
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More and more, policy makers are touting a homegrown solution—literally—to the nation’s energy and global warming problems: ethanol made from plants. Mixing ethanol into gasoline reduces overall greenhouse-gas emissions from vehicles because plants recycle carbon: The fuel that they yield produces carbon dioxide, just as fossil fuels do, but the plants consume carbon as they grow. And because ethanol molecules contain oxygen, their presence makes gasoline burn more completely, reducing carbon monoxide and other harmful tailpipe emissions.