One advantage of corn ethanol is that it burns hotter than gasoline. Although this is good for engine efficiency, corn ethanol has lower energy content. This means that it takes more corn ethanol fuel to produce the same amount of power compared to angines using gasoline. Other disadvantages relate to the energy needed to grow the corn, transport it to the refinery plant and process it into ethanol. The entire process is very energy-intensive and wasteful. Moreover, growing corn for the ethanol market uses up valuable agricultural land. Despite these drawbacks, corn ethanol fuel has become very popular. The U.S. government has encouraged farmers to sell their corn to biofuel refineries, which has caused prices to rise substantially-much more than any other biofuel source and more than selling corn for animal feed.