• Hydrogen cars present a few practical difficulties.yellow car, a honda japanese sport car model image by alma_sacra from Fotolia.com
  
  According to Hydrogen Fuel Cars Now online, "When hydrogen cars become the status quo, the U.S. can lessen its dependence upon foreign oil, achieve lower prices at the fuel pumps and cut down on the greenhouse gases that produce global warming." Despite their potential benefits, hydrogen-powered cars have a few disadvantages that have impacted their success.
  
  

Cost

• Hydrogen is a costly way to power cars. Most of the cost is generated by handling and storage. Additionally, standard gas stations and vehicles would have to radically alter their current equipment and practices to fit the needs of hydrogen-powered cars. Hydrogen production is also four times more expensive than gasoline, according to a UCLA online article called "The Hydrogen Highway."
  
  

Storage

• Storing hydrogen also presents difficulties. Unlike gasoline, pure hydrogen cannot be pumped into a gas tank, since it is a gas and lighter than air. According to a Columbia University online article, hydrogen can be stored in a pressurized gas tank, but the tanks would be very heavy and the hydrogen could potentially leak into the surrounding metal. It can also be stored as a liquid, but it evaporates quickly and would require expensive insulation to prevent excessive fuel loss.
  
  

Safety

• One of the primary reasons that hydrogen presents such difficulties for storage and transportation purposes is that it is highly explosive. According to Columbia University, it is one of "the most flammable substances on Earth." Nevertheless, various online sources claim that hydrogen is no more dangerous than other fuels if it is used appropriately.