A Hydrogen Economy?

If we were to replace gasoline with hydrogen to fuel most of our cars, here is how it might work.48 Until nonfossil energy sources are available on a large scale, hydro­gen will be made from natural gas. Gas stations would be replaced by hydrogen stations to which natural gas will be delivered. Hydrogen would be generated locally and stored in underground tanks under pressure. Cars will have plastic tanks in their trunks to hold enough hydrogen for 200-300 miles. These tanks have to be under at least 300 atm pressure, but hose connections can safely handle the filling of the tanks. Hydrogen does not explode unless it is first mixed with oxygen. Inside the car, a fuel cell combines the hydrogen with oxygen from air to produce electricity. There is an electric motor, and the car then runs as an electric car, with H2O as the only emission. The fuel cell-electric motor combination is much more efficient than a gas engine, and less energy is used than if the natural gas or hydrogen is burned directly. Wind or solar power can produce electricity to use directly in the electric motor, but batteries need further development and in any case need a long time to charge. Hydrogen serves as a way to carry the energy. It is not burned directly in hydrogen cars. The main problems are the fuel cell, which is very expen­sive, and the sequestration of the CO2 if natural gas is used. Discussion of these subjects will follow. Right now it is not clear whether hydrogen cars or plug-in electrics will ultimately win out as the better solution for clean mobile power.