Hydrogen Fuel - Is It For You?

"Run your car on water". "Clean the air as you drive". "Do it yourself, it's cheap and easy". More than likely, you've heard these claims discussed in conversations, posted on the web, or seen them in magazine ads. If not, let Diesel Power be the first to tell you that yes, water has the potential to help power your diesel vehicle. The question becomes: is hydrogen for you, and at what cost?

Hydrogen Basics
Hydrogen is the lightest, simplest (contains only one proton), most abundant gas in the universe. It is the fuel of choice for our sun, so calling hydrogen an alternative energy source is a stretch. In the 1860s and 1870s, some of the first automobiles were powered by hydrogen, since gasoline was considered too dangerous. During World War I and II, fuel shortages drove engineers to create hydrogen-powered vehicles. Today, major automobile manufacturers are building hydrogen fuel cell cars, which consume stored hydrogen gas (H2) in a fuel cell in order to produce electricity for an electric motor. But, there are a few challenges with using stored H2 as a fuel.

First of all, hydrogen gas is not energy-dense by volume, so a hydrogen fuel tank has to be huge, or it has to store hydrogen under extremely high pressure (70,000 psi) in order to be as energy-dense as diesel fuel. According to a Department of Transportation report titled, "Guidelines For Use of Hydrogen Fuel in Commercial Vehicles: Final Report," "Gaseous hydrogen fuel with the same amount of energy as one gallon of diesel fuel would only weigh about one third as much, but would occupy almost seven times the volume if stored at 10,000 psi." Second, there is no hydrogen infrastructure to fuel hydrogen-powered vehicles. While there are more than 70,000 diesel fuel stations across the country, there are less than 70 places in North America to buy hydrogen for automobiles. Commercially made hydrogen is produced by stripping the carbon atoms out of compressed natural gas (CNG) using steam. This process, known as cracking, converts CNG, which has a chemical formula of CH4, into hydrogen gas. So, unless one gets their energy to make hydrogen gas from wind, solar, or geothermal sources, they might as well just skip a step and burn the CNG.

Making Hydrogen From Water
Electrolysis is the scientific word describing what happens when electricity breaks the molecular bonds that hold water together. At the atomic level, water contains two atoms of hydrogen and one atom of oxygen. When two volts of electricity are passed through water, hydrogen bubbles form on the negative side of the circuit (cathode) and oxygen bubbles appear at the positive side of the circuit (anode). Hydrogen does not like to be alone, so it joins with oxygen right as it leaves the cell. This new gas is called oxyhydrogen (HHO). In the automotive world, the terms oxyhydrogen (HHO) and hydrogen are often used interchangeably, even though they are not technically the same thing.