Can I convert my car to run on water?

A gas station in San Francisco shows a cost of more than $4 per gallon for regular gas on May 5, 2008. See pictures of alternative fuel vehicles.
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Every time you pull up to the pump at the gas station, it seems like you're in for yet another case of sticker shock. In the spring of 2008, the U.S. national average cost for regular unleaded gasoline set record highs for six straight days in May -- that's after it climbed 11 percent from April [source: CNN Money].

As a result of rapidly increasing energy costs, alternative fuels look more appealing with each record-breaking day. In his 2006 State of the Union address, President George W. Bush declared his intent to alleviate the United States' problem of being "addicted to oil" [source: White House]. He issued a challenge to replace 75 percent of America's oil use with alternative fuels by 2025.


­So which alternative fuel is the standout? There are plenty of contenders. Researchers are working feverishly to break through the challenges presented ­by each potential fuel source. For example, cellulosic ethanol has been shown to make a fine fuel, but the process of fermenting it from plants like switchgrass is expensive. Electricity can (and does) power cars, but hybrid vehicles still require gas to operate. And all-electric vehicles must be plugged into an electrical outlet to recharge the batteries after a couple hundred miles. What's more, most of the electricity used to juice up the car is being generated at power plants fueled by coal or natural gas, which emit pollutants.

It'll probably take a combination of all of these types of alternative energy to get America off its oil addiction. And it looks like hydrogen will play a major role as well. Hydrogen is the lightest and simplest element known to man, and it has a high energy yield. It's also all around us: Think water.

The technology is already in place to operate a car using hydrogen. So can you convert your car to run on water? Find out on the next page.


Water to Fuel Conversion

Can plain old tap water power your car? It's possible, but it may not be worth it.
Don Farrell/Getty Images

Believe it or not, the answer is a resounding yes. There are even conversion kits to help you. And some Web sites offer do-it-yourself guides that explain how to set up a hydrogen fuel cell for your car from common items you can find at any hardware store.

Whether you'd want to convert your car to run on water is another matter. The process of turning water into fuel is based in science, but whether or not it will improve your gas mileage (as these sites claim) is debatable.


Most conversion kits are based on a concept spread by Dr. Yul Brown, who extolled the virtues of extracting energy from plain old water. Dr. Brown used the process of electrolysis to separate water into its components -- two hydrogen molecules and one oxygen molecule. This mixture, called HHO (also known as Brown's gas), can be burned and the resulting energy used to power your car [source: Yul]. This fuel requires very little water and is meant to supplement the gas you use in your car [source: Run Your Car With].

Can plain old tap water power your car? It's possible, but it may not be worth it.


­So what's the problem? Like most other alternative fuel sources, HHO conversion kits for use onboard a car have a negative net energy ratio [source: du Plessis]. This means that the amount of energy you get out of the conversion is actually less than the amount you put in. Think about it like this: If it takes one gallon of gasoline to convert water into HHO, your energy output will equal one-half gallon of gasoline. You've just used one gallon of gas to produce the energy of one-half gallon. Speaking strictly in terms of energy, you would've been better off simply using that one gallon of gas to fuel your car. You would have gotten the benefit of the whole gallon, rather than just half of it.

There's another side effect of using hydrogen as fuel that auto researchers are still grappling with. Studies of hydrogen (which is a viable fuel) show it can cause brittleness and breakage in metal car engine parts [source: CEC].

But skepticism toward the water conversion kits available online and a little brittleness aren't stopping researchers from figuring out how to overcome the negative net energy ratio of exploiting hydrogen aboard vehicles. Some car companies have already created electric cars that run on hydrogen you pump into a gas tank at the service station.

What if a process could be developed to separate hydrogen from water without using more energy? That would be the Holy Grail. One group from Purdue University is hot on the trail. They've come up with a process to split hydrogen from water that requires little or no energy input. Adding water to a composite metal (alloy) made of aluminum and gallium separates water into its component molecules. The composite attracts oxygen, but not hydrogen, leaving the former element free and separated.

The Purdue researchers are still developing the technology, and it may be awhile before you find it under your hood. If you can't wait to run your car on water, you could always order a conversion kit in the meantime.

For more information on alternative fuels and other related topics, visit the next page.


Lots More Information

Related HowStuffWorks Articles

More Great Links

  • Cundiff, Rick. "Power companies' miserly cars beat gas-pump blues." Ocala Star-Banner. May 5, 2008.
  • Du Plessis, Mathew. "Idling on pure speculation." The Times (South Africa). May 9, 2008.
  • Fuel cell vehicles." California Energy Commission.
  • "Gas strikes 6th straight record high." CNN Money. May 13, 2008.
  • "Hydrogen generating technology closer than ever." Purdue University. August 29, 2007.
  • "President Bush delivers State of the Union address." The White House. January 31, 2006.
  • "Who was Yul Brown and why should you care?" Yul