Can You Really Run Your Car on Water?

What’s Up with Water Conversion Kits

First off, please keep in mind the words of dear old mom and dad: “There is no such thing as a free lunch.” Though we don’t have direct experience with a water conversion kit, our own experience with other types of fuel conversions has made us aware that there’s more than meets the eye here. Technically, the idea behind the “run your car on water” conversion kits is sound science, but the claims are very misleading.

Internal combustion engines cannot, and do not, run on straight water. These kits use hydrogen generators to electrolyze water that’s stored in a small tank under the vehicle’s hood. Basically, electrolyzed water (H20) is transformed into its constituent elemental parts, 2 atoms of hydrogen and 1 atom of oxygen (HHO)--commonly known as Brown’s gas. At this point, the gas is captured and piped into the engine’s intake manifold, where it mixes with the fuel (and this can be a gasoline or diesel powered engine), to help it burn more efficiently—and the end result should be improved gas mileage and reduced emissions.

But here's the misleading part of the many advertisements and claims we've read that kind-of ruffle our feathers, so-to-speak. An important, but glossed over point is that the engine isn't running on water, and it's not even running solely (or even predominantly) on this newly manufactured Brown's gas.

It simply mixes this gas (as a small percentage) with the vehicle's main fuel source. So, you still need to buy fuel--the main fuel tank still needs to be filled with petroleum--though perhaps not quite as often--and that continues to be the main fuel source.

And further, where does the electricity come from that breaks down the water into Brown’s gas?

It comes from your vehicle’s electrical system (battery and alternator). At the very least, the electrical system will have an additional load to power the hydrogen generator. Of course, this additional load is borne by the engine as it will actually have to work a little bit harder—and use more fuel—to drive the electricity-producing alternator.

Increased Fuel Economy?

Purveyors of these conversion kits claim a 15 to 20 percent increase in fuel economy. While that may be true, it probably varies tremendously from vehicle to vehicle and installation to installation. Something to keep in mind is that modern engines are designed to run efficiently and cleanly on the fuel that they were engineered to burn. Studies have shown that conversions often negatively affect emissions. According to the U.S. Department of Energy, “In the mid 1990s, testing determined that some vehicles converted to operate on alternative fuels, specifically natural gas and propane, produced worse emissions than those of baseline gasoline vehicles.”

Potential Pitfalls

One of the first places we’d expect to see problems develop would be oxygen sensor misreadings. Remember that Brown’s gas has a component of oxygen in addition to the hydrogen—that additional atom of oxygen could conceivably “fool” the O2 sensor into seeing a lean fuel condition.

In this scenario, the onboard computer would then direct the fuel system to increase fuel delivery to enrich the mixture, thereby potentially increasing fuel consumption and emissions. Modern engines require a very delicate balance of air and fuel, with their myriad electronic sensors and computer-controlled fuel, ignition and emission systems.

That said, if you really want to try one of these, we would suggest you use an older, second or third car or truck (mid-90s or older) as a guinea pig—not your primary vehicle. If the system works well for you, and provides results you’re happy with, you can then decide if you want to expand it to your other vehicle(s).

5 Points to Remember

Here are the things we recommend considering before purchasing a water conversion kit:

  • Cost of the kit: They can range from a cheapie ($200-300) to high quality ($2,000+), with well-made hardware that’ll perform better and last longer—of course, this affects your payback period also.
  • Assess your mechanical ability. Will you have to rely upon someone else for troubleshooting and occasional repair issues, or can you do these yourself?
  • Do you have an older second car that can be used as your test-bed? Try a kit on your spare mid-90s or older car. If it works out, great, if not, the loss is not so big.
  • Will you remember to monitor and maintain the system? The bare minimum would involve keeping the water tank full and associated regular maintenance.
  • Do you want to be able to get in, turn the key and go? We emphasize that you need to be a strong DIYer—with a curiosity and determination to do something different—and be willing/able to put the time into it.

So, is an HHO conversion worth it? We believe in a fleet environment, where there are many vehicles logging many miles---and there’s a dedicated service staff, this could be an effective way to save fuel. However, for the average individual (unless s/he is a handy DIYer), the potential pitfalls probably outweigh the benefits. When inevitable problems do arise, troubleshooting will fall to the individual or neighborhood mechanic, who may or may not have an understanding of how the system works.

Are we saying individuals should avoid water conversions? No. We're saying it may not work as simply, or as well, as the claims made by the manufacturers. Converting a dedicated system does compromise the integrity of the overall system. They usually don’t work as well—or efficiently—as they could (i.e. perhaps the alternator or drive belt may need frequent replacing). Plus, do these kits work through all the seasons? Does the hydrogen generator provide trouble-free service through winter’s cold snaps too?

Out of the above five points, we can’t stress enough that you need to honestly assess your own mechanical aptitude and DIY-ness. Beyond simply installing the kit, there will most certainly be maintenance, repair and trouble-shooting issues that you’ll have to deal with—and the answer certainly won’t be at your car dealer—and probably won’t be down at the corner garage either.

While it may be helpful to find an online community of folks, this is one trip on which you’ll likely find yourself sailing the voyage alone.