Does added hydrogen really boost fuel mileage?

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Q: Do hydrogen-adding technologies really work to boost fuel mileage?

A: Some research shows that hydrogen slightly improves diesel combustion, but the improvement may not be significant enough to warrant all the equipment necessary to separate it and meter it back in. Hydrogen does not add any energy. It only helps the fuel burn a bit faster and more completely, and then only slightly.

Most people probably don’t realize that diesel fuel is two-thirds hydrogen anyway. So the probability that such a system will help the engine to run all that differently is likely to be small.

Water consists of hydrogen and oxygen bonded together. The systems I have seen use the electricity from the alternator to separate hydrogen from distilled water that the company supplies. The oxygen that was associated with the hydrogen in the water escapes and the hydrogen is then metered into the intake system. Using power from the alternator to make hydrogen will increase the load on the engine slightly.

Ideally, the maker of such a system will have had an SAE Type II test to verify any mileage increase. Anyone considering using the system should review the results. Then consider the cost of the system, including installation, and any recurring costs, like distilled water and maintenance. You should also find out what the current power draw for the system is and evaluate whether or not you’d need to install a more powerful alternator to handle it without strain.

You might want to check with your engine manufacturer to make sure doing this won’t void your warranty, though chances are the process would not have much effect on engine wear or stress.

Read Todd Dills’ Channel 19 blog about a hydrogen injection system in the testing phase.

Read a sales brochure for the Wildcat Hydrogen Booster, which is available for vehicles ranging from cars to heavy-duty trucks.

Got a maintenance or technological question for Overdrive Equipment Editor John Baxter? Post it in the comments here or email to [email protected]. Keep tuned to Overdrive Extra for the response.