NASA Reports

NASA Reports Hydrogen and Gasoline Mix Increases Mileage
Posted on August 28th, 2008 by admin

U. S. space agency NASA has been using hydrogen fuel cells since the 1960s to provide power for astronauts aboard their spacecraft. The hydrogen fuel cells have also provided drinking water for the space goers. UTC Power hydrogen fuel cells have been aboard all Space Shuttle flights with over 100,000 operating hours to their credit.

But, what many people don’t know is that back in May 1977, NASA also came out with a document stating that hydrogen helps gasoline-powered internal combustion engines increase mileage and lower emissions.

A week ago, I talked about how the U. S. Department of Transportation (DOT) made the same claim just last year. Some critics have stated that if hydrogen injection is such a viable technology, then why isn’t our government talking about it. The short answer is, they are. We just haven’t known where to look to find the details.

According to the 31 year old document titled, “Emissions and Total Energy Consumption of a Multicylinder Piston Engine Running on Gasoline and a Hydrogen-Gasoline Mixture” adding small amounts of hydrogen to the gasoline and air mix extends the lean range of the vehicle.

In other words, hydrogen with its higher flame speed help lean out or use less gas thereby increasing mileage and reducing the tailpipe emissions. According to NASA, “Using a small quantity, on a weight basis, of hydrogen as a supplement to gasoline was chosen as a way to extend lean engine operation. Onboard generation of hydrogen was selected as a feasible way to use hydrogen in a mobile application.”

Both NASA and the U. S. DOT have validated that using hydrogen in a gasoline-powered vehicle will increase mileage and reduce emissions. Many thanks to Wilson over at run your car on water for the heads up on this hydrogen injection document that has been sitting around unnoticed for many years now. As the critics of hydrogen fuel injection fall by the wayside, many small entrepreneurs will be newly energized with building more efficient hydrogen generators that give us all an avenue for greener cars now.

NASA in their Technical Note Report E-9105 (NASA-TN-D-8487) published May 1, 1977:
• This report is titled “Emissions And Total Energy Consumption Of A Multicylinder Piston Engine Running On Gasoline And A Hydrogen-Gasoline Mixture”, and NASA’s abstract (in their archives today) says: “A multicylinder reciprocating engine was used to extend the efficient lean operating range of gasoline by adding hydrogen. Both bottled hydrogen and hydrogen produced by a research methanol steam reformer were used. These results were compared with results for all gasoline. A high-compression-ratio, displacement production engine was used. Apparent flame speed was used to describe the differences in emissions and performance. Therefore, engine emissions and performance, including apparent flame speed and energy lost to the cooling system and the exhaust gas, were measured over a range of equivalence ratios for each fuel. All emission levels decreased at the leaner conditions. Adding hydrogen significantly increased flame speed over all equivalence ratios.”
• This research focused on using hydrogen as a supplemental fuel to gasoline to a 1969 production engine. The research demonstrated that the higher flame speed of hydrogen was responsible for being able to extend the efficient lean operating range of a gasoline engine:
• “Lean-mixture-ratio combustion in internal-combustion engines has the potential of producing low emissions and higher thermal efficiency for several reasons. First, excess oxygen in the charge further oxidizes unburned hydrocarbons and carbon monoxide. Second, excess oxygen lowers the peak combustion temperatures, which inhibits the formation of oxides of nitrogen. Third, the lower combustion temperatures increase the mixture specific heat ratio by decreasing the net dissociation losses. Fourth, as the specific heat ratio increases, the cycle thermal efficiency also increases, which gives the potential for better fuel economy.”
• “Adding hydrogen to gasoline significantly increased flame speed and allows for a leaner air-fuel ratio. All emissions levels decreased at these leaner conditions….significantly increased flame speed and allows for a leaner air/fuel ratio. All emissions levels decreased at these leaner conditions.”
• “The results were used to explain the advantages of adding hydrogen to gasoline as a method of extending the lean operating range. The minimum-energy-consumption equivalence ratio was extended to leaner conditions by adding hydrogen, although the minimum energy consumption did not change. All emission levels decreased at the leaner conditions. Also, adding hydrogen significantly increased flame speed over all equivalence ratios.”
• The official document may be downloaded from NASA Archives (document ID 19770016170):
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19770016170_1977016170.pdf