EurActiv - Letters to the Editor


Regarding ‘Test shows E10 increases fuel consumption‘:

The idea that ethanol has 40% less energy than gasoline that is given as the excuse for why it causes a mileage loss is not factual. Internal combustion engines only make a 15-25% efficient use of fossil fuel, meaning 75-85% of the energy potential of gasoline and diesel fuel is lost to the mechanics and ignition process the vehicle. The percentage can vary widely depending on many varying factors.

If the case for a lower energy content in ethanol is credible, why does 100% ethanol in a flex fuel engine result in the same or better mileage than gasoline, and why can the same be achieved using hydrous ethanol when hydrous ethanol has a lesser energy value than the kind of ethanol added to gasoline?

The kind of ethanol mixed with gasoline is anhydrous ethanol, meaning all the water has been distilled out of it so it can be mixed with gasoline. Hydrous ethanol still has the water in it and gets equal to better mileage than gasoline when clearly it has a lesser energy content. The issue is not energy content but how that energy is used.

Ethanol has an octane of 110. Governments that force it on the world’s fuel markets claim that when mixing it with lower octane fuels, they factor in the higher octane of ethanol to get the advertised octane, such as by lowering the octane of the gasoline it’s added to so it balances it out to provide the octane you are told you are buying, or they say that when using ethanol at 5 or 10%, the increase in octane is so marginal that it is not a problem. They even claim it enhances octane and is needed for better combustion since lead is no longer added to gasoline.

The problem with these arguments is that ethanol does not actually blend with gasoline into one fuel. This is evidenced by the fact that if ethanol in gasoline comes in contact with water, it will attach to the water and settle to the bottom of the fuel tank. In Netherlands, they actually blend hydrous ethanol with gasoline at the refinery so it actually becomes one uniform fuel. This eliminates the water separation and mileage problem altogether. The way it’s done almost everywhere else is to simply mix ethanol and gasoline without a chemical process to bind them together as one fuel. The problem with this is that it results in there being two octanes in one fuel.

Octane is the burn rate of gasoline. It has to do with the timing and compression ratio. Ignition system sensors and computers analyse the burn rate of whatever fuel is being used and adjust the timing and compression ratio to make the best use of it. This is supposed to result in better performance and mileage.

But when ethanol is added to gasoline, this highly efficient process become useless, since there’s no way to adjust for two different fuels with two different octanes being used at the same time. In many cases, the amount of loss of power due to this factor is greater than the amount of ethanol added to gasoline, such as losing 10 to 15% mileage with there is 10% ethanol in the gasoline.

This is especially true here in the US, where most cars are designed to run on 87 octane with such a wide gap between ethanol’s 110 octane and the gasoline it is added to. This means that overall, we are importing more fossil fuels to make up for the loss of mileage caused by adding ethanol, not to mention the burden it puts on the economy and energy markets to produce this pretend fuel product.

The reason the US uses ethanol has nothing to do with it being a fuel and everything to do with politics. In fact it’s not even referred to as a fuel behind closed doors in Washington but as an oxygenate. It replaced another oxygenate named MTBE in 2006. Oxygenates have to do with air quality, not mileage or octane. Their history is long and sordid with most of what governments say about them being untrue. Oxygenates are purposely designed to cause a loss of mileage to increase emissions of volatile organic compounds (VO’s) like formaldehyde and acetaldehyde. VOCs mix with nitrogen oxides (Nox) in the sun to form low level ozone.

At the time oxygenates were first required by the US EPA, NOx smog from coal burning and diesel engines darkened the skies over US cities. This prompted many complaints by citizens worried about their health. So oxygenates were required in gasoline to create high levels of VOCs to dissolve the smog. MTBE was chosen over ethanol because it was cheaper to produce and could be transported through pipelines.

When it turned out that MTBE was polluting groundwater everywhere it was used, ethanol was assigned to replace it. Then California took the EPA to court and proved that oxygenates actually worsen air quality over the smog it gets rid of, because the formaldehyde, acetaldehyde, and ozone byproducts of its use are more dangerous than the unsightly smog it dissolves.

Then President Bush stepped in and said it was no longer being required as an oxygenate but as a fuel to lesson the United States’ dependence on foreign oil citing ethanol use as matter of national security. He referred to Brazil’s successful efforts to with ethanol to eliminate its imports of almost all fossil fuel products.

The thing is that Brazil primarily uses E100 hydrous ethanol used with ignition systems designed to burn it without a mileage or pollution problem. Since much of the world followed the United States lead on MTBE use, they also followed us on adding ethanol to gasoline.

The politics of how this happened and why it hasn’t changed is complex and a testament to how corrupt the political system here in the US is. If Germany is persistent in choosing to follow the US model for ethanol over the way it’s used in Netherlands and Brazil, or the even better ways we could be producing biofuels that are being ignored in Washington, your strong economy will head the same direction ours did after our E10 programme first began, down the toilet.

Bobby Fontaine

Private citizen

Author :


Comments are closed.