Butanol: A Superior Renewable Energy Substitute for Gasoline

Oil prices hover close to US $70 a barrel. This higher price drives a lot of research into finding substitutes for petroleum fuels. Ethanol is the cause celebre of the news media, but two-carbon ethanol is not nearly as good a gasoline substitute as is butanol, a four-carbon alcohol. Here is more information from Butanol.com:

* Higher energy content (110,000 Btu’s per gallon for butanol vs. 84,000 Btu per gallon for ethanol). Gasoline contains about 115,000 Btu’s per gallon.
* Butanol is six times less “evaporative” than ethanol and 13.5 times less evaporative than gasoline, making it safer to use as an oxygenate in Arizona, California and other states, thereby eliminating the need for very special blends during the summer and winter months.
* Butanol can be shipped through existing fuel pipelines where ethanol must be transported via rail, barge or truck
* Butanol can be used as a replacement for gasoline gallon for gallon e.g. 100%, or any other percentage. Ethanol can only be used as an additive to gasoline up to about 85% and then only after significant modifications to the engine. Worldwide 10% ethanol blends predominate.

Here is a list of the advantages of butanol from Pure Energy Systems:

# Higher energy content than ethanol.
# Not as corrosive as ethanol.
# Uses an air/fuel ratio which is close to that of gasoline. Ethanol does not.
# Can be shipped through existing fuel pipelines where ethanol must be transported via rail, barge or truck.
# Can replace gasoline any percentage up to 100%. Ethanol can only be used up to 85%.
# Gives better mileage than ethanol. (http://www.businessweek.com/autos/content/apr2006/bw20060427_493909.htm?chan=autos_autos%20indexpage_insight)
# Safer to handle than ethanol.
# Will also assist in the conversion of vegetable oils into biodiesel.

Here is a list of butanol advantages from lightparty:

Butanol is a four carbon alcohol. It has double the amount of carbon of ethanol, which equates to a 25 percent increase in harvestable energy (Btu's).

Butanol is produced by fermentation, from corn, grass, leaves, agricultural waste and other biomass.

Butanol is safer to handle with a Reid Value of 0.33 psi, which is a measure of a fluid's rate of evaporation when compared to gasoline at 4.5 and ethanol at 2.0 psi.

Butanol is an alcohol that can be but does not have to be blended with fossil fuels.

Butanol when consumed in an internal combustion engine yields no SOX, NOX or carbon monoxide all environmentally harmful byproducts of combustion. CO2 is the combustion byproduct of butanol, and is considered environmentally 'green'.

Butanol is far less corrosive than ethanol and can be shipped and distributed through existing pipelines and filling stations.

Butanol solves the safety problems associated with the infrastructure of the hydrogen supply. Reformed butanol has four more hydrogen atoms than ethanol, resulting in a higher energy output and is used as a fuel cell fuel.

Butanol is an industrial commodity, with a 370 million gallons per year market with a selling price of $3.75 per gallon.

Hydrogen generated during the butanol fermentation process is easily recovered, increasing the energy yield of a bushel of corn by an additional 18 percent over the energy yield of ethanol produced from the same quantity of corn.

Here are even more advantages for butanol from Environmental Energy Inc.:

Environmental Energy Inc has shown that BUTANOL REPLACES GASOLINE - 100 pct and has no pollution problems, and further proved it is possible to produce 2.5 gallons of butanol per bushel corn at a production cost of less than $1.00 per gallon. There are 25 pct more Btu-s available and an additional 17 pct more from hydrogen given off, from the same corn when making butanol instead of ethanol that is 42 pct more Btu-s more energy out than it takes to make - that is the plow to tire equation is positive for butanol. Butanol is far safer to handle than gasoline or ethanol. Butanol when substituted for gasoline gives better gas mileage and does not pollute as attested to in 10 states. Butanol should now receive the same recognition as a fuel alcohol in U.S. legislation as ethanol.

Besides using butanol as a straight substitute for gasoline, butanol can be blended with diesel or biodiesel and burned in diesel engines. When you combine the processes of producing biodiesel from oil seeds, and butanol from biomass, you can fuel all the vehicles on the highway. Then if you use byproducts of those processes in fuel cells to produce electricity, your overall efficiency goes even higher.

Here is a good article on butanol from Green Car Congress, a more recent article from R-Squared, and also a fine article from Fat Knowledge blog. Be sure to read the comments.

Ramping up butanol infrastructure is a matter of investment and chemical/manufacturing engineering technology. The public relations battle against the ethanol super-giants is another matter. Ethanol is represented by big farm conglomerate money, among other big business interests, and has its hands in government pockets. Government officials listen to ethanol. Butanol is the David against the ethanol Goliath. But Butanol is clearly the better man, so Butanol will eventually win. We should all hope that smaller farm interests will wake up to the possibilities, pool their resources, and put butanol on the main track soon.