Emerging Fuels Contribute to Diverse Energy Portfolio - Environmental Auto Services

While alternative fuels like ethanol and propane tend to steal the spotlight, there remains a number of emerging or newly develop alternative fuels that could have some impact on the nation's future energy portfolio. Most experts agree that the U.S. needs to diversify its transportation fuel dependency and some of these emerging fuels may help to meet that objective.

Though some are still under development, a number of these new energy sources are considered alternative fuels by definition under the Eengy Policy Act of 1992, in which case they could qualify for federal and state incentives regarding their use. There are also other fuels which could meet the requirements of an alternative fuel, under certain conditions.

Biobutanol
Biobutanol may not be as common as ethanol, but it has many of the same qualities. Chemically, butanol is defined as a 4-carbon alchol known as butyl alcohol. When butanol is poduced from biomass feedstocks, it becomes the renewable form, biobutanl. Butanol itself is most commonly found in industrial applications, such as solvents and enamels.

However, biobutanol is more commonly seen as an alternative fuel for vehicles. A butyl-fuel vehicle powered 100% by biobutanol was driven across the entire country. Just like ethanol, biobutanol is a liquid alcohol fuel and can be used in existing gasoline-powered internal combustion enines. It is also easily blended with gasoline as well as added to the ethanol blending process with gasoline. Energy content for biobutanol is about 10 to 20 percent lower than that of gasoline, so the price has to be right for wider adaptation.

The EPA allows for biobutanol to beblended as an oxygenate with gasoline, in concentrations up to 11.5 percent by volume. However, blends of 85% or more of biobutanol with gasoline are necessary to qualify as an EPAct alternative fuel. Although it has not been officially tested, biobutanol's propents claim the alternative fuel could replace gasoline up to 100% with little to no vehicle modification and not cause problems.

Biogas
Waste not, want not. That could be the theme of biogas. This gaseous product comes about due to the anaerobic digestion, or decomposition without oxygen, of various types of organic matter. Generally, it is made up of about 50 to 80% methane, about 20 to 50% carbon dioxide and generally some traces of other gases, such as nitrogen, carbon monoxide or hydrogen. It differs from natural gas, which is typically made up of about 70% methane and the remainder other hydrocarbons with only small amounts of carbon dioxide. Biogas has worn many labels through the years, from landfill gas to digester gas to swamp gas. It is sometimes called renewable natural gas, once its compositon has been upgraded to a higher standard of purity.

When biogas has been purified to the required level, then either compresed or liquefied, it can serve as an alternative vehicle fuel. It can take o nthe same forms as more conventionally derived natural gas, namely compressed natural gas or liquefied natural gas.

Worldwide, biogas is making headway. In fact, a 2007 report estimated that 12,000 vehicles are being fueled with upgraded biogas around the globe, with 70,000 biogas-fueled vehicles predicted by the next year or two. Europe leads with the most of these vehicles, though half of the gas used in Sweden's 11,500 natural gas vehicles is biogas.
Biogas has not taken off as much in the U.S. though there are a few examples, particularly in California, of landfills that produce LNG from biogas.