Alternative Fuels Georgia Agriculture Education May 2007 Why Alternative Fuels? • As the cost of conventional fuels goes up, the interest in other fuel sources increase • In some cases, alternative fuels are more environmentally friendly • Some alternative fuels are more energy efficient Types of Alternative Fuels • Ethanol • Natural gas • Propane • Hydrogen • Biodiesel • Electricity • Methanol Ethanol • Ethanol is an alcohol-based alternative fuel produced by fermenting and distilling starch crops or cellulose that have been converted into simple sugars • Ethanol is most commonly used to increase octane and improve the emissions quality of gasoline. • Ethanol can be blended with gasoline to create E85, a blend of 85% ethanol and 15% gasoline. • Ethanol can degrade quickly in water, therefore, posing less environmental harm than oil in the case of a spill Ethanol • Ethanol is an excellent, clean-burning fuel, potentially providing more horsepower than gasoline. In fact, ethanol has a higher octane rating (over 100) and burns cooler than gasoline • One acre of corn can produce 300 gal. of ethanol per growing season. So, in order to replace that 200 billion gal. of petroleum products, American farmers would need to dedicate 675 million acres, or 71 percent of the nation's 938 million acres of farmland, to growing feedstock. Natural Gas • Natural gas is produced either from gas wells • or in conjunction with crude oil production. • Because of the gaseous nature of this fuel, it must be stored onboard a vehicle in either a compressed gaseous state or in a liquefied state • A natural gas vehicle can be less expensive to operate than a comparable conventionally fueled vehicle depending on natural gas prices. • The United States has vast natural gas reserves across the country • Vehicles tend to cost $3500 to $6000 more than gasoline powered ones Propane • Propane or liquefied petroleum gas (LPG) is a popular alternative fuel choice for vehicles because there is already an infrastructure of pipelines, processing facilities, and storage for its efficient distribution. • LPG produces fewer vehicle emissions than gasoline. • Propane is produced as a by-product of natural gas processing and crude oil refining. • Propane vehicles can produce fewer ozone-forming emissions than vehicles powered by reformulated gasoline • The cost of a gasoline-gallon equivalent of propane is generally less than that of gasoline, so driving a propane vehicle can save money. Hydrogen • Hydrogen, a gas, will play an important role in developing sustainable transportation in the United States, because in the future it may be produced in virtually unlimited quantities using renewable resources. • Hydrogen and oxygen from air fed into a proton exchange membrane fuel cell produce enough electricity to power an electric automobile, without producing harmful emissions. The only byproduct of a hydrogen fuel cell is water. • Currently there are no original equipment manufacturer vehicles available for sale to the general public. Experts estimate that in approximately 10-20 years hydrogen vehicles, and the infrastructure to support them, will start to make an impact. Biodiesel • Biodiesel is a domestically produced, renewable fuel that can be manufactured from vegetable oils, animal fats, or recycled restaurant greases. • Biodiesel is safe, biodegradable, and reduces serious air pollutants such as particulates, carbon monoxide, hydrocarbons, and air toxics. • Biodiesel can also be used in its pure form but it may require certain engine modifications to avoid maintenance and performance problems and may not be suitable for wintertime use. Biodiesel • Pure biodiesel, B100, costs about $3.50-- roughly a dollar more per gallon than petrodiesel. • Need to heat storage tanks in colder climates to prevent the fuel from gelling • Like E85, biodiesel began with farm co-ops and local entrepreneurs. High fuel prices affect farmers, too, and here was an opportunity to make money from otherwise fallow farmland. Electricity • Electricity can be used as a transportation fuel to power battery electric and fuel cell vehicles. When used to power electric vehicles, electricity is stored in an energy storage device such as a battery. • EV batteries have a limited storage capacity and their electricity must be replenished by plugging the vehicle into an electrical source. • EVs have lower "fuel" and maintenance costs than gasoline-powered vehicles. Electricity • Vehicles that operate only on electricity require no warm-up, run almost silently and have excellent performance up to the limit of their range. Also, electric cars are cheap to "refuel." At the average price of 10 cents per kwh, it costs around 2 cents per mile. • Pure electric cars still have limited range, typically no more than 100 to 120 miles. Methanol • Methanol, also known as wood alcohol, can be used as an alternative fuel in flexible fuel vehicles that run on M85 • It is not a commonly used fuel at this time as methanol produces a high amount of formaldehyde in emissions. • The benefits include lower emissions, higher performance, and lower risk of flammability than gasoline • Methanol can easily be made into hydrogen for hydrogen fuel cell vehicles in the future. Methanol • Methanol is extremely corrosive, requiring special materials for delivery and storage. Methanol, in addition, has only 51 percent of the BTU content of gasoline by volume, which means its fuel economy is worse than ethanol's. • Methane also can be produced by processing biomass such as grass clippings, sawdust and other cellulose sources.
Pages to are hidden for
"Alternative Fuels"Please download to view full document