Undercar: Diagnosing And Repairing Wheel Bearing Noise
Vehicle manufacturers are searching for the ultimate Alternative-Fuel Vehicle
By Kathleen Quinn Larson
President, Alternative Energy Education Associates
Everyone with a driver’s license has experienced the increasing “pain at the pump” of soaring gasoline prices. With more than 250 million cars on the road, the growing dependence on foreign oil is a topic on almost every nightly news program.
The effect of carbon emissions on Global Warming is also at issue and automobile exhaust is one of the largest contributors. The development of alternative fuel options for transportation is an issue that almost everyone agrees upon, even the National Petroleum Council, a consortium of U.S. oil companies, expressed the need for increased efforts to develop alternative fuels in their report, “Facing the Hard Truths about Energy.”
In 2007 the U.S. domestic production of crude oil was approximately 5,000,000 barrels a day. Imports from foreign countries were more than 10,000,000 a day. Experts say that the development of drilling in the Alaska wilderness will increase production by only about 1 million barrels a day, and that production will not reach the gas pumps until the year 2013.
And, the U.S. government estimates that opening the Atlantic and Pacific coasts and eastern Gulf of Mexico to drilling “will not have a significant impact on domestic crude oil and natural gas production or prices before 2030.” Even then, it would only increase domestic oil production by 3%.
While this may help some, the fastest and most efficient way to reduce our dependence on foreign oil, to bring down the high cost of transportation, and to reduce carbon emissions produced by transportation is to improve fuel efficiency in the cars we drive and to develop alternative fuel vehicles. The U.S. Congress passed a bill that requires auto manufactures to improve fuel efficiency from the current 24 mpg to 35 mpg by the year 2020.
The highest-rated gasoline car on the road today is the Toyota Yaris which has a fuel efficiency of 29 mpg city and 36 mpg highway. Improving fuel efficiency will decrease both the amount of fuel used and the greenhouse gas emissions, but it will not be enough. The automobile of the future that will completely eliminate carbon emissions and bring complete energy independence for transportation fuel is the hydrogen fuel cell vehicle.
Most of the major auto manufacturers are developing alternative fuel vehicles including electric, electric hybrid, electric plug-in, CNG (Compressed Natural Gas), biodiesel, ethanol and hydrogen fuel cells. Gasoline-electric hybrids, such as the Toyota Prius and the Ford Escape Hybrid, have made their way into the mainstream automotive market.
The Prius offers an average fuel rating of 48 mpg for city driving. Regenerative breaking which charges the batteries helps increase the fuel efficiency of electric hybrid automobiles, but they still rely on gasoline.
General Motors expects to begin mass production of the Volt, a plug-in electric vehicle, in 2010. The only greenhouse emission from the use of electric cars comes from the production of electricity at the power plant which provides electricity to homes.
While the Volt and other electric cars will have no emission directly from the automobile, since the majority of residential electricity in the U.S. comes from coal power, the electricity used to power electric cars has a large carbon footprint. The most significant disadvantage of the electric car is that it will have a range of only about 40 miles.
Improvements being made to the lithium-ion batteries used in the Volt may help to increase this range slightly. While quick charging technology is improving, the amount of time it takes to recharge the vehicle is also still a disadvantage.
We have seen CNG vehicles, especially busses, on our road for many years. The Honda Civic GX, a natural gas automobile, has been called “the cleanest internal-combustion vehicle on Earth.
The advantage of CNG is that it is about 90% cleaner than gasoline, but it does still contain some carbon emissions. Another advantage of CNG is that 85% of the CNG used in the U.S. is produced in the U.S. As a matter of fact, Honda offers a home refueling system, Phill, for consumers who already have a natural gas line to their homes.
However, natural gas is a limited resource; the amount of natural gas available to produce is finite. Honda has released the Civic GX in a few limited locations where natural gas refueling stations are available to the public. The performance of CNG cars does not differ significantly from a gasoline car. One of the biggest disadvantages of the performance CNG vehicles is that they are difficult to start in extreme cold.
Bio-diesel and ethanol fuel are becoming a prominent alternative fuel source worldwide. Combustion of biodiesel provides a 56% reduction in the hydrocarbon emissions compared to petroleum-based diesel fuel, and ethanol can reduce emissions by 12% to 50% depending on the source used to create the ethanol. While biodiesel can be easily produced from waste oil used in food preparation, studies show that it can reduce vehicle fuel economy and is difficult to operate in cold temperatures.
Biodiesel and ethanol are an important alternative to petroleum products in the short term. However, both bio-diesel and ethanol are produced from agricultural crops and if land is used to produce energy for transportation, the world food production and cost could be seriously impacted.
Hydrogen Fuel Cell
Hydrogen fuel cell vehicles can offer a completely clean alternative fuel for transportation that will allow for energy independence and no greenhouse emissions. All major auto manufacturers have developed fuel cell automobile prototypes and expect to begin offering vehicles to the public within the next 10 years.
Honda has begun leasing the Clarity fuel cell vehicle to consumers in a small region of Southern California that has hydrogen refueling stations available. General Motors expects to have a fleet of 10,000 fuel cell cars by the year 2015 and 100,000 in 2018.
Fuel cell busses are in operation in a number of cities around the world, and companies such as UPS are testing small fleets of fuel cell vehicles in their operations.
Fuel cell cars are electric vehicles which use an electro-chemical reaction to produce the electricity onboard and the only by-products are heat and water. When Rick Wagoner, the CEO of General Motors demonstrates his company’s fuel cell cars, he often drinks the water dripping from the tailpipe to show how clean the emissions are. Fuel cell cars will have about 1/10 the number of parts in a combustion engine vehicle making them much easier to manufacture and repair.
Fuel cell cars have a range of about 250 miles, making them more appealing than electric vehicles with limited range. One drawback of fuel cell vehicles is the limited life of the membrane which does the work of producing electricity. Scientists are hurrying to produce fuel cells that will have a longer life.
Many people are concerned about the safety of hydrogen gas in automobiles. Actually, hydrogen gas in automobiles is safer than gasoline. Hydrogen is the lightest element on earth, so when a hydrogen tank is compromised, the gas immediately rises and disperses.
If a spark causes a fire, the flames up and away from the vehicle rather than surrounding the vehicle like a gasoline fire does.
The biggest barrier to fuel cell vehicles is the availability of a hydrogen infrastructure. Today, more than 85% of all hydrogen is produced by steam-reforming natural gas. There is a loss of energy in the transfer, so using natural gas to produce hydrogen is not efficient and natural gas is a limited resource.
Hydrogen can be produced from a variety of sources including biodiesel, ethanol and by using renewable energy such as solar, wind, and geothermal power to split water into hydrogen and oxygen. Solar and wind power are not convenient sources of electricity for automobiles. Using the excess power from solar or wind power to produce hydrogen transfers that energy into one which is portable.
As solar and wind power technology is advanced and the availability of renewable energy to produce hydrogen becomes more abundant, hydrogen fuel cell cars will become the best alternative to petroleum based transportation fuel in the long term. How long is the long-term?
Some experts expect to see fuel cell cars as a mainstream vehicle as soon as 15 years from now, others estimate 40 years, but major automotive manufacturers are spending millions of dollars now expecting to sell hydrogen fuel cell cars to the public in the future.
Kathleen Quinn Larson is the president of Alternative Energy Education Associates, a company devoted to bringing renewable energy products and education to the public. Larson is a frequent presenter for the North American Council of Automotive Instructors and has been an invited speaker for the National Hydrogen Association, Fuel Cell Seminar and Exposition and the National Science Teachers Association.