Advanced Technology and Alternative Fuel Vehicles. Energy
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DOE/GO-102001-1142 FS143 August 2001 Advanced Technology and Alternative Fuel Vehicles Surveys show that Americans are con- 67 percent of the oil we consume in the cerned about the environment, global United States—more than we produce. warming, and related issues. Yet many Today, our country imports more than don’t realize that the cars and trucks they 54 percent of its oil supply, and it's drive are a major source of these prob- estimated that this could increase to lems, and that there are alternative 75 percent by 2010. choices they can make today. According to the U.S. Federal Highway Most of us drive or ride in vehicles that Administration, the average vehicle (car are powered by petroleum-based fossil or light truck) on the road today emits fuels — gasoline or diesel. Some people, more than 600 pounds of air pollution however, are choosing to drive vehicles each year. These pollutants (such as car- that run on smaller amounts of fuel, bon monoxide, sulfur dioxide, nitrogen and/or partially or completely on fuels dioxide, and particulate matter) contribute other than diesel or gasoline. These to smog and to many health problems. For advanced and alternative fuel vehicles example, smog can cause eye and respira- (AFVs) help reduce our dependence on tory tract irritation, and carbon monoxide foreign oil imports, save us money on fuel can inhibit the ability of a person's blood costs, and improve our air quality. to carry oxygen to vital organs. Why Drive an Advanced or The average vehicle, through its combus- Alternative Fuel Vehicle? tion of fossil fuels, also emits greenhouse Transportation accounts for more than gases. Greenhouse gases—such as carbon Warren Gretz, NREL/PIX07070 Gretz, Warren Advanced and alternative fuel vehicles help reduce emissions that cause air pollution, smog, and global warming. This document was produced for the U.S. Department of Energy (DOE) by the National Renewable Energy Laboratory (NREL), a DOE national laboratory. The document was produced by the Information and Outreach Program at NREL for the DOE Office of Energy Efficiency and Renewable Energy. The Energy Efficiency and Renewable Energy Clearinghouse (EREC) is operated by NCI Information Systems, Inc., for NREL / DOE. The statements contained herein are based on information known to EREC and NREL at the time of printing. No recommendation or endorsement of any product or service is implied if mentioned by EREC. Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% postconsumer waste Today’s Alternative Fuel Choices Alternative fuels not only burn cleaner— producing lower emissions—but some are even renewable, unlike fossil fuels, which means we could develop a continu- ous supply of them. The alternative fuels in use today include ethanol, biodiesel, methanol, natural gas, propane, electricity, and hydrogen. Biofuels Biofuels are renewable since they are produced from biomass—organic matter, such as plants. They generate about the same amount of carbon dioxide (a greenhouse gas) from the tailpipe as fossil fuels, but the plants that are grown to produce the biofuels actually remove Warren Gretz, NREL/PIX00246 Gretz, Warren carbon dioxide from the atmosphere. This snowplow in Minnesota runs on ethanol. Therefore, the net emission of carbon dioxide will be close to zero. dioxide, methane, nitrous oxide, hydrocar- bons, and chlorofluorocarbons—surround Ethanol the Earth's atmosphere like a clear thermal blanket, allowing the sun's warming rays The most widely used alternative trans- in and trapping the heat close to the portation fuel is ethanol. Ethanol is an Earth's surface. This natural greenhouse alcohol typically made from corn or corn effect keeps the average surface tempera- byproducts, using a process similar to ture at around 60˚F (33˚C). brewing beer. Vehicles that run on ethanol have lower carbon monoxide and carbon However, the increased use of fossil fuels dioxide emissions than traditional vehi- during the last century has created an cles. enhanced greenhouse effect, known as In the United States, we blend more than global warming. And transportation has 1.5 billion gallons of ethanol with gasoline played a large role in this increase. each year to produce E10 (10 percent ethanol and 90 percent gasoline.) E10 can During the 1990s, the annual growth rate be used in most of the vehicles we’re of U.S. greenhouse gas emissions from driving on the roads today. As a result, transportation averaged 1.6 percent. In we’re already using E10 across the country 1999, some 82 percent of U.S. greenhouse to improve vehicle performance and gas emissions consisted of carbon dioxide reduce air pollution. Alternative fuels released by the combustion of energy fuels. The U.S. Environmental Protection Today we also have some vehicles that not only burn cleaner, Agency (EPA) estimates that each year the can use a higher blend of ethanol – up to average light vehicle in the United States 85 percent – called E85. These vehicles, but some are even releases 10,000 pounds of carbon dioxide known as flexible-fuel vehicles, can use into the air. Motor gasoline contributed E85, gasoline, or any mixture of the two. renewable. close to 300 million metric tons of carbon E85 is available in many parts of the coun- dioxide, making it the largest single try but primarily in the Midwest. source of U.S. carbon dioxide emissions. By reducing vehicle emissions, AFVs and advanced vehicle technologies help combat both air pollution and global climate change. 2 Biodiesel Biodiesel is an ester (similar to vinegar) that can be made from several types of oils, such as vegetable oils and animal fats. There are about Each year about 30 million gallons of biodiesel are produced in the United 100,000 natural gas States from recycled cooking oils and soybean oil. vehicles in the Biodiesel is currently not available to the United States. general public. Some federal, state, and transit fleets, as well as tourist boats and launches, use biodiesel either alone or blended with another fuel. Biodiesel is typically used as a blend— 20 percent biodiesel and 80 percent petroleum diesel—called B20. B20 can be used in a conventional diesel engine with essentially no engine modifications. There is also a growing interest in using NREL/PIX03830 Gretz, Warren biodiesel where workers are exposed to There are approximately 600 public, CNG diesel exhaust, in aircraft to control local refueling stations across the country. pollution near airports, and in locomotives that face restricted use unless vehicles. Some buses and fleet vehicles emissions can be reduced. currently run on M85, which contains 85 percent methanol and 15 percent gasoline. Methanol Natural Gas Methanol, another alcohol-based fuel, is usually produced from natural gas, but Natural gas is a mixture of hydrocarbons, it can also be produced from biomass. mainly methane. It can be produced either Therefore, it has the potential to help from gas wells or in conjunction with reduce petroleum imports. crude oil production. Natural gas is a clean burning, domestically Methanol-powered vehicles emit smaller produced fuel that generates significantly amounts of air pollutants, such as hydro- less carbon monoxide, carbon dioxide, carbons, particulate matter, and nitrogen particulate matter, and nitrous oxide oxides, than do similar gasoline-fueled compared to similar fossil fuel vehicles. It is used in vehicles as compressed natural gas (CNG) or liquefied natural gas (LNG). There are about 100,000 natural gas vehicles in the United States. Nearly one of every five new transit buses in the United States runs on natural gas. Propane Liquefied petroleum gas (LPG), com- monly called propane, is a mixture of at least 90 percent propane, 2.5 percent butane and higher hydrocarbons, and ethane and propylene make up the remaining balance. It is a byproduct of natural gas processing and/or petroleum refining. Nebraska Soybean Board/PIX04231 Soybean oil can be used to make biodiesel, which powers this bus. 3 In 2000, close to 7,600 on-road EVs in the United States consumed electricity at an amount equivalent to about 1.7 million gallons of gasoline. Hydrogen Hydrogen is a simple, abundant element found in organic matter, notably in the hydrocarbons that make up many of our fuels, such as gasoline, natural gas, methanol, and propane. As an energy car- rier like electricity (not an energy source), it must be manufactured. Hydrogen can be made by using heat to separate it from the hydrocarbons. Currently, most hydro- gen is made this way from natural gas. Hydrogen can be combined with gasoline, ethanol, methanol, or natural gas to reduce nitrogen oxide emissions. Because the only byproduct of hydrogen is water, only the engine lubricants from a hydro- gen-fueled vehicle emit small amounts of Warren Gretz, NREL/PIX06167 Gretz, Warren air pollutants. The sun’s energy, via a photovoltaic module, is used to recharge this electric vehicle. Hydrogen is already the fuel of choice for propelling space shuttles. It is also being A propane-powered vehicle can't run as explored for use in internal combustion far on a tank of gas as a comparable gaso- engines. Although hydrogen can be line-powered vehicle, but propane gener- burned in an internal combustion engine, ates lower vehicle emissions. Propane Propane is a or serve as a fuel additive, there's more emits 64 percent less reactive organic interest in using hydrogen to supply fuel compounds, 20 percent less nitrogen publicly accessible cells that power EVs (see “Fuel Cell Vehi- oxide, and 20 percent less carbon monox- cle” on page 6). ide than a similar gasoline vehicle. alternative fuel. P-Series Propane is a publicly accessible alternative P-Series is a relatively new alternative fuel.