There are different kinds of alternative fuels in the world at present. There are eight different types of alternative fuels which are Ethanol, Natural Gas, Propane, Hydrogen, Bio-Diesel, Electricity, Methanol
and P-series. All these alternative fuels have different properties, different source used, and different vehicle’s used and different impact on the environment and on the world. But one point to be noted is that even though they have different impact on environment, alternative fuels in vehicles can generally reduce harmful pollutants and exhaust emissions.
Another interesting fact I found about these fuels in particular is that they can rather be domestically produced and can be derived from renewable resource but the fossil fuels which are being used today such as petroleum and diesel cannot be derived from renewable source. Once these fossil fuels will be extinct alternative fuels are the one which will come to use.
I personally think that if even a small majority of the people in the world start using alternative fuels then the pollution and disease will decline and the pressure on fossil fuels, of course, will decrease. The advantages to use alternative fuels are massive. The impact of alternative fuels can have on earth, on people, on so many things is just great.
Using alternative fuels can change a lot of things on earth a pollution free place.
Here are some possible alternative means of propulsion for road vehicles.
5. Natural Gas
Biodiesel is a fuel made by chemically reacting alcohol with vegetable oils, fats or greases, such as recycled restaurant greases. It is most often used in blends of two percent or 20 percent (B20) Biodiesel. It can also be used as neat Biodiesel (B100). Biodiesel fuels are compatible with and can be used in unmodified diesel engines with the existing fuelling infrastructure. It is the fastest growing alternative transportation fuel in the U.S.
Biodiesel contains virtually no sulphur, so it can reduce sulphur levels in the nation’s diesel fuel supply. Removing sulphur from petroleum based fuel results in poor lubrication. Biodiesel is a superior lubricant and can restore the lubricity of diesel fuel in blends of only one or two percent. Biodiesel can also improve the smell of diesel fuel, sometimes smelling like French fries.
B100 and Biodiesel blends are sensitive to cold weather and may require special anti-freeze, as petroleum-based diesel fuel does. Biodiesel acts like a detergent additive, loosening and dissolving sediments in storage tanks. Because Biodiesel is a solvent, B100 may cause rubber and other components to fail in vehicles manufactured before 1994. Using B20 minimizes these problems.
Biodiesel is renewable, safe, and biodegradable, and reduces serious air pollutants such as particulates, carbon monoxide, hydrocarbons, and air toxics. Emissions of nitrogen oxides, however, increase slightly with the concentration of Biodiesel in the blend.
Biodiesel’s fuel characteristics exceed those of petroleum-based diesel in cetane number, resulting in superior ignition. Therefore, Biodiesel has a higher flash point, making it more versatile where safety is concerned. Horsepower, torque, and fuel economy are comparable to diesel.
Benefits of Biodiesel Use:
• Biodiesel Displaces Imported Petroleum.
• Biodiesel Reduces Emissions.
• Biodiesel Improves Lubricity.
• Biodiesel is Easy to Use.
Average emission impacts of Biodiesel fuels in CI engines
Drawbacks of Biodiesel Use:
Biodiesel contains 8% less energy per gallon than typical No. 2 diesel in the United States; 12.5% less energy per pound. The difference between these two measurements is caused by the fact that Biodiesel is slightly denser than diesel fuel, so there are slightly more pounds in a gallon of fuel. All Biodiesel, regardless of its feedstock, provides about the same amount of energy.
Safety, Health and Environmental Issues:
Biodiesel contains no hazardous materials and is generally regarded as safe to use. Like any fuel, certain fire safety precautions must be taken. Appendix III contains a Material Safety Data Sheet (MSDS) with details on concerns in these areas. A number of studies have found that Biodiesel biodegrades much more rapidly than conventional diesel. Users in environmentally sensitive areas such as wetlands, marine environments, and national parks have taken advantage of this property.
In 1891, William Morrison of Des Moines, Iowa, developed the first electric car. By the turn of the century, dedicated electric vehicles (EVs) outnumbered their gasoline-powered counterparts by two-to-one. Today there are about 10,500 dedicated EVs in use in the United States, mostly in the West and South. Researchers are still working on the same problem that plagued those early dedicated EVsan efficient battery.
Dedicated electric vehicles must have batteries that can be discharged and recharged repeatedly. Since most batteries can’t store large amounts of energy, a dedicated electric vehicle must carry as many batteries as possible. In some dedicated EVs, the batteries constitute almost half the weight of the car. The typical dedicated EV battery pack must be replaced every 20,000 to 30,000 miles, a big expense in itself. Tax incentives can offset some of these costs. The batteries limit the range of a dedicated EV, which is determined by the amount of energy stored in its battery pack. The more batteries a dedicated EV can carry, the more range it can attain, to a point. Too many batteries can weigh down a vehicle, reducing
its load-carrying capacity and range, and causing it to use more energy. The typical dedicated EV can only travel 50 to 130 miles between charges. This driving range assumes perfect driving conditions and vehicle maintenance. Weather conditions, terrain, and some accessory use can significantly reduce the range.
Dedicated EVs, therefore, have found a niche market as neighborhood or low speed vehicles for consumers going short distances at speeds of 30 mph or less. The batteries used in EVs today include lead-acid, NiCad, NiMH, nickel iron, and nickel zinc. Extensive research is being conducted on advanced batteries that will increase electric vehicle range. Some of these batteries are scaled-up versions of the batteries used in portable computers. Such advanced batteries could double the current range of electric vehicles, and hold promise for being longer lived.
Dedicated electric vehicles produce no tailpipe emissions, but producing the electricity to charge them can. EVs are really coal, nuclear, hydropower, oil, and natural gas cars, because these fuels produce most of the electricity in the U.S. Coal alone generates more than half of our electricity. When fossil fuels are burned, pollutants are produced like those emitted from the tailpipe of a gasoline-powered automobile. Power plant emissions, however, are easier to control than tailpipe emissions. Emissions from power plants are strictly regulated, controlled with sophisticated technology, and monitored continuously. In addition, power plants are usually located outside major centers of urban air pollution.
The low maintenance of dedicated electric vehicles is appealing to many consumers. Dedicated EVs acquire no tune-ups, oil changes, water pumps, radiators, injectors, or tailpipes. And no more trips to the service station. Dedicated EVs can be refueled at home at night, when electric rates are low, making the fuel cost comparable to or lower than gasoline. There are also more than 600 refueling stations, mostly in California and Arkansas.
HEVS HYBRID ELECTRIC VEHICLES:
Hybrid Electric Vehicles (HEVs) may be the best alternative vehicle for the near future, especially for the individual consumer. HEVs offer many of the energy and environmental advantages of the dedicated electric vehicle without the drawbacks. Hybrids are powered by two energy sources an energy conversion unit (such as a combustion engine or fuel cell) and an energy storage device (such as battery, flywheel, or ultra capacitor). The energy conversion unit can be powered by gasoline, methanol, compressed natural gas, hydrogen, or other alternative fuels. HEVs have the potential to be two to three times more fuel-efficient than conventional vehicles. HEVs can have either a parallel or series design. In a parallel design, the energy conversion unit and electric propulsion system are connected directly to the vehicle’s wheels. The primary engine is used for highway driving; the electric motor provides added power during hill climbs, acceleration, and other periods of high demand. In a series design, the primary engine is connected to a generator that produces electricity. The electricity charges the batteries and drives an electric motor that powers the wheels. Hybrid power systems were designed as a way to compensate for the limitations of dedicated EVs. Because batteries can only supply power for short trips, a generator powered by an internal combustion engine was added to increase range. A HEV can function as a purely electric vehicle for short trips, only using the internal combustion engine when longer range is required. HEVs on the market today combine an internal combustion engine with a battery and electric motor, resulting in vehicles with twice the fuel economy of conventional vehicles. Depending on driving conditions, one or both are used to maximize fuel efficiency and minimize emissions, without sacrificing performance. An HEV battery doesn’t have to be recharged. It has a generator powered by the internal combustion engine to recharge the batteries whenever they are low. A regenerative braking system captures excess energy when the brakes are engaged. The recovered energy is also used to recharge the batteries.
The HEV provides extended range and rapid refueling, as well as significant environmental benefits, reducing pollutants by one-third to one half. Their range and fuel economy will make them attractive to consumers as more models become available to meet their needs.
History of Ethanol:
Ethanol is not a new product. It was widely used before the Civil War. In 1908, Henry Ford designed his Model T to run on a mixture of gasoline and alcohol, calling it the fuel of the future. In 1919, the ethanol industry received a blow when Prohibition began. Since ethanol was considered liquor, it could only be sold when it was denatured rendered poisonous by the addition of petroleum components. With the end of Prohibition in 1933, interest in the use of ethanol increased.
Ethanol as a Fuel:
In the 1970s, the oil embargoes revived interest in ethanol as an alternative fuel. Today, more than fifty ethanol plants, mostly in the Midwest, produce over a billion gallons of ethanol. Gasoline containing ten percent ethanolE10is widely used in urban areas that fail to meet standards for carbon monoxide and ozone. Since ethanol contains oxygen, using it as a fuel additive results in up to 25 percent fewer carbon monoxide emissions than conventional gasoline. E10 is not considered an alternative fuel under EPACT, but a replacement fuel. There are about three million vehicles on the road today using ethanol blends. Vehicles are not converted to run on E85, they are manufactured. Flexible fuel vehicles (FFV) are designed to use any combination of ethanol and gasoline up to 85 percent ethanol. E85, a fuel that is 85 percent ethanol and 15 percent gasoline is used mainly in the Midwest and South. There are about 150,000 light-duty vehicles using this fuel, serviced by ethanol fueling stations. Nearly half of these are private vehicles; the rest are federal, state and local government fleet vehicles. The cost of E85 is equivalent to mid-grade gasoline. The fueling process for E85 is the same as for gasoline, however, vehicle range is about 15 percent less. With an octane rating of 100, power acceleration, payload capacity, and cruise speed are comparable to gasoline. Maintenance is also similar. Ethanol is made from domestic, renewable feed stocks. It can reduce U.S. dependence on foreign oil. Using ethanol can also reduce carbon monoxide and carbon dioxide emissions. Ethanol is made from crops that absorb carbon dioxide and give off oxygen. This carbon cycle maintains the balance of carbon dioxide in the atmosphere when using ethanol as a fuel. As new technologies for producing ethanol from all parts of plants and trees become economical, the production and use of ethanol should increase dramatically.
Natural Gas (CNG/LNG)
The natural gas we use for heating, cooking, clothes drying, and water heating can also be a clean burning transportation fuel when compressed or liquefied. Natural gas vehicles burn so cleanly that they are used to carry TV cameras and reporters ahead of the runners in marathons. Natural gas is a nonrenewable fossil fuel with plentiful supplies in the United States. Its chemical formula is CH4.
CNG- COMPRESSED NATURAL GAS
Natural gas is usually placed in pressurized tanks when used as a transportation fuel. Even compressed to 2,400-3,600 pounds per square inch (psi), it still has only about one-third as much energy per gallon as gasoline. As a result, natural gas vehicles typically have a shorter range, unless additional fuel tanks are added, which can reduce payload capacity. With an octane rating of 120+, power, acceleration and cruise speed are comparable. Today, there are about 144,000 CNG vehicles in operation in the U.S., mostly in the South and West. About half are privately owned and half are vehicles owned by local, state, and Federal government agencies. Vehicles manufactured to run on CNG are available from several manufacturers. A gasoline engine can also be converted to run on CNG at a cost of $2,000-3,000, depending on the number of fuel tanks installed. The lower price of natural gas and tax incentives can help offset the cost of conversion.
Some people are concerned about the safety of using CNG as a fuel. CNG tanks are designed for high pressures; they are many times stronger than normal gasoline tanks. It is much less likely that CNG fuel tanks will be damaged in vehicle crashes than the typical gasoline tank. Additionally, if a fuel line is accidentally severed, the natural gas that is released rises and disperses, unlike gasoline, which forms puddles. Natural gas also ignites at a much higher temperature than gasoline (1,200o Fahrenheit compared to 800o Fahrenheit), making accidental combustion of natural gas less likely. The production and distribution system for natural gas is in place, but the delivery system of stations is not extensive. Today, there are about 1,250 natural gas refueling stations in the United States, considerably less than the multitude of gasoline stations. CNG refueling stations are not always at typical gasoline stations, may not be conveniently located, and some have limited operating hours. Natural gas vehicles are well suited to business and public agencies that have their own refueling stations. Many fleets report two to three years longer service life, because the fuel is so clean-burning.
Compressed natural gas (CNG) vehicles emit 85-90 percent less carbon monoxide, 10-20 percent less carbon dioxide, and 90 percent fewer reactive non-methane hydrocarbons than gasoline-powered vehicles. (Reactive hydrocarbon emissions produce ozone, one of the components of smog that causes respiratory problems.) These favorable emission characteristics result because natural gas is 25% hydrogen by weight; the only combustion production of hydrogen is water vapor.
LNG- LIQUEFIED NATURAL GAS:
There are also about 3,100 vehicles in the U.S. that run on LNG that is liquefied by cooling to 259OF. Most LNG vehicles are government-owned; there are less than 100 LNG-fueling stations at this time. The advantage of LNG is that natural gas takes up much less space as a liquid than as a gas, so the tanks can be much smaller. The disadvantage is that the fuel tanks must be kept cold, which uses fuel.
Propane is an energy-rich fossil fuel often called liquefied petroleum gas (LPG). It is colorless and odorless; an odorant called mercaptan is added to serve as a warning agent. Propane is a by-product of petroleum refining and natural gas processing. And, like all fossil fuels, it is nonrenewable. The chemical formula for propane is C3H8. Under normal atmospheric pressure and temperature, propane is a gas. Under moderate pressure and/or low temperature, however, propane can easily be changed into a liquid and stored in pressurized tanks. Propane is 270 times more compact in its liquid state than it is as a gas, making it a portable fuel.
HOMES AND BUSINESS:
Homes and businesses use about one-third of the propane consumed in the U.S. Propane is used mostly in rural areas that do not have natural gas service, as well as in manufactured (mobile) homes. Homes that use propane as a main energy source have a large propane tank either above or below ground that holds between 5001,000 gallons of liquid fuel. Dealers deliver propane to the residences in trucks, filling the tanks several times a year. Propane is used in homes for air conditioning, heating water, cooking and refrigerating foods, drying clothes, lighting, and fueling fireplaces. Millions of backyard cooks use gas grills for cooking. And recreational vehicles (RVs) usually have propane-fueled appliances. More than a million businesses such as hotels, schools, and restaurants use propane for heating and cooling, cooking and refrigerating food, heating water, and lighting.
Propane-fueled engines produce less air pollution than gasoline engines. Carbon monoxide emissions from engines using propane are 50 to 92 percent lower than emissions from gasoline-fueled engines. Hydrocarbon emissions are 30 to 62 percent lower. Why is propane not more widely used as a transportation fuel? The infrastructure for distributing propane is in place across the country, but it is not as conveniently available as gasoline. In 2004, there were about 3,500 LPG vehicle-fueling stations in the U.S., which cost about the same to build as gasoline stations. Second, a conventional automobile engine has to be converted to use propane fuel, at a cost of approximately $2,500.
Out of all the alternative fuels available today, the alternative fuel which I consider to be the system for the most potential is “THE HYDROGEN FUEL CELLS”. Given below is the clear description of the hydrogen fuel cell which supports my statement.
HYDROGEN FUEL CELLS
In the future, hydrogen may provide a significant contribution to the alternative fuel mix. The space shuttles use hydrogen for fuel. Fuel cells use hydrogen and oxygen to produce electricity without harmful emissions; water is the main by-product. Hydrogen is a gas at normal temperatures and pressures, which presents greater transportation and storage hurdles than liquid fuels. No distribution system currently exists.
Hydrogen is the most abundant element in the universe, but it doesn’t exist on Earth as a gas; it is produced by two methods electrolysis and synthesis gas production from steam reforming or partial oxidation. Electrolysis uses electricity to split water molecules into hydrogen and oxygen. The Department of Energy does not expect electrolysis to be the predominant method of producing large quantities of hydrogen fuel.
Today, the predominant method of producing hydrogen is steam reforming of natural gas, although biomass and coal can also be used as feed stocks. High production costs have limited hydrogen as a fuel to date except in research vehicles, but research is progressing on more efficient ways to produce and use it. The largest drawback to widespread vehicle use will be storage the lower energy content of hydrogen requires fuel tanks six times larger than gasoline tanks. Its environmental benefits, however, mean that in 20 years, hydrogen fuel cell vehicles may be a common sight on the roadways of America.
The Bush administration has launched a hydrogen fuel cell initiative to further research and development of this promising technology.
Fuel Cells Offer Significant Improvements in Energy Efficiency and Emissions:
Fuel cells represent a radically different approach to energy conversion, one that could replace conventional power generators like engines, turbines, and batteries in applications such as automobiles, power plants, and consumer electronics. Fuel cells, like batteries, directly convert chemical energy into electric power. But unlike batteries, fuel cells do not need recharging; instead they use fuel to produce power as long as the fuel is supplied. Fuel cells operate quietly and are relatively modular. Largely because of these characteristics, hydrogen-powered fuel cells promise:
1. For vehicles, over 50% reduction in fuel consumption compared to a conventional vehicle with a gasoline internal combustion engine.
2. Increased reliability of the electric power transmission grid by reducing system loads and bottlenecks.
3. Increased co-generation of energy in combined heat and power applications for buildings
4. Zero to near-zero levels of harmful emissions from vehicles and power plants
5. High energy density in a compact package for portable power applications
STATUS OF HYDROGEN TODAY:
Although hydrogen is the most abundant element in the universe, it does not naturally exist in its elemental form on Earth. Pure hydrogen must be produced from other hydrogen-containing compounds such as fossil fuels, biomass, or water. Each method of production requires a source of energy, i.e., thermal (heat), electrolytic (electricity), or photolytic (light) energy. Hydrogen is either consumed on site or distributed to end users via pipelines, trucks, or other means. Hydrogen can be stored as a liquid, gas, or chemical compound and is converted into usable energy through fuel cells or by combustion in turbines and engines. Fuel cells now in development will not only provide a new way to produce power, but will also significantly improve energy conversion efficiency, especially in transportation applications.
LPG omitted because it scales the graph so trends of the other fuels are obscured.