Alternative Fuels

Do we need nonrenewable, polluting juels. ? There are alternatives.

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Greenhouse Gases Threaten Planet

Alternative Fuels
Biodiesel
Ethanol
Hydrogen
Water in fuel blends

 Alternative Fuels in this context refers to  any fuel that can be, but is not currently widely used in the transportation industry. These fuels can consist of nearly any combustible material.  We will list some of the more widely recognized alternative fuels with some basic information on where and how they are derived. Then we will look  at what would be the best choises for the environment and economic viability. The following list is not in any order, nor is their inclusion an endorsement. In fact some of the fuels listed offer little advantage over the current petroleum system. Their inclusion is for  informational purposes so that the reader may gain a more complete understanding of the fuels that are being promoted to replace petrol.

 

Propane/LPG

"Liquefied petroleum gas (LPG), as the name suggests, is partly a byproduct of petroleum refining; in California the state's oil refineries are the main source, but nationwide only about 45% of LPG comes from petroleum refining, and the majority comes from natural gas processing. LPG consists of hydrocarbons, which are gases at room temperature, but turn to liquid when they are compressed. LPG is stored in special tanks that keep it under pressure, so it stays a liquid. The pressure of these tanks is usually about 200 pounds per square inch (abbreviated "psi"). The main constituent of LPG is propane; the name by which it is often referred to.

Because LPG enters the engine as a vapor, it doesn't wash oil off cylinder walls or dilute the oil when the engine is cold, and it also doesn't put carbon particles and sulfuric acid into the oil. Thus an engine that runs on propane can expect a longer service life and reduced maintenance costs. LPG is also cheaper than gasoline in most places."

http://www.phillycleancities.org/altfuels.htm 

An overview of a conversion to propane can be found here.

   http://science.howstuffworks.com/lpg5.htm

 

Compressed Natual Gas 

"Natural gas comes from underground and is made up of around 95% methane. Methane is a hydrocarbon, meaning its molecules are made up of hydrogen and carbon atoms. Its simple, one-carbon molecular structure (CH4) makes possible its nearly complete combustion. The remaining 5% is made up of various gases along with small amounts of water vapor. These other gases include butane, propane, ethane and other trace gases.

Cars, vans, buses and small trucks generally use natural gas that has been compressed (hence the name compressed natural gas or CNG) and stored in high-pressure cylinders. Alternatively, gas may be compressed by the dispenser unit for overnight fueling.  The practically complete combustion ensures CNG is an extremely clean burning fuel unlike gasoline or diesel."

http://www.phillycleancities.org/altfuels.htm  

 

Liguified Natural Gas

"Liquefied natural gas (LNG) is made by refrigerating natural gas to minus 260 degrees Fahrenheit (260 degrees below zero!) to condense it into a liquid. This process removes most of the water vapor, butane, propane, and other trace gases, that are usually included in ordinary natural gas. The resulting LNG is usually more than 98 percent pure methane.

The liquid form is much more dense than natural gas or CNG. It has much more energy for the amount of space it takes up. So, much more energy can be stored in the same amount of space on a car or truck. That means LNG is good for large trucks that need to go a long distance before they stop for more fuel."

   http://www.phillycleancities.org/altfuels.htm 

 

  The  natural gas  vehicle forum

http://www.ngv.org/ 


Methanol

"Methanol requires few if any engine modifications to extract the maximum power from this fuel. As compared to gasoline, methanol lowers some tailpipe emissions, namely the sulphur based HC, CO, as well as NOx. Methanol contains only half the energy per gallon of gasoline but has a very high octane rating. Increased compression ratios could yield 5 to 20 percent more power. Methanol can be produced from natural gas or from wood fiber. When made from natural gas, production costs are competitive; when made from wood fiber, production costs almost double. Production of methanol from coal and biomass, while possible in the laboratory, has not been economically demonstrated in a mass production process. When methanol is used as a gasoline additive, antiknock compound and fuel extender, it becomes economical with very positive results, especially from the emissions standpoint. It contains zero sulfur, thereby reducing tailpipe acids significantly. Of the six most popular alternative fuels presently available, methanol has the second lowest Btu/lb. net energy yield. As a result, fuel tanks will need to be enlarged for vehicles that run on pure methanol or driving range between refills will be reduced in half."

http://www.leeric.lsu.edu/bgbb/7/ecep/auto/m/m.htm 

Methanol causes exessive corrision to engine parts according to some reports.

 

Ethanol 

 "Ethanol is made by fermenting and then distilling starch and sugar crops -- maize, sorghum, potatoes, wheat, sugar-cane, even cornstalks, fruit and vegetable waste."

"Ethanol is also a high-performance motor fuel that cuts poisonous exhaust emissions and is better for the environment."

"Chrysler, Ford, and General Motors all recommend ethanol fuels, and nearly every car manufacturer in the world approves ethanol blends in their warranty coverage.

Over two trillion miles have been driven on ethanol-blended fuels in the US since 1980. "

http://journeytoforever.org/ethanol.html 

 

Biodiesel 

 "In 1895, Dr. Rudolf Diesel developed the “diesel” engine with the intention of running it on a variety of fuels, including vegetable oil. In fact, when Diesel demonstrated his engine at the World Exhibition in Paris in 1900, he used peanut oil as fuel. Since that time, however, the diesel engine has been modified to run on petroleum-derived fuel (petrodiesel) because historically it was the least expensive fuel available. Today, the diesel engine is still capable of running on “biodiesel” fuel, which can be produced from a variety of renewable sources, including soybean oil, canola oil, sunflower oil, cottonseed oil, and animal fats. These sources can be obtained from agricultural feedstocks or by recycling used oil such as cooking grease. Most biodiesel produced in the United States is made from soybean oil due to this feedstock’s abundance. Biodiesel is usable in its pure form,
known as “neat biodiesel” or B100. In addition, it is available in various blends with petrodiesel, the most common of which is known as B20 (20 percent biodiesel and 80 percent petrodiesel). It is also used in smaller percentages as a lubricating fuel additive."

http://www.naftc.wvu.edu/technical/factsheets/biodfactsheetepa.pdf 

Electric 

"Electric vehicles (EV's) are generally divided into battery and hybrid classes. Hybrid electric vehicles can be designed to run on any fuel, including gasoline or diesel as well as alternative fuels. Hybrids are self-contained units for maximum efficiency - when engine demand is low (starting, stopping) hybrids are powered by an electric motor, during normal traveling the gasoline engine engages, and when decelerating or braking the wheels drive he electric motor, which acts as a generator and recharges the battery.

Battery-electric vehicles don't burn gasoline in an engine, they use electricity stored on the car in batteries. Sometimes, 12 or 24 batteries, or more, are needed to power the car. Just like a remote-controlled model electric car, EV's have an electric motor that turns the wheels and a battery to run that motor. To charge an EV's batteries, the car is plugged in to ordinary 110-volt wall sockets and/or 220-volt appliance outlets.  Modern production EV's are mostly being built with specialized connectors that can speed up the "refueling" process and increase safety. You can install a recharging station with the right kind of connector for your vehicle in your garage, and in some cities recharging stations that offer the most popular connectors are being installed in public places."

 http://www.phillycleancities.org/altfuels.htm

At the street level electric cars are completely emmission free and clean. To determine if they are polluting one must look at how the electricity being stored in the batteries was initially generated. If the electricity is produced from hydroelectric, wind generators, or  solar panels , then the electric car is completely nonpolluting. The majority of our electricity in the U. S. is produced by coal burning power plants which are one of the leading causes of green house gases and acid rain.

 

Hydrogen 

 The most abundant element in the universe. The cleanest burning fuel we  can use. Most of the cars on the road today can be converted to run on pure hydorgen. It can be used to generate electricity for an electric car or your home by using it in a fuel cell, or a conventional motorized generator.  Hydorgen can be seperated from water using electrolysis, chemical catalyst and reactant, or a reverse fuel cell.  Power the electrolysis, or reverse fuel cell, with solar voltaic or hydropower and you have a completely non polluting source of energy.

Why is H2 the holy grail of fuels? Let's look at the chemical formulas for some of the other fuels we have considered here.  

  • Propane   C3H8
  • Methane  CH4
  • Methanol CH3OH
  • Ethanol  C2H5OH
  • Gasoline  C8H18
  • Diesel  C12H26

As you can see Hydrogen is a component of each . It is already what powers our transportation system.  It is the inclusion of  C (carbon) that causes most of the greenhouse gases by combining with oxygen during combustion to produce carbonmonoxide and carbondioxide.

 

Conclusions 

These  are the  most promoted alternative fuels.  To make an educated decision on which would be the best alternative you will need to obtain much more information than is offered in this overview.

In making a decision of  which alternatives to offer more infromation on, and to promote on this site, some of the factors that were looked at are:

  • greenhouse gas recuduction compared to traditional gasoline and diesel
  • speed of implimentation on a wide scale
  • adaptability to conventional vehicles  already in use
  • is fuel derived from a renewable resource

   With these factors in mind this site offers Ethanol, Biodiesel, and Hydrogen as the most viable alternatives .  We encourage  you to learn more about, and to  use these alternatives wherever possible, to help reduce greenhouse emissions.