Cultural Revolutionary

?Alternative Fuels: A Realistic Alternative for Petroleum or Just Hype?
Author: Rick Waite

Recently in the media and public eye Petroleum had once again come under fire as it has in the past. One of the alternatives to petroleum based fuels that has been advanced is to use alternative fuels as a source of energy for automobiles and truck. But are alternative fuels actually an economical and practical substitute for gasoline and diesel fuel that is currently being used? Answering that question can be harder than it first seems. Most sources of information on the subject seem to have their own agenda to support and only disseminate information that supports their claims. After examining some of the sources of information that is available the only conclusion I can come to is that there is no clear alternative. No one alternative fuel seems to be the magic bullet that will kill off the monster petroleum.
I think before any examination of alternative fuels can be carried out the current debate against traditional fossil based fuels should be examined. Some of the arguments against it have been heard before such as supplies are running out and it is too expensive. However, recent events have added new fuel to the fire. More attention is being paid to claims that emissions from fossil fuels are raising atmospheric concentrations of the greenhouse gas carbon dioxide. While many say it has yet to be proven, proponents of this theory say that elevated levels of carbon dioxide will cause global warming, melting of the polar ice caps which will cause the level of the sea to rise flooding coastal areas, and global climate change. Other sources say that the Earth’s climate is not inherently stable and is changing on its own or that humanity cannot change anything as large as the global climate. In addition to the economic and environmental factors is the political reality that most of the worlds petroleum reserves are located in areas of the world that are hostile to the interests of the United States. The idea that hundreds of millions of dollars are being drained out of the US economy and sent overseas to the Middle East is growing more and more unpleasant every day. The fact is that the US is subsidizing Middle Easterners that run training centers for terrorists, pay bounties to suicide bombers, fund purchases of weapons and explosives, and underwrite new media outlets that propagandize hatefully against the United States and Western Civilization (Zubrin).
Regardless of the cause there is a growing groundswell of public and political demand for more use of so called “Alternative fuels” defined in Wikipedia as non-conventional fuels, any material or substance that can be used as a fuel, other than fossil fuels, or conventional fuels of petroleum (oil), coal, propane, and natural gas. The term “alternative fuels” usually refers to a source of energy which is renewable (“Alternative Fuel”).
When most people think of a motor vehicle propelling itself down a road while producing no pollution the first source of energy they think of is usually electricity. Some of the perceived benefits of electricity are that there is no pollution from the vehicle (zero emissions). Electric vehicles are generally quieter than their gasoline powered counterparts, and because they do not need a transmission and associated drive train, they have fewer moving parts to replace or repair (“Alternative Fuels Data Center”). But all is not sunshine and flowers in the land powered by electric vehicles. Electric vehicles have a short un-refueled range when compared to conventional automobiles. The batteries in an electric vehicle also must be replaced every three to five years. And one of the most neglected factors in the electric vehicle equation is that there must be a source of electricity to recharge the batteries. With most of the nation’s power grid already operating at near capacity as evidenced by annual black and brownouts in major population centers where is the billions of kilowatts going to come from to power fleets of electric cars? Even if much of the available countryside was to be carpeted with solar cells and wind generators most of those electrons would undoubtedly come from good old fossil fueled power plants. So is the reality of electric vehicles just pollution relocation from the tailpipe to the smokestack? Who will foot the bill for the cost of billions of dollars to build the additional generating capacity and recharging stations? An alternative though to running electric vehicles with batteries is to use fuel cells powered by hydrogen.
Hydrogen as fuel seems to be the Holy Grail for some environmentalists. They point to the fact that when hydrogen is burned the only byproduct is heat and water and that hydrogen can be produced using a variety of domestic resources such as biomass, coal, electrolysis with water, and natural gas. The two main avenues to power a vehicle with hydrogen are through the use of fuel cells or by burning it in a traditional internal combustion engine. When hydrogen is burned in an internal combustion engine the only pollution at the tailpipe is a slight amount of oxides of nitrogen (NOx) with claim that it is about 30% more efficient than an equivalent engine powered by gasoline (“Fact Sheet: Hydrogen Fuel: A Clean and Secure Energy Future”). BMW will be making a hydrogen powered version of its 7 series sedan available to loan for select people in 2007. The Hydrogen 7 is powered by a modified version of the companies 435 horsepower v12 engine that running on liquid hydrogen fuel produces 260 hp but only has a range of 125 miles. Once the hydrogen is used up the driver can push a button and switch over to gasoline and go an additional 300 miles. (”High on Hydrogen” 25)
Most proponents of hydrogen as a fuel point to its use in fuel cells as the preferred method of extracting energy from hydrogen however. A fuel cell is a device that electrochemically converts hydrogen and oxygen from the atmosphere into electricity and water vapor. Using a fuel cell to provide the energy for an electric vehicle can provide much greater range and flexibility than just a storage battery alone. Unfortunately fuel cells still have some issues that need to be worked out. They are about 3 times as expensive as an equivalent internal combustion power plant. In colder areas of the country fuel cells need to be pre-heated before they will work. If used to power the vehicle solely they exhibit poor “throttle response”, and it is still difficult to find a refueling station that offers liquid hydrogen to refuel them.
That covers using hydrogen as a fuel but how difficult and efficient is it to manufacture? Hydrogen is not a source of energy. It is a carrier of energy. Hydrogen must be made either through the electrolysis of water, or breakdown of natural gas, coal, alcohol, or other hydrocarbon. When hydrogen is freed from water by electrolysis the process is only 85% efficient. When that hydrogen is used to feed a fuel cell it returns about 55% of that energy as electricity with the loss as waste heat and other inefficiencies. The result of this is only about 47% of the energy that went into creating the hydrogen is recovered to power the vehicle. If the hydrogen is utilized to fuel an internal combustion engine instead, the efficiency drops to around 25%. The most common and economical way to produce hydrogen is through steam reforming of natural gas. Unfortunately most of the pollutants that would be created by burning the natural gas are created as waste in this process also. In this process though, 40 to 60 percent of the energy in the natural gas is lost thereby increasing the need for fossil fuels and resultant emissions 40 to 60 percent to make up for the loss. One mole of hydrogen gas (6.0221415×1023 atoms) when reacted with oxygen yields 66 watt-hours of energy. The same quantity of methane (a primary component of natural gas) produces 218 watt-hours of energy. A car fueled by methane with the same size fuel tank as a hydrogen powered vehicle would travel over three times as far on cheaper fuel and release fewer total emissions (Zubrin).
Alcohol, both ethanol and methanol, are both commonly considered an economical alternate fuel. Ethanol is an alcohol produced by fermentation and distillation of starch crops. It can also be produced from “cellulosic biomass” such as trees and grass and is called bioethanol. Cellulosic ethanol can even be made from forest products and construction waste and may yield a higher energy balance than ethanol made from corn. This ethanol is blended with gasoline at either 85% (E85) or 95% (E95) concentrations of alcohol to gasoline. This can then be used as a motor fuel in internal combustion engines but they must be specially modified to run on it as the energy content is much lower than gasoline. These vehicles that have been designed to use this fuel are called flexible fuel vehicles (“Alternative Fuels Data Center”).
Wood alcohol, also known as Methanol, is similar to Ethanol in that using it as a motor fuel can result in lower emissions at the tailpipe and higher performance. An additional benefit is that Methanol has a lower flammability than gasoline so it can be a bit safer in case of an accident. Other benefits of methanol are that it can be easily converted to hydrogen for use in fuel cells. Also it can be easily manufactured from carbon based feed stocks such as natural gas, coal and biomass (“The Future of Alternative Fuels”).
Wood alcohol is unfortunately most commonly and economically made from natural gas by a process known as steam reformation. Using this process to create an alternative fuel has the side effect of releasing large amounts of greenhouse gases. More so than if the natural gas was utilized as a fuel because of the energy lost in the process. Another problem with Methanol as it is highly corrosive to aluminum, a metal very common to vehicle fuel and refueling systems. Any vehicles or systems used to refuel them would have to be suitably modified to take the corrosive factors into account (“Alternative Fuels Data Center”).
More recently biodiesel has been gaining a lot of attention as a alternative motor fuel. Biodiesel is a renewable fuel that can be manufactured from many domestically produced sources such as vegetable oils, animal fats, and restaurant greases. Blends as high as 20% biodiesel mixed with conventional diesel fuel can be used in unmodified diesel engines and reduces carbon dioxide emissions by about 15%. One hundred percent biodiesel may be used in some engines with little or no modification. However, engine manufacturers are concerned long term engine durability will be reduced. Other benefits of biodiesel are that using it greatly reduces emissions of unburned hydrocarbons, carbon monoxide, sulfates, and particulate matter (soot) and the fact that no modification to current diesel fuel refueling networks is necessary to utilize it. Biodiesel is also safer than regular diesel fuel in that it is much less combustible making it safer to handle, store, and transport (“The Future of Alternative Fuels”).
Unfortunately at current levels there is only enough feedstock to supply about 1.9 billion gallons of biodiesel per year. This would only replace about 5% of on road diesel fuel use in the United States. Other factors are that it has been shown to negatively impact the durability of many diesel engines and as it has poorer low temperature characteristics than standard diesel fuel so it may not be suitable for wintertime use (“Alternative Fuels Data Center”).
As the demand for energy increases in the United States and concern grows over greenhouse gas emissions and the increasing cost of fossil fuels, new sources of energy will need to be found. Also in the current political climate it is getting increasingly unsavory to many people in this country to see the huge amount of money being transferred to hostile Middle Eastern countries. However most of these alternative fuels at the best need more research before they can be reliably and economically used. In the worst case some of these alternative fuels seem need more energy to create than they return and may actually cause more emissions than the fuels they are supposed to replace!