EGEE 101
Energy and the Environment

Alternative Fuels

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By now you should have a good grasp that traditional transportation causes pollution. There is also a supply issue with the source of the gasoline and diesel. We now produce nearly all of our own crude oil. But that is new. We had traditionally been reliant on foreign imports. This is why this unit contains the security lecture (Gulf War?) Now the main driving force is pollution control.

We can use alternative fuels to achieve reduced (or elimination) pollution and enhanced national security and balance of trade. They can be encouraged by using mandates such as renewable portfolio standards (x% of the diesel sold will be biodiesel for example) or by using feed-in tariffs (the fist X5 of biodiesel will get this high price). There are a variety of fuels to choose from:

Ethanol

Ethanol is a chemical compound we have already discussed as an oxygenate to reduce pollution from gasoline. But it can also be a fuel in its own right. You know ethanol as alcohol. The same compound is in beer and wine and is responsible for the intoxication effects.

A methanol and ethanol fuel pump.
Perhaps ethanol and possibly methanol will be common at the petrol station sometime in the near future.
Credit: NREL

The CH3CH2OH formula is important. If you drink enough methanol CH3OH, your retina will detach and you go blind (all because a CH2 is missing). The OH (that is the alcohol unit) also enables ethanol to be a liquid at the same conditions that ethane (CH3-CH3) is a gas. The liquid fuels are easier to handle and store than the gas version. Which is easier to carry: a gasoline container or a pressurized propane tank? You also need to know there is far more energy in the gasoline–if comparing similar volumes. This is one of the major problems with gaseous fuels - storage has to be in pressurized containers, which increases the mass. Why is mass important? And it increases the cost (thick steel is more expensive.)

Ethanol is a biomass fuel. This means that we can grow the energy without being required to import crude oil. There are many states where we can grow corn, and this would help employment in agriculture, particularly in the "corn belt" of the mid-West. It is also used for animal feed and its use as a fuel source means pork prices goes up. This is a problem for countries with large poor populations such as South America (there have been corn tortilla riots!) The greenhouse gas savings are also in question.

A hand full of bagasse (looks like small pieces of hay).
Bagasse is another biomass fuel from sugar cane. The sugar juices are extracted and the remaining plant material is dried and the Bagasse is then used as a fuel.
Credit: NREL

There are other ways of producing ethanol, it need not just be from corn. In warmer climates, sugarcane would be the appropriate choice. In Brazil, they grow sugarcane and use it to produce ethanol. The ethanol is used in an ethanol and gasoline mixture (97 % ethanol) to fuel their vehicles.

Why do Brazilians add gasoline to the mixture?

Please watch the following (:21) video. Why Add Gasoline? Click for text description. This will expand to provide more information.

There is only one good reason to add gasoline to perfectly good ethanol and that is to render it undrinkable. Pure ethanol is essentially drinkable. It's actually not very good for you. I've certainly handled restricted compounds in my career as a chemist and I have to follow the same rules and regulations, pretty much, for 96% ethanol as I did for 99.99% cocaine. That's in pure levels of course. But it is one of these things that you do not want the population literally drunk driving while their cars have been drinking as well. You can just imagine a situation where with one very long straw, drunk driving comes to a whole new level of incompetence. So essentially the 3% gasoline is simply to stop it from being one for you, one for me, one for you, one for me at the pump.

"Mathews in the corn" sounds like a good movie title. (Is it me, or does it look like he's been in that corn way too long...?)
Click for a transcript.

[Video opens with Dr. Mathews standing in front of a cornfield.] Dr. Mathews: The nice thing about biomass, of course, is that it recycles carbon dioxide back into the atmosphere. This is corn. Although most of it is used for animal feed, they are associated with a great deal with food. The other thing you could do with it is either take this corn and directly burn it or you could distill it into alcohol and use that alcohol as a transportation fuel. [Video ends.]

Dr. Mathews

The use of a liquid fuel has major advantages because the infrastructure is in place already. We may have to change the hoses on the pumps or else some of the liquid fuels will dissolve them, but these issues are minor.

Compressed Natural Gas

We have seen natural gas in CATA buses and in some of the OPP (Office of Physical Plant) trucks that park on the pavement (sidewalk) around campus. The average automobile can be converted to run on compressed natural gas (CNG) for about $2,000 so it is not cheap. There is less wear on the engine and less maintenance is needed. Most of our methane is domestic and there is the potential for making more via synthesis gas chemistry. Methane is a greenhouse gas, (more in Lesson 11 on that issue) and the cost of methane can vary with seasonal demand (as does gasoline). If methane was cheaper (for the same mileage) I think more of us would be using it as a fuel. All the alternatives are more expensive than gasoline. This is now popular with fleet vehicles.

a line of vans in a parking lot
Fleet vehicles are the logical starting place for alternative fuels. A central fueling station, high mileage vehicles, little impact on the (voting) public, and it is a Federal Law that companies with a fleet must have a certain % of their vehicles fueled by alternative fuels (more in Lesson 09). The federal government is leading the way with significant percentages of their fleet being alternative fuel vehicles.
Credit: JPM
A small truck which has been converted to run on natural gas.  There is a sign on the side that says it runs on natural gas.
This Pennsylvanian Department of the Environment vehicle has been converted to run on natural gas. How can you tell? (Other than the sign on the side!) An additional fuel cap has been added.
Credit:JPM
A methane gas detector which will sound an alarm if a leak is detected.
We drive every day sitting above (more or less) a gasoline tank without a second thought. There is a public perception challenge to the use of alternative vehicles. The CATA buses have a methane gas detector to provide an audible alarm in case of a natural gas leak.
Credit: JPM

Missing from this listing are electric vehicles and biodiesel. Propane is also a potential fuel that is being used in some fleet vehicles. More on this later.

Image showing alternative fuel pumps (compressed natural gas etc.).
Various alternative fuel "pumps" for refueling.