I am not an expert in this area, but just to reiterate what a few people have said, you will find this easier if you narrow your question down to make a feasible science project. There are many companies and government programs focusing on the general question of how best to make ethanol from cellulosic biomass. It's impossible for anyone to answer this big question from a single research project. Instead, people break it down into questions that can be answered by a single project, like this:
1) Which of three plant species (e.g., switchgrass, poplar trees and something else) produce the most sugar (or the most ethanol) when I apply one particular process. (To do this experiment, you will need to find some process that people are already using to extract sugars or ethanol from cellulose, and then apply that process to existing plants. You will also need to use some established technique for measuring the sugars or ethanol.)
2) Which of two or three processes is the most efficient at producing ethanol from switchgrass? (For this experiment, you will need to find some existing processes that produce ethanol from switchgrass. Then you would perform each one, and measure the output from each one.)
3) How can an existing process be adjusted to produce the most ethanol (or sugar) from switchgrass? (For this experiment, you would need to find an existing process of breaking down cellulosic biomass into sugars, and possibly also for converting it into ethanol. Then you would adjust one or two parameters of that process, e.g., temperature and pH, and see which conditions produce the most sugar or ethanol. This experiment could be extended to find the optimal conditions for this process to convert several different plant species, e.g., switchgrass vs. poplar wood chips.)
For all of these, you will probably want to start by finding one process that already works, that you can perform on some available biomass, like switchgrass, straw, pine sawdust, etc. Then you can expand beyond that, to try other plant species, refine the process, or try alternative conversion processes. You can also focus either on getting the most sugar, or getting the most ethanol. It might be easier to just break the biomass down into sugars and measure those, because converting the sugars to ethanol adds a few more steps. For any of these experiments, you will probably need to work with someone nearby with lab space, who can help you set up and run the experiments safely.
Here are some links I found that might help as you go through this:
This google search gives a few useful links:
http://www.google.com/search?&q=cellulo ... ir+project
The first one was about students who used an acid hydrolysis process to break down different types of biomass, and measured how much sugar each one produced:
http://www.usc.edu/CSSF/History/2003/Projects/J0516.pdf
More information on acid hydrolysis can be found through these links:
http://www.google.com/search?q=acid+hydrolysis
http://www1.eere.energy.gov/biomass/dilute_acid.html
I don't know much about this subject beyond what I found from those links. But it looks like acid hydrolysis is well established, and is being used for the first commercial cellulosic ethanol plants. This means it would be a good technique to start with, and then see how well it works with different types of biomass or different operating conditions. Like any chemistry experiment, you need to work with someone experienced who can help you do it safely!
This website also looks like a great background source to see what people are trying and proposing in this area:
http://www1.eere.energy.gov/biomass/
(If you look at the acid hydrolysis article above, you will see that it is part of this website, under Conversion Technologies -> Sugar Platform -> Other Hydrolysis Technologies -> Dilute Acid Hydrolysis.)
I think the work on genetically engineered crops and novel enzymes for breaking down cellulose is more cutting-edge. That means it could make a more interesting project, but it is also much harder for a beginner to setup and perform the experiments successfully. If you can find someone working in this area to help you, these are some possible experiments you could do:
a) see whether a "normal" or genetically engineered version of a crop grows more successfully under local conditions
b) see whether a normal or genetically engineered crop produces more sugar or ethanol in an existing process
c) see which of several different enzymes produces the most sugar or ethanol from switchgrass (or some other biomass), using an existing enzymatic technique
Here's a mini-primer on the bigger-picture questions you were asking about:
1) Don't worry too much about the energy density of ethanol vs. gasoline. Yes, ethanol has less energy per gallon than gasoline, but if it can be produced sustainably at a low price, people will happily use it instead of gasoline (and it could even be cheaper per mile).
2) That gets to the two big problems with ethanol: sustainability and cost. If we make ethanol from food crops, it competes with other forms of agriculture (raising food prices), and has big environmental impacts (think of all the water, pesticides, fertilizers, etc., already used to grow food crops). Current techniques of making ethanol also use a lot of energy to breakdown and ferment the biomass, which has a big environmental impact and cost. People hope that cellulosic ethanol will help solve some of these problems -- that they can grow as much or more biomass per acre, with fewer artificial inputs, and that they can convert it to ethanol using less energy (and money) than they do now. This is why they are looking for weed-type crops that they can grow easily (which are mostly cellulose rather than sugar), and why they are looking for efficient processes to convert them. (Right now, there aren't any really good ways to convert cellulose into ethanol, and even the ones that convert starches to ethanol use a lot of energy.) So any research that suggests better ways to grow and convert cellulosic biomass into ethanol will be welcomed.
This site shows some of the mainstream view of the benefits of cellulosic ethanol:
http://genomicsgtl.energy.gov/biofuels/benefits.shtml
But you should keep in mind that there are limits even to cellulosic ethanol. There is only so much land and so much crop waste, and I don't think anyone has proposed that the U.S. can get more than about a third of its transportation fuel from ethanol. So something else may be needed too. You may find it interesting to compare alternative large-scale scenarios, e.g., how much land would be needed to power cars using ethanol, vs. synthetic fuels made from coal, vs. electric cars charged by solar panels, wind turbines or coal-fired electricity? What would be the other environmental impacts of each of these approaches? What about switching to more efficient cars, riding buses or bicycling to work?
Well, that turned into a long post, but I hope it helps!
