What I do when I'm not knitting

...which is most of the time. I study, study, teach, grade, study, and also study. And then I get to take exams.

Just for filler, here's the first cume I took. (I have to pass 6 before I fail 11 in the first two years. I hope this won't be a problem. These are 1-hour exams offered the first Saturday (at 9am!) of every month.) I was able to answer 75% (we were given some broad categories to study in advance!), but I don't know whether my 75% was correct enough or how well you have to do to pass. Hopefully it won't be long.

"Electrochemical Aspects of: 1) Development of Renewable Energy Resources in the 21st Century; 2) Hydrogen as a Replacement for Fossil Fuels.

1. Current predictions suggest that global production of fossil fuels will reach its peak sometime in the next 50 years (some studies suggest it may have already peaked!).

a) What challenges does the peaking of fossil fuel production pose for highly developed countries (e.g., the United States)?
b) How are these challenges different for developing countries and countries with very large populations?
c) Name at least three distinctly different types of renewable energy. For each briefly comment on its availability, current cost effectiveness and how energy is produced.

2. The advantages of fuel cells in comparison to combustion engines have been known since the 1800's. However, fuel cells are only now being considered for widespread transportation applications (e.g., automobiles).
a) What is the primary advantage of fuel cells w.r.t. to (sic) the the internal combustion engine for converting chemcial fuels into usable energy?
b) Despite their inherent advantages, why has the development of fuel cells lagged behind the development of combustion engines?
c) What is a PEM fuel cell? Why was the PEM fuel cell considered to be a technological breakthrough?
d) There are three general types of H2/O2 fuel cells: acidic cells, basic cells, and solid oxide cells. What is (sic) the main advantages and disadvantage of each type of cell?

3. One possible renewable source of hydrogen is through photochemical water splitting. There are currently three basic types of photochemical systems being explored for this purpose:
- photovoltaic (PV) electrolysis
- direct semiconductor photolysis
- genetically modified photosynthetic bacteria
For two of the three photochemical systems:
a) Explain (using diagrams, reactions, etc.) how each system produces pure hydrogen.
b) Describe one important technical issue that needs to be overcome in order for the system to produce hydrogen economically.
c) Describe one key advantage and one key disadvantage of the system for producing hydrogen.

4. While hydrogen/oxygen fuel cells are the most efficient, the use of methane and methanol are bieng considered as alternatvies to hydrogen for fuel cells.
a) Why are researchers trying to develop methane and methanol fuel cells given that H2/O2 fuel cells are already highly efficient?
(Hint: what is the biggest problem associated with using hydrogen as a fuel?)
b) What is the electrochemical half-reaction that occurs in the anode compartment (where oxidation occurs) for fuel cells that utilize methanol as a fuel?
c) Compared with H2/O2 fuel cells, cells using methane or methanol are less efficient and produce less energy per cell mass (energy density). Why?
d) Unlike H2/O2 fuel cells, cells based on methane or methanol have an environmental disadvantage. What is it? Is it possible to eliminate this disadvantage?"