MAE 124/ESYS 103 Spring 2009

Additional Guidance for Paper 2.

Paper topic:  paper2.pdf
Writing Guide:  writing_guide.pdf



Frequently Asked Questions

1.  Can you tell me of any good resources for scientific papers pertinent to this paper topic, such as scientific journals that are highly regarded in the field?
This paper topic asks you to think about life cycle assessment as applied to "green" products. We'll continue to talk about this in class, but here are some starting points.

For life cycle assessment, take a look at the links in our suggested reading list. Other good links:
Check out the course-related news links for ideas for other technologies that might merit consideration. You might also look at the San Jose Mercury News' Green Energy section or the New York Times Green Inc. blog, both of which have extensive coverage of alternative energy issues. However, keep in mind that newspaper articles, while helpful as starting points, are not scholarly references, and we really want you to use scholarly references as your primary sources.

A good way to find scientific papers is by using either Google Scholar or the ISI web of science to search by key words for refereed publications pertinent to your topic. If you are on campus or are using UCSD proxy servers, you should be able to click through to the full publications that come up in your search.

Finally, we'll point you to David MacKay's book Sustainable Energy -- without the Hot Air, which provides useful quantitative assessments of energy demand. The synopsis makes a good starting point for reading.

2.  How do we use turnitin.com?
See the detailed instructions.

3.  How do I create footnotes? Are endnotes acceptable?
Footnotes and endnotes are both fine. Any consistent format is OK. The Chicago Manual of Style is one standard format, and you can find a detailed discussion of its usage for term papers at this University of Wisconsin writing center site.

You may also use citation methods commonly used for scientific papers, such as numbered references or in line references to author and year, with a full reference list at the end. A sample reference might be "[Smith and Jones, 2006]". In this case, you should be sure to identify specific page numbers where relevant ("[Smith and Jones, 2006, p. 291]"). This Long Island University site explains the American Medical Association style, and this University of Georgia site explains the American Physical Association Style.

4.  How should web pages be cited? What types of web pages are acceptable as sources?
If you use a web page as a source, then you should cite it, providing as much standard reference information as possible: author, web page title, creation date (if available), your access date, location, etc. Keep in mind that web pages vary considerably in credibility. In general, the most credible information comes from peer-reviewed scholarly publications (which could include electronic journals and electronic reprints posted to web pages---if you use a journal article or other publication that happens to be posted to the web, then please cite it the same way you would cite it if you had found it in the library, with standard information such as author, title, publication year, journal name or publisher, volume number, page numbers, etc.) Researched reports (with citations) from environmental organizations are also often fairly reliable, although they may not have gone through a peer review process. Some web pages are essentially advertising brochures for a particular product, and you should probably assume that the authors are presenting a biased view of their product's features. (Much material also appears in blogs, which can be interesting and provocative, but may not have much real research or information behind them. We don't recommend blogs as primary research sources.)

5.  How do I request an extension?
Please contact your TA (before the paper deadline). Note that if we grant an extension for the week 6 homework assignment (though we don't expect that you will need this), that will not extend to the paper deadline.

6.  How should I format my paper?
Please use the following guidelines.
  1. Upload Word, RTF, or pdf documents to turnitin.com.
  2. Include your name (First, then Last), PID, course title, TA's name, and date in upper right hand corner, single spaced.
  3. Use 1 inch margins, with 12 point font for the whole document. Double space the main text.
  4. Center your title at the top, but do not include a separate title page.
  5. Clearly label sections (abstract, introduction, etc.)
  6. Include page numbers, centered at the bottom of the pages.


7.  I am confused about the focus of the paper. If we research a life cycle assessment, then will section C of the report (Life Cycle Assessment) be a summary of the life cycle, or the actual assessment that we found copy-pasted?
For this paper you should perform a life cycle assessment yourself. That means that you will want to find as much data as you can about a carbon mitigation strategy, and use the formalism of life cycle assessment to evaluate the strategy. You should not plan to copy/paste anyone else's life cycle assessment (and although life cycle assessments have been completed for many products, it's unlikely that you'll find a life cycle assessment that does exactly what this paper asks you to do.)

8.  Should we focus most of the paper on judging the product, defining the life cycle, or making our own assessment of a product?
The assignment asks you both to complete a life cycle assessment and to evaluate the results. Life cycle assessments always should include an evaluation, and the paper instructions have some specific suggestions of issues you might consider. Sections C, D, and E should form the core of the life cycle assessment. The balance between these sections will depend on the topic you choose and the available data.

9.  I was hoping to get your feedback on a possible paper topic that I'm researching. I'm looking into doing a life cycle assessment of the California high speed rail that will (hopefully) run from San Diego to San Francisco. Would this be appropriate? If not, do you have any suggestions to direct me to a better topic?
Yes, this would be an appropriate topic, provided that your life cycle assessment specifically takes into account the environmental or sustainable aspects of the proposed rail line. To what extent would the rail reduce greenhouse gas emissions?

10.  What are possible paper topics?
As a starting point, take a look at the list of "green" products at the top of the paper assignment. Here are some other options on a potentially grander scale (and therefore perhaps less tractable for a comparatively short paper.)
  1. The wedges from the carbon mitigation exercise represent possible major environmental products that may be widely explored now or in the next few years. (You don't have to consider the entire wedge, however.)
  2. Any one of the three categories of solar technologies (water heaters, solar-thermal, photovoltaics).
  3. Micro-hydro
  4. Tidal power plants
  5. Geothermal power plants
  6. Biodiesel or other bio fuels
  7. High-speed rail versus cars
  8. Composting toilets
And of course, anything else you can thing of is great, provided it stays within the broad scope of the assignment. For whatever product you choose, think about materials, production, use lifetime requirements, disposal. Compare it to alternatives. Think about green house gas savings. Consider the feasibility in terms of cost, infrastructure, current resources.

11.  I have a question about the inventory analysis section of the LCA. I'm not really sure about how to implement this component into the assignment. I have some data and outcomes from some papers and a few calculations i want to carry out because they are not covered anywhere but nothing to really fill data collection, refinement and such. How should I go about this?
For the inventory analysis, think about what you would need to do if you were a manufacturer presenting a LCA for your product. You'd have data about the materials from which your product (CFLs in your case) were made, data about energy used for manufacturing, data about energy use during their lifetime, and data about disposal. Although the published literature on CFLs may not cover all of this, you should be able to report as much data as you can, identify areas where data are not readily available and make estimates for these (with large uncertainties).

12.  Some of the papers I'm using to get numbers don't match up (example: one paper bases results on CFL's having 8 times the lifespan while an other says 10) Although the conclusions are the same the numerical framework CO2 emissions and other components come from are different. How should I go about this, average, choose one or just mention both (but than how do I do my own calculations)?
You will want to discuss the range of published values in your paper. In your shoes, I think I'd take advantage of the range to develop some sense of the uncertainties in the calculation. If you're finding values of 8 to 10 in the published literature, then you could call that 9 +/- 1, and ask about the sensitivity of the results to this particular uncertainty in the published data. Formally, you could carry out statistical error propagation to show how the uncertainty in CFL lifetime influenced the final assessment, but since you only have a couple of values, it would be sensible simply to use the low and high numbers to obtain limits for the range of possible outcomes.

13.  I'm freaking out a little here and wondering if I should change my topic. Can you help?
We understand that this is a challenging paper topic, because much of the data that you would ideally want access to is proprietary or not easily available or not compiled in a single reference. Do the the best you can with published resources. Explain where you are forced to make assumptions. And don't panic. There are lots of good topics for this paper.

14.  Do you think an appropriate topic would be low-cost energy efficiency technology such as CFLs and using powerstrips to rid of phantom loads? My preliminary research indicates that switching to CFLs could reduce emissions by 90 billion tons of carbon, about 0.45 of a wedge.
Low-cost conservation strategies such as CFLs and power strips are a fine paper topic.

15.  LCA considers photovoltaic solar energy. Should I talk about the health impacts of the materials (such as cadmium) needed to created PVs, and in particular, should I address the health impacts for workers manufacturing PV systems? Would health issues still be an environmental impact?
Yes, do talk about health impacts of manufacturing---that's certainly one of the environmental impacts that can be considered in LCA, and I think that remains one of the lingering concerns for photovoltaics.

16.  I have been trying to find data about the carbon that is created when the product is being produced, but can't seem to find much on it. In the case of photovoltaics, the literature is full of information on toxicity of the materials required to produce the cells. Do I have to be really specific about carbon emissions created when making solar panels?
Since carbon emissions are one of the central goals of this exercise, you do need to address carbon. To determine how much carbon is created when solar cells are manufactured, you'll want to figure out how much energy is used, and translate that into carbon emissions. As always, it's possible that some of the information you want is proprietary, but I think you should be able to find a relevant estimate.

17.  Usually the abstracts have the conclusions and results summed up concisely, but if we haven't written the whole report yet, will we be marked down if the preliminary abstract is not complete?
Abstracts normally do summarize all the findings, but you can probably write a fairly complete abstract that summarizes what you know at this point and skirts around any lingering gaps in your conclusions. (Scientists and engineers routinely do this in order to submit abstracts for conference presentations several months in advance of the conference.)

18.  I am doing my paper on solar thermal for high temperatures (ie, the plants in the desert). Can I focus on just this technology, or do I need to compare this to another strategy (ie, photovoltaic, coal plants, etc.). If so, does this mean I need to do 2 LCA's? One for each technology?
A good life cycle assessment considers trade offs between multiple options, so ideally you should consider a base case solar thermal system versus some alternatives. Perhaps you'll be able to find a published paper that summarizes numbers for conventional power. Or you may just want to consider alternatives within the scope of the solar thermal facility that you are studying. Your page limit won't give you a lot of room for a full-blown LCA of two different technologies.

19.  I wanted to look at is the Energy Star Program for energy efficient appliances and lighting. Should I focus on the program as a whole, just appliances, or a single thing like compact fluorescent bulbs?
For this assignment, you're asked about a single product, and that's what you should do.

20.  I was thinking doing a LCA on meat production versus vegetables like soy. The LCA of different types of meats and different types of vegetables are different so should I just choose one type of meat and one type of vegetable and compare?
You'll make your analysis simpler if you consider one category of meat compared with one alternative, so beef versus soy, or beef versus fish, would be reasonable alternatives. A

21.  I am writing about photovoltaics vs coal as my LCA and have run into a few issues. The main one is that there is no current standard for photovoltaics, and are thus hundreds of different types with different materials and construction methods. Should I narrow my paper to consider only a specific type (e.g. thin cadmium telluride, poly crystalline si, etc) or take averages and general trends? The problem with using general trends is that different photovoltaics have different issues for disposal. If I am going to compare with coal, i need to be pretty specific on the waste to be useful. Do you have any suggestions on how to organize my data and specify my scope?
To make the paper tractable, I'd advise choosing one type of photovoltaic, that is one product, and explain very carefully in your life cycle assessment how you've set boundaries for your analysis. Try to choose a type of photovoltaic that is relatively widely used or that is likely to become relatively widely used---an analysis of a controversial or fly-by-night method for making photovoltaics might be unsatisfactory.

22.  When we are gathering data about greenhouse gas emissions, is it OK to draw some of that data from published life cycle assessments? For example, when I talk about the process of obtaining cadmium-telluride (the semiconductor) for PV solar energy, can I cite a LCA that explains the cadmium refining process? I know on your website it says we have to perform the LCA ourselves, and I am trying to do that, but I am uncertain what exactly that entails. As I look into materials such as the semiconductors and aluminium needed for framing and structural support for solar panels, and I have found some data in LCAs, and wondering if I can use it. Can you please tell me if I am on the right track?
Yes, it's possible that the best source of data will be someone else's published life cycle assessment, and that is troubling, because we've specifically asked you to do the life cycle assessment yourself. You should plan to do your own life cycle assessment, with a specific focus on a single green product, paying attention to the environmental problems that we've addressed in this class. Even if you end up closely following the reasoning of one or two published life cycle assessments, you'll want to be sure to adjust the method and interpretation to be consistent with the guidelines in this assignment. In the example you suggest, if you use published life cycle assessments for aluminum and semiconductors, you'll simply end up drawing on the published information as credible sources for data to support your solar panel life cycle assessment. Sounds like you're doing fine.

23.  I have some sources that have many authors (some have 5). When I cite them in my paper, is it okay to just use the first author listed, or can I just list the article name, instead? I'm really just trying to save words to keep my word count at a minimim. Maybe just listing last names would be the best, but is that allowed? Or should I footnote? I'm not quite sure how to do that, do I just number my biblipgraphy and reference only the number when I cite?
Please do include full author list in your bibliography. As we said for the first paper, we won't count your bibliography in your word count, since we don't want to discourage you from using a broad range of sources. When you reference the papers in your text, use just the first author's last name, with an "et al" to indicate other authors.

Thus if you had a reference for a hypothetical guide for this term paper, you might have the following listing in your alphabetical bibliography:

Gille, S., S. Taylor, R. Kulin, and B. Maurer, 2008. How to write a term paper on Life Cycle Assessment for MAE 124/ESYS 103, J. Pedagog. Methods, pp. 83-97.

In the text, if you weren't using end notes, you'd reference it as "Gille et al. (2008)" or "(Gille et al., 2008)".

Alternatively, you can use numbered end notes. By most conventions, they are numbered in the order that they are cited. So the first citation is "[1]", even if the author name is Zzwyg. In scientific literature, you can reuse the numbers. Thus you have a citation list numbered in order of first citation, although some sources may get cited repeatedly so that their numbers are reused again and again through your paper. If you do this, it will help us out if you also make a quick alphabetical bibliography.

In the humanities, usually each citation gets a new number, so references are repeated in the end note list again and again. By convention the first reference would contain detailed citation information and subsequent references could have reduced details. This strategy is fine too, but if you do this, we will require that you make a bibliography, alphabetized by author last name.

24.  I've just realized that some of my initial cost information comes from a life cycle cost analysis on rooftop gardens in Singapore. It's a fantastic, detailed article, and I'm just using it for initial costs and the extra weight a garden adds to the roof. The dollar amounts seem to be in U.S. dollars and the article was in Science Direct. Is it okay to use the statistics for my initial cost evaluation in my paper?
The article sounds great, and it's fine to use it. Science Direct might be the web access source, not the actual journal, so make sure that you identify the full publication information.

25.  Can I put graphs in the LCA section of my paper, provided that I cite my sources?
Yes, graphs are a good idea, provided they help you tell your story. As you note, you should be sure to identify the source of the graphs or the source of the data that you use to make the graphs yourself.

26.  Would you like the numbers to be summarized into tables? At this point I think I would rather just integrate the numbers into my paper. Is it okay to put numbers (from different sources) into my paper that aren't exactly the same?
It's your choice whether you present your numbers in a table or in a text. Numbers from different sources are fine, but of course you'll want to convert everything into consistent units so that your interpretation is clear.

27.  Can we copy and paste useful tables into our papers as long we cite the sources?
Yes, you may use tables (or graphics) from other sources if they are properly cited.

28.  Does the work cited section count in the maximum words total? What about the abstract or appendix? I did not realize how quickly 2000 words can be used in writing an LCA. I guess we have to be very selective on what to talk about.
The bibliography and appendices do not need to be included in your word count. You are exactly right that you will need to be selective in what you present.

29.  I am doing my paper comparing hybrid cars to gasoline cars. As of right now I have only done an assessment on hybrid cars and have compared the hybrid values with online sources for gasoline cars. I was wondering if I had to do my own assessment for the gasoline cars too.
You don't need to do your own assessment of gasoline cars, but you need to make sure that you have an apples and apples comparison of hybrid and gasoline cars, and that might mean adjusting the published numbers for gasoline cars to match your hybrid car assessment.

30.  For the hybrid car assessment, was I supposed to figure out the carbon emission from the production of all the car parts to the point where the car gets disposed?
Ideally, you should consider carbon emissions from all aspects of car part production, usage, and disposal. But exactly how you do that depends on how you choose to set the system boundaries for your life cycle assessment.

31.  I am having a little trouble picking my product. I was thinking of the "Simple Green: Naturals" line of cleaning products and specifically about the multi-surface product. I am worried about the amount of information I can find as far finding numbers like the stuff presented in class about music cds and downloading. How much data is expected in my paper?
A single product from the Simple Green line of products would be a good choice. You are correct that you'll probably find some of the relevant information is considered corporate proprietary information and it will not be available. But you should be able to get some information about chemical composition of the product. You don't have a big enough page count to go into the same detail that the EMI music industry study did, and I'm sure you can find some basic material to address the requirements of the assignment.

32.  Can recycled water use in san diego be used as a "green product" for my topic? I am pretty sure I can find data for this.
Recycled water is a possibility, though we'd definitely prefer that your second paper be really distinct from your first paper.

33.  Could I consider health be a type of environmental impact?
Yes, human health is an environmental impact. (Usually we consider this from an epidemiological (or public health) standpoint, so you could consider incidence of asthma, heavy metal toxicity, or cancer related to environmental pollutants. You could also consider changes in disease vectors associated with climate change or sanitation problems.)

34.  I'm thinking about about disposable vs. reusable/partially reusable children's diapers and I wanted to make sure that was OK (especially since I'm a guy....).
Disposable versus washable diapers is an appropriate topic (and no, buying/choosing and changing diapers are not gender specific activities.) There should be ample information on the topic. Water is an important component, at least in San Diego.