Capstone Project on Earth Science

Here are the steps for completing the assignment:

Step 1 Instructions: Use this model (modified from our energy+emissions+carbon+climate model of Module 8) to find an emissions history that keeps the temperature below 3.0°C — you may keep it as low as you want, this is the upper limit (you may find that the economics are better if you keep the temperature lower). You’ll end up with a graph showing the global temperature change and the carbon emissions. The video below will show you how to do this. Please watch the video before doing anything with the model or answering the questions below.

Step 1 Deliverables NOTE: Skip these deliverables until you've cycled through Steps 1-6 and found your ideal scenario. Then produce the following: A copy (screen shot) of the graph showing the carbon emissions and the global temperature change (page 1 of the graph pad). This will get pasted into your summary poster. A brief statement demonstrating that this emissions history leaves us with enough fossil fuels left to last another 100 years. This too will be included in your summary poster, positioned next to the graph described above. How do you do this? Take the ending amount of carbon in the Fossil Fuel reservoir (this will be in Gt C) and divide it by the ending emissions rate (this will be in Gt C per year) — the result will be in years, and is the time past 2200 when we would run out of fossil fuels.

Step 2 Instructions Next, figure out how much energy we can get from that much carbon. To do this, we need to know how many EJ of energy you can get from 1 Gt of emitted C. Recall from the Module 8 activity that we looked at the figures for emissions intensities — grams of CO2 per MJ of energy. You can convert this to g C/MJ by multiplying by (12/44) and then convert to Gt C/EJ so we have the proper scale of units. If you just take the inverse of this, you have how many EJ of energy you can get by burning enough fossil fuel to get 1 Gt C in the form of emissions. For instance, if we take the current mix of fossil fuels in our energy supply and their emissions intensities, we find an average intensity of 77 g CO2/MJ. Take the fractions of fossil fuels we currently use (.33 for coal. .41 for oil, and .26 for natural gas) and multiply each of them by the carbon intensities of these fuels (103.7 for coal, 65.7 for oil, and 62.2 for natural gas), then add them up and you get about 77 g CO2/MJ — this is the amount of CO2 emitted per megajoule of energy created. This number is 21 g C/MJ (remember that a carbon atom ways less than a CO2 molecule). Then multiply by 1012 to jump from MJ to EJ, and we have 21 x 1012 or 21e12 g C/EJ, which is the same as 0.021 Gt C/EJ. Then we just flip this upside down (1/.021) to get 47.6 EJ/Gt C — this could be called the energy intensity of fossil fuels. Then, you can plug that value into the model (FF energy intensity) to calculate the energy we would get from your emissions history. FF energy intensity could be as high as 59 for 100% natural gas or as low as 35 for 100% coal — whatever number you use, you should explain how you got it. The video below will show you how to do this using the controls of the model. So, choose a value for FF energy intensity and enter this into the model. These calculations are a bit tricky, but there is an Excel file on Canvas called Step 2 Calculations in the Capstone Module that will make this easier. (The file is attached).

Step 2 Deliverable: NOTE: Skip this deliverable until you've cycled through Steps 1-6 and found your ideal scenario. Then produce the following: A brief statement saying what value you used for FF energy intensity, and how you chose that value — what does it represent in terms of a mix of coal, gas, and oil? This statement will be included in your summary poster, located near the graph showing the energy obtained from fossil fuels.

Step 3 Instructions Next, get the model to calculate how much energy we would need in total. This is easy — you’ve done it before. All you have to do is choose the global population limit and the history of per capita energy demand and the model combines these. You may choose whatever population limit you like. You may also change the per capita energy demand from the default, but it will cost you money, and you’ll have to keep track of that money (the model will keep track of it for you). The model does this by first calculating the total energy demand without any conservation, using the default graph of per capita energy demand and the population — then we subtract from that the reduced energy demand to give the amount of energy conserved. Next, the model takes this energy conserved and multiplies it by the unit cost of conserved energy, which is 0.5e9$/EJ (McKinsey, 2010). Compare this to the price of making energy from different sources in the table shown in Step 4, and you’ll see that conservation is a great deal. There is an upper limit here of 40% reduction from the reference curve, according to estimates from McKinsey (2010), so you can't push this too far. In fact, if you try to conserve an unrealistic amount, the model will override you and keep the actual per capita energy to within the 40% limit. Once you’ve got the total energy demand, the model subtracts the energy production from fossil fuels to get the energy that has to be supplied by renewables (non-fossil fuel sources). The video below will take you through the steps involved with this part of the project. Step 3 Deliverables: NOTE: Skip these deliverables until you've cycled through Steps 1-6 and found your ideal scenario. Then produce the following: A graph showing the reference global energy demand and actual global energy demand and the energy conserved (page 12 of graph pad). A graph showing the global energy demand, the carbon based energy, and the renewable energy (page 2 of graph pad). Both of these graphs should appear in your summary poster. A brief statement of what you chose for a population limit, and what kinds of challenges (if any) you think might be involved in achieving this population limit. This should be positioned next to the graph above.

Step 4 Now we move on to the costs of producing the energy. The following data, mostly from Delucchi and Jacobson (2011), can help us calculate these costs: (the table and the instructions will be provided) Step 4 Deliverables NOTE: Skip these deliverables until you've cycled through Steps 1-6 and found your ideal scenario. Then produce the following: A brief statement of what you came up with for a unit cost of renewable energy, including what percentages of the different sources you used to come up with this number. A graph showing your total energy costs, the renewable energy costs, and the carbon energy costs (page 3 of graph pad). This graph and the statement above will be included in your summary poster. Step 5 The next thing to do is to add up all of the costs related to your plan. The model will calculate the costs due to climate damages using the scheme from the modified DICE model (module 10 summative assessment) to do this, with a damage coefficient and a damage exponent. To get the total costs, we assume an economic growth rate (percent growth of gross economic output per year). It begins at $56 trillion, following the DICE model we worked with earlier, it grows at about constant annual growth rate for this time period. You can choose a growth rate between of 1-2% (in the model, this is a fraction: 0.01 - 0.02) and it will remain constant throughout the model run. The model then adds these climate damage costs to the total energy costs (renewables, plus switch, plus carbon-based energy) and the conservation costs to get the overall total costs. The video below shows how this step works.

Step 5 Deliverable NOTE: Skip this deliverable until you've cycled through Steps 1-6 and found your ideal scenario. Then produce the following: A graph showing the various costs (page 5 of the graph pad) -- the units here are all in trillions of dollars. This graph, along with some commentary will appear in your summary poster. The comments could draw the reader's attention to important things in the graph. Step 6 So far, you have gone through the process of designing a pathway or roadmap for the future and calculating the economic consequences of the set of assumptions/decisions that went into the roadmap. Now, the idea is to fiddle around with it to see if you can lower the costs, and remember that the best thing to compare here is the sum of the total costs per capita, which is plotted on page 13 of the graph pad. Your best model is the one that generates the lowest value for this parameter. In other words, you return to the earlier steps in this process, make a change, and then compare the costs with your previous version. As you do this, you will learn what kinds of changes lead to lower costs and you will eventually find the best roadmap (and remember that you also have to be able to justify it).

Step 6 Deliverable After this step, you should have calculated your best roadmap. Include a copy of the graph on page 13 of the graph pad. This should show the plots from several different versions and should highlight the preferred version. There should be a brief statement summarizing what parts of the model you changed to make the different versions.

Step 7 Step 7: Develop Project Deliverable Once you’ve found your optimum roadmap, put it all together, into a kind of poster display — a large graphic with explanatory text that lays out your roadmap for the future. In this document, you’ll take screen shots of some of the model results, and add arrows and text that illustrate what choices you’ve made and explain your justification for choosing different values and scenarios. A very rough version is shown below. An easy way to do this is to use PowerPoint, where you can load, resize, position the screenshots and then add arrows, text, etc. as needed. You can scrunch things down (or, in PowerPoint, you can specify the page size and make it very large) onto just one slide and it should all be readable when you zoom in. You could do this in other programs too, such as Keynote or Adobe Illustrator, but whichever program you choose, make sure it can save as a PDF file that you will then submit in the Capstone Dropbox on Canvas.