1. Read through the Executive Summary of the UKERC report on the Rebound Effect. Briefly describe the difference between the "direct" rebound effect and the "indirect" rebound effect.
2. Critique the figures and the analysis on pages 11-13 of ExxonMobil's "Outlook for Energy - A View to 2030".  Briefly address what is being assumed about how energy efficiency gains will affect energy demand in the future.
3. Open the Microsoft Excel workbook Interactive model. This has been set up so that the numbers in the white cells can be changed and the charts will automatically be updated.  (You may have to zoom in or out to see the full image clearly, depending on your screen resolution.)
   1. On the "E vs. Y" tab, experiment by changing the entries in the white cells.  Try to see how each of these changes the chart beside it.  
   2. After you have played with it for a while, you will have forgotten where you started.  .
   3. After you reset to base values, increase the energy price from 0.05 to 0.10.

                       i. What happens to the values of E and Y? 

                       ii. What does this imply about global economic activity if OPEC were to increase oil prices? 

                       iii. What does this imply about energy demand if a global carbon tax were to be imposed? 

                       iv. About global economic activity?

                    v. What happens to the E/Yratio? What does this say about how energy price affects the ability of energy to create output?

1. Still on the "E vs. Y" tab, reset to base values.  Then,
   1. Increase capital from 1.00 to 1.50. 

                   i.    What happens to energy use? 

                   ii.    To output? 

                   iii.    Why? 

                   iv.    What are the new values of energy and output?

1. 1. Reset to base values and then do the same with labour.

                   i.    What happens to energy use? 

                   ii.    To output? 

                   iii.    Why? 

                   iv.    What are the new values of energy and output?

1. 1. Reset to base values and change the Ease of Substitution (technically, the elasticity of substitution between energy and the other inputs) to 1.5.  Now increase the energy price from 0.05 to 0.10. 

                     i. How do the values of energy and output compare to those you saw in question 3. c.?

                     ii. How does the E/Y ratio compare?

                    iii.    What does this tell you about the role of ease of substitution in determining the economy's response to an energy price increase?

                    iv.    What does this tell you about the relative size of a carbon tax needed to achieve a given level of energy use for an economy (or economic sector) that exhibits greater ease of substitution than another economy?

1. Now go to the "E vs. Y (with efficiency)" tab.  Reset to base values.
   1. Increase the Energy Efficiency Gain from 0% to 100%. (This doubles energy efficiency-half the physical energy is now needed to produce the same "effective" energy.)

                            i.    What happens to the value of E?

                            ii.    What happens to the value of Y?

                            iii.    What happens to the E/Y ratio?

                            iv.    Why doesn't the doubling of energy efficiency result in a halving of energy use?

                            v.    Why does increasing energy efficiency increase output?

1. Now go to the "Growth" tab.  Reset to base values.
   1. First note that the long run growth rates are all approaching the growth rate of labour, 3%.  Increase the savings rate from 5% to 10%.

                            i.    Does the long-term growth rate of the economy change?

                            ii.    What happens to the overall levels of economic output?

1.  
   1. Reset to base values.  Increase the energy price from 0.20 to 0.40.

                             i.    Does the long-term growth rate of the economy change?

                             ii.    What happens to the overall levels of economic output?

1.  
   1. Reset to base values.  Increase the "Energy Price change in year 30" from 0.00 to 0.20.

                             i.    Does the long-term growth rate of the economy change?

                            ii.    What does the one-time increase in energy price do to energy use?  Does the long-term growth rate of the energy use change?

                            iii.    What happens to the overall levels of economic output?

                            iv.    What does this tell you about the ability of a one-time energy price increase to restrain energy demand? 

1. Now go to the "Growth (with efficiency)" tab.  Reset to base values.
   1. Change the Annual Energy Efficiency Gain from 0% to 5%. (Notice that, with Ease of Substitution set, as it is, to 0.5, the heavy dashed red line on the "Log Growth" chart is the energy demand trajectory you saw without the energy efficiency gain-it is the reference base energy demand line you should be looking at. The solid red line is the active energy demand line.)

                            i.   What happens to the growth rate of energy demand?

                            ii.  What happens to the growth rate of output?

                            iii. What happens to the E/Y ratio?

1.  
   1. Leaving everything else as you now have it, increase the Ease of Substitution from 0.5 to 1.5.

                           i. What happens to the growth rate of energy demand?

                           ii. What happens to the growth rate of output?

                           iii. What happens to the E/Y ratio?

                         iv. What does this tell you about the relevance of ease of substitution to the effect of continual energy efficiency gains on energy growth?