9781118041581

earlier in the chapter, the different energy sources vary with respect to

average cost per megawatt, carbon dioxide emissions, and environmental

and health consequences. (This last category combines diverse impacts:

environmental damage from strip mining or damming rivers, the

consequences of securely storing nuclear waste, worker and residential

safety risks, and so on.) These costs and impacts—expressed per megawatt

hour of electricity—are shown in rows 12, 13, and 14. Finally, cells H12,

H13, and H14 show the cost, carbon emissions, and environmental/health

impact associated with totalU.S. electricity production averaged across all

U.S. facilities. (Note that computing the average cost in cell H12 uses the

formula: B9*B12 C9*C12 ... G9*G12.)

a. Re-create the spreadsheet. Ignoring the carbon and environmental

impacts, what proportions of the energy sources would minimize the

nation’s average cost per megawatt hour (cell H12) while generating

3.8 billion MWh in total? Explain.

746 Chapter 17 Linear Programming

ABCDEFGHI

1

2 Options for US Electricity Generation

3

4 Coal Clean Coal Nat Gas Nuclear Hydro Renewable Total Goal

5

6 Output (MWh) 1.75 0 0.87 0.75 0.26 0.17 3.80 3.80

7 Maximum 2.6 0.5 1.9 0.75 0.44 0.25

8

9 Proportion 46.1% 0.0% 22.9% 19.7% 6.8% 4.5% 100%

10

11 Cost inc tax: $66.12

12 Cost $40 $60 $50 $115 $100 $150 $66.12

13 CO 2 1.1 0.5 0.62 0 0 0 0.65 .50

14 Environ./Health 100 50 80 65 15 15 78.89 65

15

16 Carbon Tax

17 $0 $0 $0 $0 $0 $0 $0 $0 $0

18

b. Answer the question in part (a) with the added constraint that carbon

emissions should be no greater than .5 ton per MWh of electricity

generated—that is, cell H13 must be smaller or equal to cell I13.What

roles do clean-coal and renewable energy sources play? Is it possible to

reduce carbon emissions below .35 ton per MWh? Explain.

c17LinearProgramming.qxd 9/26/11 11:05 AM Page 746