The question

1. The question How can this country, the developed world, and the yet-to-be-developed world continue to enjoy both the advantages of the Industrial Revolution and a livable world? Science and technology—understanding and gadgets Social, political and economic constraints—esp. population Leadership—who makes the decisions, on what basis?

2. Pascal’s wager • If in doubt, play it safe. • The precautionary principle.

3. Tragedy of the commons • What is this? Examples?

4. Do we have enough fossil fuels to continue the industrial revolution?R/P ratios • Fracked gas. Table 2.1 / Fig. 2.2 or 2.6 • Petroleum for transportation. ditto • Global? Table 2.2, 2.5 • Coal—Table 2.7 / Fig. 2.7 • And ---who is “we”? Global trade. • Answer—yes, for at least several decades

5. Is this Hubbert’s LAW?

6. Heat engines Thermal energy (Qin)into useful work energy (W) Efficiency = W/Qin AND –energy is conserved Qin = W + Qout, Always being careful with units

7. Ecarnot= 1-Tc/Th

8. How can we extend the Industrial Revolution? • Better heat engine efficiency, the Carnot efficiency. • ecarnot=1- Tc/Th, in Kelvin degrees = 273 +deg. C • A slick idea—the heat pump. Qh = W * COP (page 80), and COP>1. Best COP = COPcarnot = Th / (Th-Tc). If Th=20 deg C=293 deg K, Tc=0 deg C=273 deg K, COPcarnot = 293/(293-273)= 14.65

10. Electrical powerWatts= Volts * Amperes Transformers Power in = power out, but change V and I. IinVin = IoutVout Step up to send at high voltage, low current, step down to lower voltages, higher current as you get nearer the house. Only works with Alternating Current = AC Circuit breakers = fuses Stop the current if something is wrong, since high current makes high heat.

11. Can ‘renewables’ enable us to continue the Industrial revolution? • Nuclear power, withits real problems and its public perceptions. • Storage of solar or wind energy The solar constant = 1365 W/m2, and what happens on the way to the solar cell, and thence to electricity Power in wind = ½ *density*area*v3, all in metric, but we can get only some fraction of the maximum, which is 59% of the power in the wind. Solar and wind installations mostly cite their CAPACITY

12. Is climate change inevitable? • The physical facts of GHG. CO2 and other gases let solar energy in, but not out. This will raise the average earth temperature until the higher temperature emits more radiant energy to sustain the balance with incoming solar radiation, by s T4.

14. Models • Given so much CO2 etc., what happens to the average earth temperature, and to regional climates? • What human actions will change that CO2?

16. IPCC

17. The ‘promise’ If CO2 can be kept below 450 ppmv, the global average temperature will increase by only 2 deg c, and we can live with that.

18. Should we mitigate climate change or prepare to adapt? Or can we outsmart climate change? • Mitigate—put out the fires, as much as we can. Is this happening? • Adapt– learn to use the Arctic, higher sea levels, extremes of weather…….. • Outsmart—DO something—CCS, for example, or ethanol. But consider the ‘emergy’ .

19. Will common sense prevail? • Leaded gasoline • SO2 • CFC’s and the ozone layer

20. Will money talk? • Can we charge users for the harm done by the CO2 they use? • Should we? • Can we charge users for other noxious gases from burning coal? Yes SO2

21. What should research and investment priorities be? • Better efficiency • Better solar? • Better batteries or other storage? • Attitudes and expectations?

22. How to deal with failed experiments? • Corn ethanol. Cellulistic ethanol. • CCS=CO2 sequestration. • Fusion power

24. What about coal?

25. Units again One mtoe = metric tonne of oil equivalent = 42 GJ = 42*109 J = ?? Btu = ?? kW-hr =?? calories = ?? Calories

27. Cooler heads can prevail!

28. Preparing for the final • Don’t study hard, study smart. Know your foundations, and where to look for details. • You will have seen everything on the final, by HW or in earlier exams. • Be very skilled with the units. • There will be fewer ‘essay’ answers, since their grading might not be consistent. • There will be about twice as many MC questions.

29. Taking the exam • Triage your priorities. • Think twice, write once. • Do a mental outline to plan. • Look for the reasons why each problem is easy. • Let the units be your friend. The numbers will follow. • Make your reasoning clear. • Look at each answer before going on—did you truly answer the question? is your result reasonable? • There will be no grading ‘double jeopardy’ in multipart problems • Take your time. • Open book. • ASK if at all unclear.

30. Homework 10 due at 0900 Monday April 28 • If the EPA issues cap and trade permits or adds a carbon tax, spewers of CO2 will have to pay $40/ ton (English short ton=2000 pounds) of CO2. • (5) How much is this in terms of dollars per ton of carbon in the CO2? This is just another way to make the statement. Burning one ton of carbon creates 44/12 tons of CO2, so $40/ton of CO2 is the same as $40/ton of CO2 * 44 tons of CO2 /12 tons of C = $147 per ton of burned carbon • (10) If our local Valmont plant got all of its power of 312 MWe from burning coal at 30% efficiency, how many tons of coal are burned each hour? The plant must generate 312 MWe/0.30 = 1040 MWt of heat. In one hour this is an energy of 1040 MW-hr = 1,040,000 kW-hr. Coal holds 7800 kW-hr of heat energy per ton of coal (text cover page). Thus the units tell us Tons of coal per hour = 1,040,000 kW-hr / 7800 kW-hr/ton of coal = 133.3 tons of coal per hour

31. (5) If that coal is 70% carbon, how many tons of CO2 would be emitted each hour? That coal holds 133.3*0.70 = 93.3 tons of carbon burned each hour, and this gives93.3 tons * 44/12 = 342 tons of CO2 each hour. • (5) What would the EPA charge for emitting that much CO2? 342 tons * $40/ton = $13, 680 per hour. (or- 93.3 tons of carbon*$146.67 per ton of carbon =$13,684) • (5) Final part—How much would you the customer have to pay per kW-hr for that CO2 from coal? The plant sold 312 MW-hr = 312,000 kW-hr during that hour. The cost is then =$13,680/312,000 kW-hr = $0.0438 / kW-hr or 4.38 cents per kW-hr added to your bill. I currently pay about 5 cents per kW-hr, before taxes and fees.

32. (5) Why would it be cheaper for you if gas, not coal, were burned? You need not be quantitative. Burning natural gas, mostly methane, CH4+2O2CO2 + 2 H2O, gives more heat per molecule or ton of CO2 than does carbon. You can have the same number of kW-hr for less CO2 and less tax. • (10) US electricity generation from coal now emits 2600 million tons of CO2 per year. How much would the EPA collect each year from that $40/ton? Now—suggest something useful and relevant to climate change for that money. 2600*106tons * $40/ton = $1.04 *1011 = $104 Billion !!!!!

33. (10) What problem has the Montreal Protocol ( NOT the Convention)fixed? • This happened easily and quickly. Why? Atmospheric research showed that an ozone hole was growing in the upper atmosphere, initially around Antarctica. This loss of ozone (O3) was letting harsh ultraviolet light from the sun to reach the surface, causing sunburns, skin cancers, and crop losses. Chemical research showed that compounds known as CFC’s were causing very efficient chemical reactions that depleted that ozone. Many nations of the world decided and promised to stop producing those CFC compounds in a conference in Montreal, and did. Global CFC production dropped, and the ozone hole is healing. This was easy because: 1. Cause and effect were known quickly and reliably. 2. Other chemical products could do the same jobs as the CFC’s. 3. CFC’s were not vital components of national and global needs. Context—is the CO2 problem parallel?

34. Friday • Enthusiastic class presentations. Then- • Office hours Wednesday 9-5 • FINAL Wednesday evening, 7:30-10.