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Undergraduate Certificate in Renewable and Sustainable Energy

Undergraduate Certificate in Renewable and Sustainable Energy. Deadline March 1 //rasei.colorado.edu/ undergraduatecertificate. Energy news.

yael-fitzgerald
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Undergraduate Certificate in Renewable and Sustainable Energy

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  1. Undergraduate Certificate in Renewable and Sustainable Energy Deadline March 1 //rasei.colorado.edu/undergraduatecertificate

  2. Energy news Lawrence Livermore National Laboratory’s NIF laser facility delivered a burst of light with 1.9 megajoules = 1.9*106 J. How fast would a 2000 kg truck be moving to equal this? (Science 343, p. 721, 14 February 2014)

  3. answer Lawrence Livermore National Laboratory’s NIF laser facility delivered a burst of light with 1.9 megajoules = 1.9*106 J. How fast would a 2000 kg truck be moving to equal this? ½ mv2 = ½ *2000*v2 = 1.9*106 all in metric Joules v2 = 2*1.9*106/2000 = 0.0019*106= 1900 v=43.5 m/sec = (43.5 m/sec * 3600 sec/hr) / (1000 m/km) = 157 km/hr!

  4. Powerrrrrr! That 1.9 megajoules was discharged in 15 nanoseconds=15*10-9 sec. What was the power? Power = energy/time = 1.9*106 J/ 15*10-9 sec = 1.27*1014 Watts (average US power =1.3 * 1012 Watts. The energy for this burst was stored up in something like a battery for a while before the discharge.)

  5. Today New ideas in transportation- hydrogen, fuel cells, electric cars, hybrid cars Friday: Chapter 9, Air Pollution, but not CO2, sulfur or lead All power point images are only for the exclusive use of Phys3070/Envs3070 Spring term 2014

  6. 3. (10 Points) Table 8.4 of your text lists the ‘energy density’ for several ways an automobile may carry the energy needed for travel. Explain to a smart, but ill-educated, national policy maker what she should do about the future of US automobile traffic, from these numbers. 4. (10 points) Plug and chug: What are the rolling and the aerodynamic drag forces on my Subaru Legacy, with a weight of 3423 pounds, a frontal area of 25 square feet, the CD of a Ford Escort, a Cr of 0.01, at 60 mph? 5. (10 points) How much total work is done, in foot-pounds and in kWh, to drive twenty miles at that speed? Don’t do it, but make a mental outline of how you would compute the fuel consumed from these numbers.

  7. SWOT analysis S=Strength W=Weakness O=Opportunity T=Threat

  8. Electric car-8.3.1 • Run from the burning of coal or natural gas • Multiply efficiency at coal plant (30%)x efficiency of transmission (90%)x efficiency of car electric motor(80%) = 21.6% • Compare to internal combustion, e=20% • Range? • Battery weight? • Battery charging time? • Battery cycles?

  9. Example/Model 15 gallon fuel tank holds 15 gallons x 36.6 kWhr/gallon (text front cover page) =549 kWhr of energy. A 12 volt battery, charging at 10 amperes (DC), power = 12 V *10A = 120 W, holding the same energy needs 549 x 103 Watt -hr = 120 Watts x time Time =4575 hours to charge=191 days. At 100 Amps, 19 days.

  10. Costs? At $3.00/gallon, the tank of gasoline costs $45. The electricity at $0.07/kW hr costs 549 kwh*$0.07/kwh= $38.43 ‘system efficiency’ both ~20%.

  11. Nissan Leaf A sensor tells the driver 4.1 miles/ kWh=kiloWatt-hour. Some gasoline cars tell the driver mpg. How many mpg (equivalent energy) is 4.1 miles/kWh? Gasoline holds 36.6 kwh per gallon. 4.1 mi/kWh = (X miles/gallons) /36.6 kwh/gallon X= 4.1 miles/kwh * 36.6 kwh/gallons = 150 mpg (energy from the battery, not from the coal)

  12. NYT 5/29/2011

  13. Hybrid car-8.3.3 • Gasoline engine– for energy density, range • Run at constant speed to generate electricity for the battery—greater efficiency • Electric motor runs wheels • Motor=generator, collect energy when slowing or going downhill. • Battery to store the electricity. Enough for a short trip without gasoline.

  14. Direct conversion of fuel to electricity—skip the generating plant and transmission lines! The fuel cell. Electrolysis, backwards.

  15. Fuel cell efficiency=electric energy out/fuel energy in Burn hydrogen at 25 deg C  max 83%, useful 50% x motor 80% =40% Internal combustion engine Max (theory) 58 %, useful 20% Battery 90% x motor 80%=72% (21% from the coal)

  16. Hydrogen as fuel 2H2 +O2 2 H2O + energy We can make H2, from coal : C +H2OCO + H2 Or natural gas: CH4+2H2O CO2 + H2 Or water: 2H2O  2H2 + O2 (electrolysis)

  17. Energy density (Table 8.4) • Hydrogen 38,000 Watt hr/kg • Gasoline 13,000 • Battery 25 So the 549 KW-hr example above ( a 15 gallon tank of gasoline) would require a battery mass of 549,000 Watt-hr /25 Watt-hr/kg = 21,960 kg=22 tonnes !!

  18. Energy densities H2 gas LH2 methane gasoline 10.2 9553 38.5 24,500 MJ/m3 • 114 50.5 34 MJ/kg H2 gas has 1/8 density of natural gas LH2 has 1/10 density of gasoline LH2 – liquid at -253 deg C=20 deg K at atmo. pressure H2 gas tank- 10,000 psi (700 atmospheres=700 times the density of STP hydrogen)

  19. BioMagic—Science 342, 1329 (13 December 2013) Food!

  20. SWOT Electric car • Strength—short trips, efficient, CO2 production elsewhere • Weakness- heavy, no long trips, slow charge • Opportunity—battery technology • Threat-accidents

  21. Hybrid • S- combines short range and long range options • W-twice as much machinery • O- fuel cells for efficiency • T- Fragility of fuel cells

  22. Hydrogen S- moves the CO2 problem elsewhere else W-no hydrogen mines, energy density O- cheaper hydrogen, fuel cells T- pressures

  23. Biodiesel US consumes 3 million bbl diesel/day Ground beef contains 10-20% fat. If we use ALL of that fat for biodiesel, how much beef need we eat in one year? Mass of beef x 0.15 = 3 x106bbl/day*365 day/year * 42 gal/bbl * 3.4 kg/gal =1.56x1011 kg of biodiesel/year M=this/0.15=1.0x1012 kg/year=1.0x109 ton/year (we mine 1.1x109 tons of coal/year)

  24. Challenge! IF we ate that much beef (1.0* 109 tons/year), what is your daily share in pounds?

  25. Bio Beef • IF we ate that much beef 1.0 109 tons/year, what is your share? 1.0*109tons/year *1/(365 days/year)*2000 pounds/ton / 320*106 people =0.017*10 9-6 = 17 pounds of beef per person-day.

  26. Therefore? Nothing beats burning fossil petroleum for transportation. Or—does such combustion cause so many other problems that we must find substitutes ? Subsidize experiments—try things out. Accept the fact that some of these experiments may fail.

  27. Friday Feb. 28 • Air pollution: smog, ozone, carbon monoxide, particulates, NOX,……… • Origin? Mitigation? Dr. Christine Wiedinmyer of NCAR //acd.ucar.edu/~christin/ Next week– Lead, sulfur, CO2 and consequences

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