1. B. S. E. E., M. S. Space Technology
Miscellaneous Work File on Renewable Energy
Frank R. Leslie,
B. S. E. E., M. S. Space Technology
3/19/2003, Rev. 1.4
(321)
(321)

2. Overview
Renewable energy is sustainable indefinitely, unlike long-stored energy from fossil fuels that will be depleted
Renewable energy from wind, solar, and hydroelectric power emits no pollution or carbon dioxide (although the building of the components does)
Biomass combustion is also renewable, but emits CO2 and pollutants
Nuclear energy is not renewable, but sometimes is treated as though it were because of the long depletion period
Sustainable energy comes from the sun or from tidal forces of the moon and sun; usually implies not using it faster than can be replenished
Nonrenewable energies come from combustion of coal, oil, and natural gas. Their creation took millions of years, and we are using it faster than it was produced and faster than it is being created.
Renewable energies come from the sun. Collection is from natural occurrences. While the energy is free, it costs money to collect it.
Nuclear and geothermal energies aren’t renewable but are treated that way since the quantity is so large.
Revised

3. Energy Considerations for 2050
Fossil-fuel energy will deplete in the future; took millions of years to create that much fuel
US oil production peaked about 1974; world energy will peak about or so
Renewable energy will eventually become mandatory, and our lifestyles may change
Transition to renewable energy must occur well before a crisis occurs
Revised

4. Wave/Tide Ocean Current
Energy Categories
Fossil
Renewable
Conventional
Coal
Oil
Gas
Wood
Hydro
Human/Animal
Alternative
Oil Shale
Tar Sands
Wind Solar Biomass
Wave/Tide Ocean Current
Geothermal
Sustainable means using less than is renewed; if water is withdrawn from a dam faster than it is refilled, the level drops and power is lessened
Revised

5. Solar Module Tilt NP NP SP NP SP
23.5° SP
23.5° NP SP
Modules are tilted at latitude to be aimed at sun on equinoxes; at solstices, they are offset by latitude angle
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6. Battery Capacity

7. 11.4.3.1 Battery Capacity Controller Battery Inverter Load PV Module
P-C Interface
Controller
C-B Interface
Battery
B-I, Interface
Inverter 12 to 120V 1A to 10A
I-L
Load
Power In, W
208 W
=17.5 x 11.9A =208 W
148.1 W
= 133.3/ 0.9 = W
133.3 W
=120/ 0.9 = W
120 W
Voltage In, V
17.5 V
13.8 V
12 V
120 V
Current In, A
11.9 A
11.9A
=10.7A/ 0.9 =11.9 A
= 148.1/ 13.8 = 10.7 A
= W/ 12 V = 12.3 A
11.1 A
= 133.3/ 12 = 11.1 A
1 A
Capacity, A-hour
= 1181/ 10.7 = 110 hours
=12.3 A x 96 hr =1181 Ah
Power Efficiency
1 (no loss)
0.9 1
0.9 in x 0.9 out
For four days, the battery must supply 1 A to the load requiring 592 Ah capacity
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8. 12.3 Prop vs. Rotor Lift Force Rotation Torque Resultant Force
Blade Pitch
Relative Wind
Chord Line
2/3 x Wind velocity due to slowed wind
Angle of Attack
Lift Force
Drag Force
Resultant Force
Rotation Torque
Rotational Velocity
Thrust
For f
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9. Airplane Propeller Flipped Over Rotor “lift” pulls rotor around
12.3 Prop vs. Rotor
Lift
Airplane Propeller
Wind
CW WT Rotor
Wind
Driven Motion
Motion
Lift
Airplane Propeller Flipped Over
Rotor “lift” pulls rotor around
CCW WT Rotor
Weak Motion
No good for rotor
Poor Lift
Motion
Lift
An airplane propeller won’t work as a wind turbine rotor
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10. Northwestern Iowa has Wind
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12. Composite Wind and Solar Map
041214

13. Conclusion
Renewable energy offers a long-term approach to the World’s energy needs
Economics drives the selection process and short-term (first cost) thinking leads to disregard of long-term, overall cost
Increasing oil, gas, and coal prices will ensure that the transition to renewable energy will occur ― How will we choose to do it?
Revised

14. References: Books
Brower, Michael. Cool Energy. Cambridge MA: The MIT Press, , TJ807.9.U6B76, ’4’0973.
Duffie, John and William A. Beckman. Solar Engineering of Thermal Processes. NY: John Wiley & Sons, Inc., 920 pp., 1991
Gipe, Paul. Wind Energy for Home & Business. White River Junction, VT: Chelsea Green Pub. Co., , TJ820.G57, 621.4’5
Patel, Mukund R. Wind and Solar Power Systems. Boca Raton: CRC Press, 1999, 351 pp. ISBN , TK1541.P , ’2136
Sørensen, Bent. Renewable Energy, Second Edition. San Diego: Academic Press, 2000, 911 pp. ISBN
Revised

15. References: Websites, etc.
Wind Energy elist
Wind energy home powersite elist
geothermal.marin.org/ on geothermal energy
rredc.nrel.gov/wind/pubs/atlas/maps/chap2/2-01m.html PNNL wind energy map of CONUS Elist for wind energy experimenters
Site devoted to the decline of energy and effects upon population
Federal Energy Regulatory Commission
on OTEC systems
telosnet.com/wind/20th.html
solstice.crest.org/
dataweb.usbr.gov/html/powerplant_selection.html
Revised

16. Thank you! Questions? ? ? My website: my.fit.edu/~fleslie
Roberts Hall Weather:
DMES Meteorology Webpage:
080101

17. Slide stockpile follows!
Older slides follow this one. Look at these if you have interest or time. It’s difficult to decide what to leave out of the lecture to save time!