Electrical Engineers (Alfred Culbreth)design computers, electronic equipment, .... do not take the superior electronics courses that an Electrical Engineering would take.

1. Why Take Electrical Engineering?
Like computer literacy, electrical literacy is very
important to engineering and everyday life
• So many factors are operated or managed by power
• It is used to connect by movie, wi-fi, phone or data
• So many actual phenomena are calculated using
transducers (devices that turn between an actual
actual phenomena and an electrical volts, current or
resistance that is easily calculated and documented
for analysis)

2. Some Transducers
• Light bulbs, buzzers, alerting devices
• Speed indicators
• Strain gauges
• pH sensors
• Temperature or light sensors
• Flow sensors
• Electric motors
• Sound or movement sensors

3. Problem Solving
EE 188 also develops problem-
solving and thinking skills –
circuit problems must be
solved using reasoning and
thought, not just by plugging
into formulas

4. Energy Crisis
• People are using up cheap, nonrenewable energy sources
such as oil and coal
• Use of oil and coal produces excess carbon dioxide and
global climate change
• 70% of oil is imported
– Dependent on global pricing variations
– Impacts our security

5. Renewable Alternatives
• Nuclear energy
– Atmospherically clean
– Dangerous
– Nuclear waste problems
• Wind energy
– Clean but unsightly
– Not dependable – needs storage capability
– Not abundant where needed most

6. Renewable Alternatives
• Solar
– More expensive
– Not dependable – needs storage capability
• Geothermal and Hydroelectric
– Environmentally sensitive
– Limited resources

7. Transportation Alternatives
• Plug-in electric gasoline hybrids
• Biofueled vehicles
• Natural gas-powered vehicles
• Hydrogen-powered vehicles
• Fuel cell-powered vehicles

8. Plug-In Electric Hybrids
• Potential Barriers?

9. Where Does Electricity Come From?
• We buy it from power plants
• We can generate it ourselves
– Diesel or gasoline generators
– Generated in our car
– Generated by home solar or wind power
• We can get it from batteries
• Sometimes we get it when we don’t want it
– Lightning
– Static

10. What is the main fuel used to generate
electricity in the US?
•  Natural Gas
•  Oil
•  Hydroelectric
•  Nuclear
•  Coal
•  Wind, Solar, Biomass and Geothermal
Put a one by the fuel
most used,
a 2 by the next most
used, etc.

11. Fuels Used to Generate Electricity
• #1 Coal is used to generate 49% of the electricity in the U.S.

12. Fuels Used to Generate Electricity
• #2 Natural gas is used to generate 20% of
the electricity in the U.S.
http://www.power-technology.com/projects/bethlehem/index.html#bethlehem2

13. Fuels Used to Generate Electricity
• #3 Nuclear is used to generate 19.4% of the
electricity in the U.S.
http://www.srpnet.com/about/stations/paloverde.aspx

14. Fuels Used to Generate Electricity
• #4 Hydroelectric is used to generate 7% of
the electricity in the U.S.
http://www.desertusa.com/gc/gcd/du_glencandamtour.html

15. Fuels Used to Generate Electricity
#5 Other Renewables account for 2.4%
•Wind
•Solar
•Biomass
•Geothermal

16. Wind Power

17. Solar Photovoltaics
http://www.aps.com/my_community/Solar/Solar_22.html

18. Solar Parabolic Trough
A trough can focus the sun at 30 to 100 times its normal intensity
to heat liquid in the receiver pipe to over 400 degrees Celsius.

19. Solar Dish and Engine
A solar dish concentrates the sun at a factor of 2000 achieving
temperatures of 750 C to run an engine which turns a generator.

20. Fuels Used to Generate Electricity
• #6 Petroleum is used to generate 1.6% of
the electricity in the U.S.
http://www.power-technology.com/projects/riyadh/index.html#riyadh1

21. Fuel Usage Pie Chart (2006)

22. Energy Usage

23. Electricity Cost Chart (2006)

24. How does Electricity Get to Us?
• Wires connect the power plants to the users via the power grid.
• Long distances are covered by wires carrying hundreds of thousands
of volts
– Same power delivered by half the current and twice the voltage
– Saves money on wire (typically 40mm in diameter)
– Saves money on losses due to resistance in the wire

25. Power Grid

26. Industrial Power
• Industrial plants use three
phase power (480v) to
run most large machinery
• They run small machines,
lights, computers on
single phase power
(120/240v)

27. Residential and Commercial
• Residential and commercial customers use single phase
power – 120 volts for most uses or 240 volts for high
power appliances
• Transformers are used to
reduce the high voltages
on the power lines to the
lower voltages needed

28. AC and DC Power
• Most power generated is Alternating Current (AC)
power where the current and voltage varies
sinusoidally with time
• Direct Current (DC) power doesn’t vary with time
• Most consumer products use both AC and DC
• http://www.pbs.org/wgbh/amex/edison/sfeature/acdc
.html

29. DC Power
• DC power is used to power electronics
• DC power is easier to store (batteries)
• DC power is used in mobile applications
• DC power is useful when off the power grid
• Inverters convert DC to AC

30. AC Power
• AC power is easier to distribute
– Higher voltage and smaller current yields same power
distributed
– Transformers make it easy to change voltage levels so
smaller wire can used
• AC is used for most machinery, lights and appliances
• Power supplies convert AC to DC

31. Study of Circuits at NAU
• EE 188 – DC circuits and AC circuits when at steady state
• EE 280 – Transients, frequency response & both digital
and analog electronic circuits
• EE 380 – Linear and nonlinear electronic circuits, device
models and simulation
• EE 480 – Advanced Electronics
• EE 482 – Intro. to VLSI electronics design