Transcript Electrical Power

Electrical Power
 The
rate at which electrical
energy is converted to another
form of energy.
 Thermal, Light, Motion…
Electrical Power
 Power
= current x voltage
P = I x V
 The units for power: watts (W)
Electrical Power
 All
appliances
have a power
rating to tell
how much
power it uses.
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Standard Voltage in the US is 120 V:
P = 2.0 A x 120 V
P = 240 W
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Electrical Energy
 The
amount of power that is used
over a given time.
 Energy
= Power x Time
Electrical Energy
 Electric
companies normally use
the kilowatt-hour to charge for
energy.
 Remember: 1 kilowatt is 1000
watts!
MN is about 12 cents/kWh
(When Taxes are Included)
[http://www.think-energy.net/_85256A170068279F_li_meter3a__file_meter3a.jpg]
May 1st
May 31st
688 kWh used
x $0.12 per kWh
= $82.56
Electrical Energy
 Example:
 How
much does it cost to run an
XBOX 360 (160 W) for 3 hours a
day for an entire month?
 30 days x 3 hours = 90 hours
Electrical Energy
Energy = 160 W x 90 h
 Energy = 14400 Wh or 14.4 kWh
 Each kWh in MN is 11 cents so…
 14.4 kWh x $0.11 = $1.58 per month

Click Here for Xcel Energy Calculators
Average % of Energy Usage in a Home
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