Power -- Kill-A-Watt Prep This is current events..

Two types of Power AC – stands for Alternating Current – It alternates 60 times per second going first from positive to negative, then from negative to positive.. DC – stands for Direct Current. This is primarily batteries and low current devices AC is able to be transported over long distances, DC can not. We would have to have a generator on every block if we used DC for homes and businesses

Using Electricity Service Panel to 120V outlets in your home I(current) X V(voltage) = Watts Circuit breaker

Watts, Amps and Volts Current, called Amps, is the number of electrons flowing per second. Volts is the “Potential difference”, meaning how much force is pushing the electrons along. Electrical Power, or Watts, is Current * Voltage or Amps * Volts Since a “Watt” is such a small unit, we usually group it by 1000, or use “Kilowatts”

Energy Vs Power Power is the electricity being used at any given moment. Energy is basically how much of that “Power” is used over time. Think about gasoline in a car, you don’t talk about how much gasoline you are using at any give moment, you talk about how many miles you can go on a gallon of gas. We use Kilowatt Hours (KWh) to measure how much energy is used over time.

Watts = Amps * Voltage Conversions: Amps = Watts / voltage Volts = Watts / Amps

KWh A 100 watt light bulb uses 100 Watt Hours in one hour. In ten hours, it uses 1,000 Watt Hours or 1 KWh. If you have a toaster that uses 600 watts, and you do LOTS of toast for 10 hours straight, that would use 6000 watt hours or 6 Kilowatt hours (KWh). A KWh in our region costs about 23 cents, so that 10 hour Toaster marathon cost you $1.40. do that every day for a year and you spend over $ Just for toast (A restaurant??)

Power Problems What is the Power used for a 2 amp device in a wall outlet (110 volts)? What power is used for a 20 amp device in a 220 circuit? How much energy would each use if they were on for 4 hours a day for 300 days? How much would the electricity for each cost?

How many watts do the following devices use: All use a 110 volt outlet An 18 amp Power Tool A.5 amp printer A 4.5 amp curling iron A.05 amp light bulb

How Electricity Works Need an energy source to produce electricity In the US that source is mainly Coal

How much Current is drawn by the following devices: All use a 110 volt outlet A 1100 watt Hair dryer? A 1500 watt griddle? A 2000 watt portable heater How much energy would that heater use if it is on for 15 hours a day for 120 days, and how much would it cost to use?

What is the voltage needed by the following devices: 4 amp, 440 watts? 8.2 amp, 900 watts? 10 amp, 3300 watts 16 Amps, 3520 watts?

CO 2 About 1.5 pounds of CO 2 are emitted for every Kilowatt hour of Electric usage. Every pound of CO 2 occupies roughly 8.75 Cubic feet at sea level, roughly equal to ½ of a refrigerator.

Electric sources Generator – Converts mechanical energy into electrical engergy Battery – Chemical Energy Generates Electricity

Power Station –

Watts= Current (I)X Voltage Water pressure Size of the pipe Voltage is the energy moving the electrons