Watts and Kilowatts
We measure power in watts or kilowatts (1000 watts). It’s calculated by multiplying voltage times the current.
For example, a home with a 240v power supply and 100 amp service generates 24000 watts or 24 kilowatts.
A 1200 watt hair dryer using a 120v receptacle (outlet) would result in a 10 amp current flow.
I = 1200 / 120
10 = 1200 / 120
1000 watts = 1 kilowatt
If you use 1 kw for one hour, you consume one kilowatt-hour (kWh). If each kWh costs 10 cents and we use 500 kWh in a month, our electrical bill for that mouth is about $50.00
Wire Size (Gauge)
We use wires to move electricity around the house because they’re good conductors. The amount of amps that a wire can safely carry is determined largely by it’s diameter. A larger wire can handle more current, typically household circuits are designed to carry 15 amps over 14-gauge copper wire.
Resistance is measured in ohms. We use resistance to control electrical flow. Things that slow down, or prevent electricity from flowing to some place to some where are called resistors or insulators.
Electrical conductors have a relatively low resistance rating, and are useful for moving electricity to one place, to another. Most metals like copper and aluminium are good conductors. Gold and platinum are excellent conductors.
Water is a very good conductor, which is why electricity and water is not a good mix. Which also makes the human body an excellent conductor.
When we want to stop the flow of electricity, or keep it contained. We use things called insulators like air, glass, wood, rubber, and most plastics are good insulators.
Electricity moves because there is a pressure called volts, and those volts are being applied to some sort of circuit. Most utilities provide 240 volts to homes, generally with two 120 volt conductors.
Electric current is measured in amps. The more current, the more pressure (volts) and there is also a resistance to flow (ohms). The larger the flow, the more pressure. The more resistance, less pressure.
Controlling the Flow
Two dangerous things can happen with the flow of electricity:
- Too much amps will cause overheating and possibly a fire.
- Electricity may flow where it is not supposed to.
The Basics of Electricity
Electricity provides us with heat, light and power.
Where does it come from?
The utilities provide the general public with electricity, they generate it with water, burning fossil fuels, or from nuclear reactors. As, we move forward, we are seeing the requirement for more environmentally responsible way to generate electricity.
Electricity is sent from the power generation plants to grids across cities. Electricity can be alternating current (AC) or direct current (DC). In North America, we mostly use AC to power our home appliances.
Common Electrical Terms
This is where the math starts:
- V = Voltage (Volts)
- I = Current (Amps)
- R = Resistance (Ohms)
- P = Power (Watts)
You can use these in the following formulas:
Welcome to the Homeowner’s Newsletter! Each month, you’ll find plenty of useful information for keeping your house in great condition so that you can enjoy it for years to come. Preserve your investment—and keep your family safe and healthy—by maintaining your home using the following tips.
This is a short video with some tips for families moving into their new homes!
Inspecting a home in the rain, is the best time to inspect.