Electrical power is measured in watts. In an electrical system, power (P) is equal to the voltage multiplied by the current.
There is an old analogy about plumbing and electrical. The voltage is equivalent to the water pressure, the current is equivalent to the flow rate, and the resistance is like the pipe size.
The less watts you can use to get your desired outcome means the less power you will need to produce or pay for.
Symbols for electricty:
W = Watts
I = Current
R = Resistance
P = Power
A = Amps
What are Volts? Volts are what cause current to flow. One volt is defined as the “difference in electric potential between two points of a conducting wire when an electric current of one ampere dissipates one watt of power between those points.”
Current is measured in Amps. Current tells us the rate electrons are flowing at. Electrons have a negative charge, they move from the negative side to the positive side. Flowing electrons is Current. The force moving the electrons is Voltage. (Current is flowing electrons, the force moving those electrons are volts.) The higher the number of amps, the more electricity is flowing.
In our battery diagram below, the battery provides what is known as a potential difference in an electric circuit, or voltage. If we go back to our water analogy, the battery is like a water pump that propels water through a pipe. The pump increases the pressure in the pipe, causing the water to flow.
What are Watts? A watt is a measure of power. It measures how much energy is released per second in an electrical system. In our battery diagram, both the voltage and the current in the bulb determine how much energy is released. A light bulb will get brighter with the more you increase the watts or power.
To calculate Watts you times volts by current.
For example, a current of 2A flowing through a bulb with 12V generates 24W of power.
Water plumbing analogy and electricity
Volts (or potential) = water pressure
Amps (or amperes) = rate of flow
Resistance (or impedance) = restriction of the hose and valves
Watts = immediate quantity of water passing through the hose
Watthour = Amount of water passing through the hose in one hour
Current is flowing electrons, the force moving those electrons are volts.
There is a basic equation in electrical engineering that states how the three terms relate. It says that the current is equal to the voltage divided by the resistance or I = V/R. This is known as Ohm’s law.
The standard US outlet has 3 holes, One Neutral or negative, one positive and one ground. The larger long slot on the left, in the picture below, is the negative, the one on the right is positive and bottom is the ground. So a lot like a car battery which has a positive and negative, the power in an outlet is provided by your local electric company at 120 volts, verses a car battery which is normally 12 volts. (Remember, Volts are what causes the current to flow.)
Why are LED lamps so much more efficient?
Heat is normally bad in electrical. Heat represents lost power.
While incandescent lamps have been the standard for nearly 100 years, they were never terribly efficient at turning energy into light. The light is what people were looking to produce, but in the process a lot of that energy was turned into heat. That’s why you don’t want to change a light bulb right after you turn it off, and why easybake ovens actually do cook food. But most LED bulbs will remain relatively cool to the touch after running for hours. Those were hours that your light bulb was not generating heat, and thus not wasting your money on a product (heat) that you never wanted to produce.
Power = the rate of doing work, the amount of energy transferred per unit time. (Electrical power is measured in watts.)
Current= is flowing electrons
Volts = volts are what cause current to flow. The force moving the electrons is Voltage
Watts= A watt is a measure of power.
Amp=denotes the speed of electricity & is much like the measure of miles per hour (mph)
In the next blog post we will discuss Amp Hours.