We define electrical energy as the ability of an electrical circuit to do work. When we supply a voltage source across a conductor, current flows in a conductor for a specific time. As a result electricity is produces.
In other words, we also define Electrical Energy, the work done by the motion of electrons. It is the form of kinetic energy because it is produced due to the motion of electrons. If the movement of electrons is faster the amount of energy produced will be greater.
Let’s consider the potential difference between two points A and B.
As we know that if one Coulomb charge moves from point A to point B during time “t”. The work done will be one joule. And we can write the work done as
work done = v * (q /t)
We can write the electrical power in differential form as
p = v * (dq /dt)
If we place a conductor between these two points while the charge q passing through the conductor, it is nothing but current. There we know that
i = (dq / dt)
Therefore, we replace the I in the power equation and we get the formula.
p = v * i
Now if the current flows in a conductor for time “t” we can say the work done by the electrical charge as
e = v * i * t
where “e” is the Electrical energy
“v” is the voltage applied (potential difference) to the circuit
“i” is the value of current in amperes
“t” is the time in seconds
Unit of Electrical Energy
The unit of this energy is Joule. One joule is the multiplication of one watt and one second. Different units are in use. For example Watt-hours, Kilo Watt-hours, and Megawatt Hours.
Simply electrical energy = electrical power * time
Definition of Watt Hour
If use one-watt power for one hour. The amount of energy consumed will be One-watt hour.
Applications and examples of Electrical Energy
The application of electrical energy is worldwide and countless. There are other sources of energy like geothermal energy, solar energy, wind energy, biomass, and Hydro-power energy, etc. But electricity is most widely used.
As per 2018 reports the total amount of electrical energy used in the world was 22,315 TWH. This is because electricity can be converted into lighting , rotation, heat and more. So the main uses of electricity are lighting, cooling, heating, operation motors, computers, communication system appliances, and other machinery related operation.
Electricity uses and examples are around us every where. In our homes, factories, schools, even cars will convert to work on electricity.
Cons of Electrical energy
We discussed the different applications of electricity, Without Electricity the smooth process of the world would not be possible. But everything has its pros and Cons, it is costly, its generation has effects on the environment, and is very dangerous.
Production and generation
Electricity is generated by AC generators. These generators have large variation of power levels from small portable generators to large power plants. But all these AC generators are working with the same principle. When a conductor cuts alternating magnetic filed with relative motion this produces electricity in the conductor.
The difference between one generator and the other is the mechanical prime mover which rotates the winding. Some kind of generators use diesel engines, wind energy, steam engine, and even sea waves energy is used to produce clean and environmental friendly energy.
After generation in large power plants voltage is raised using electrical transformers, which is called step-up transformers. This is to transport power using power lines and to reduce losses.
Electrical energy safety tips
Electricity kills. This is for both expert electrical engineers and electricians as well as for non electrical workers. So its necessary to follow safety rules when working with electrical devices. Below is some tips to keep in mind.
- Only authorized persons to work with electricity.
- Make regular and periodic electrical inspection for equipment.
- Preventive maintenance program should improve safe conditions of the equipment and could prevent short circuits.
- Always isolate power and use LOTO to prevent unwanted operation specially during maintenance.
- Make sure to read manufacturer recommendations before operating any device.
- Keep electrical equipment away from water.
- Check portable cords and plugs before each use. Repair or replace any damaged parts.
- Know where panels and circuit breakers are to make electrical isolation in case of emergency.
- Never block access to panels and circuit breakers and keep them available.
- Ensure that all electrical equipment are well grounded and check this grounding regularly.