Difference Between Energy and Power

All organisms use energy to survive, grow, reproduce, or carry out any activity. It is converted or transferred to an object to create ‘change.’

Doing the simplest tasks, such as picking up a pen is required. On the other hand, power refers to the rate at which a certain amount of energy is used.

For example, power measures how fast a pen is being picked up; the faster it is picked up, the more power is used by the person applying force.

Key Takeaways

1. Energy is the ability to do work or create change, while power is the rate at which energy is transferred or used.
2. Energy is measured in joules or kilowatt-hours, while power is measured in watts or kilowatts.
3. Energy is a scalar quantity, while power is a vector quantity with both magnitude and direction.

Energy vs. Power

Energy is the ability of a body to do a task, and without energy, the body will not be able to perform any task. Energy can be changed into different forms depending on the task body is performing. Power is the measure of the rate at which the body is performing a task. Power cannot be stored.

Comparison Table

Parameters of Comparison	Energy	Power
Meaning	Energy is a measurable property that makes ‘change’ happen when transmitted or converted.	Power is the rate at which energy is used or transferred during a certain period of time.
Standard unit of measurement	The standard international unit of energy is Joules.	The standard international unit of power in Watts.
Symbols	The symbol ‘W’ is used to denote energy.	The symbol ‘P’ is used to denote power.
Calculation	Energy is calculated by multiplying power with time {Energy (W) = Power (P) × Time}.	Power is calculated by dividing energy by time {Power (P) = Energy (W) ÷ Time}
Storage	Energy can be stored.	Power can’t be stored.
Conversion	Energy can be converted from one particular form to another.	Power can’t be converted from one form to another.
Examples	Energy is required to carry out tasks such as picking up a pen, throwing a ball, climbing a ladder, etc.	Power refers to the rate the pen is picked up, the ball is thrown, the ladder is climbed, etc., concerning time.

What is Energy?

The word ‘energy’ comes from the Ancient Greek word ‘energeia,’ first appearing in the great philosopher Aristotle’s work. At that time, the term was more qualitative than quantitative.

It had a philosophical context and included broad ideas such as sadness and happiness. In physics, energy is a measurable property that can be used or converted to make ‘change’ happen.

This change could be in the form of motion, heat, and so on. All organisms store energy in them, which they take from food.

They use this energy to survive and flourish. In 1843, James Prescott Joule derived a unit for energy, Joules, now the standard international unit.

The energy used to exert a force of 1 Newton while spanning a distance of 1 meter is measured as 1 joule. Every object that has some amount of mass stores energy as well.

This is in the form of rest energy. Other common forms of energy include potential, kinetic, elastic, chemical, thermal, and radiant energy.

What is Power?

Power can be defined as the measure of how fast work is done. It is the rate at which energy is used or transferred to an object to create change.

For example, a certain amount of power is taken to exert force while pushing a door. The standard international unit to measure power in Watts.

The power taken to exert 1 joule of energy in 1 second equals 1 watt.

When more power is used, the work is done in less time, while less power means more time has been used. Their standard equation can understand the correlation of power with time.

Power is calculated by dividing energy by time {Power (P) = Energy (W) ÷ Time}. The definition and equation of power had an important use in the invention of the steam engine during the early 70s in England.

The Scottish inventor, chemist, and mechanical engineer James Watts was responsible for developing the concept of power. He did this by introducing his Watts steam engine in 1776, which was an upgrade of the previously used Newcomen steam engine.

Main Differences Between Energy and Power

1. Energy is a measurable property that can be used or transferred to make ‘change’ happen, while power is the rate at which this energy is transferred.
2. The standard international unit for measuring energy is Joules, while the standard international unit for measuring Power is Watts.
3. Energy is denoted by the symbol ‘W,’ while power is denoted by ‘P.’
4. Energy is calculated by multiplying power by time, while power is calculated by dividing energy by time.
5. When force is applied to pick up a pen, a certain amount of energy is exerted. Meanwhile, the rate at which this energy is exerted refers to power.
6. Energy can be stored while power cannot.
7. Energy can be converted while power cannot.

References

1. https://eric.ed.gov/?id=EJ349839