The capacity of doing work is known as energy. The unit of energy in the SI and MKS system is Joule. The energy can be in the form of kinetic, potential, electrical thermal, geo-tidal, wind, biogas, nuclear, and other forms. There are two basic classifications of energy-renewable and non-renewable energy.

**What is the SI Unit of Energy?**

The following table shows unit in the SI system.

SI Unit | Joules (J) |

The name of this international unit is kept in honor of British physicist James Prescott Joule. When we apply 1-newton force and the mass displaces by 1 meter in the direction of the applied force, then the work done is equal to 1 Joule. Thus, 1N.m is equal to 1 Joule. The joule is symbolized as J.

**What is the CGS Unit Of Energy?**

The CGS stands for centimeter-gram-second. The following table shows the unit in the CGS system.

CGS Unit | Erg |

When we apply 1 dyne force and the mass displaces by 1centimeter in the direction of applied force, then the work done is equal to 1 Dyne. Thus, 1N.m is equal to 1 Joule.

The erg is equal to 10^{-7} J.

**What is the MKS Unit Of Energy?**

The CGS stands for centimeter-gram-second. The following table shows the unit in the MKS system.

MKS Unit | Joules |

**Units Of Energy List**

Some common units of energy are as follows.

- British thermal unit (BTU)
- Horsepower
- Kilowatt-hour (kWh)
- Calorie
- Electronvolts (eV)
- Hartree (the atomic unit of energy)
- Rydberg units
- Barrel of oil

**Energy Conversion**

The energy conversion list is shown in the below table.

**Commercial Unit of Energy**

Kilowatt-hour(kWh) is the commercial unit. If an electrical load consumes 1kW power for an hour, then the kWh consumed by the load is 1kWh. One kWh is also called a unit.

1 kWh | 1 Unit |