Difference between kilowatts and kilowatt-hours

The Kilowatt (kW) is a unit of measurement of Power; in other words, the kW is, by definition, the amount of Energy absorbed in the unit of time. One kW, equal to 1,000 Watts, identifies the unit of electrical power (W = J / s) and represents the amount of Energy (Joule) over time (seconds).

Kilowatt-hour (kWh) is the unit of measurement of electricity. In fact, the Kilowatt-hour is formed by the terms Kilowatt and hour and indicates the Energy supplied in an hour with the Power of one Kilowatt.

The two units of measurement are different; the kW measures Power while kWh is the unit of electricity consumption measurement.

A simple example: If you have an appliance in your home that has a power of 2 kW, it absorbs 2 kW per unit of time. So if you use it for one h, it will consume 3 kW x 1h = 3kWh.

Power and Energy

• The electrical Power (P) that passes through a circuit section is given by the product of the Voltage (V) and the Current (I) present in the section considered:

• P = V × I (Unit of measurement of Power is Watt, abbreviated: W)

• Electricity (W) is the product of power (P) and time (t). The unit of energy measurement is the kilowatt-hour, abbreviated to kWh.

W=P×t (kWh)

Conclusion

I want to make some clarifications on Electricity, Power, and Energy.

The Ampere (A) is the measure of the Current, while the Power is produced by the Current and is measured in Watts (W). The formula that binds them is Power (P) = Current (A) x Voltage (V), so if the Current remains unchanged and the Voltage varies, for example, 15 Amps and 20 Volts, they produce 300 Watts of Power, while if the current remains the same, but the Voltage varies.

For example, 48 Volts, the Power will be 720 Watts. The difference is big. So the Current (A) is used to size the cables, the regulators, and partly also the batteries, while the Power (W) I need to understand how much "work" the Current produces with the Voltage you choose.

All this reasoning is fine when it happens instantaneously, but it is clear that a 50 Watt light bulb kept on for an hour consumes less than the same light bulb kept on for 2 hours, even if the Power is always 50 Watts, so the method which he can do the calculations in a simple way.

Comparing consumption or production as if it had occurred in a single hour. This ratio is the Watt-hour (Wh) which is the Energy and is equal to the Power for the time (W = P * t) for which the 50 Watt bulb kept on for an hour will consume 50 Wh of Energy, and the one kept on 2 hours will consume 100 Wh.

Power and Energy

• The electrical Power (P) that passes through a circuit section is given by the product of the Voltage (V) and the Current (I) present in the section considered:

• P = V × I (Unit of measurement of Power is Watt, abbreviated: W)

• Electricity (W) is the product of power (P) and time (t). The unit of energy measurement is the kilowatt-hour, abbreviated to kWh.

W=P * t (kWh)

Dictionary

• A = current flowing at this moment is like the flow of water in a pipe that supplies the vessel.
• Wh or kWh = total Energy used, produced or accumulated; it is like the bank account.
• W = instantaneous Power produced or consumed. It is how much work we can do at the same time.