Question

What is the difference between kw (kilo watt) and kwh (kilo watt hour).

Answer 1

There is only one difference: the element of time.

KW is the unit of power; it means kilowatts, or 1000 watts of power.

KWH is the unit of energy; it means kilowatt-hours, or 1000 watt-hours of energy used, delivered or stored.

In a sense, KWH is about how much work there is to be done and KW is about how fast you can get the work done.

For example, if you have a big tank that you must fill with water, it will take a given amount of energy to fill it, let's say 10 KWH.
Now, if you have a 1 KW pump available it will take you 10 hours to fill the tank.
If you have a 5 KW pump instead, it will take 2 hours to do the job.