Update: I am actually searching for really simple, intuitive ways to explain it. I have a background in engineering, but am struggling to explain why we “pay for kwh”, and not kw (on our electricity bill) to someone who doesn’t. I have tried in many ways but maybe I’m not giving the right examples or making the right comparisons. I am really searchig for a way to ELI5.
In: 24
Think of it as gas mileage on your car. The trip computer will tell you at any one time how much fuel you’re currently using but to know how much you’ve used in total you need to multiply that by the distance you’ve travelled.
A kW rating tells you how much energy a device uses at any one moment, but to know how much energy you’ve used in total you need to multiply that by how long you’ve used it for.
When you start pushing a cart, you keep applying an amount of power to it, measured in KW, so that it keeps moving.
All the cart pushing while you do your shopping is measured in KWh: KW per hour, e.g. the total amount of energy used by you during that shopping cycle.
One is a rate of power expenditure, and one is a quantity of energy spent (or stored.. batteries also have a Wh value associated with them, or more commonly mAh which can be converted to Wh using the voltage of the battery (milliAmp hours)). Power (Standard unit of Watts) is defined as energy per time (Joules/Second)
kW is the *rate* of power consumed when you use a device.
If a device requires 1 kW and you use it for 1 hour, you have used a *quantity* of 1 kWh.
This is how energy companies measure your power usage, by how many kWh you use per month. Different amounts put you in different tiers, which give you different rates.
Edit: added the words “spent (or stored)” for clarity, changed a few things for accuracy
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