Hello,
There is something I don’t get about power and energy.
If I got it right, power is expressed in Watts or Joules ans energy is in Watts.hours.
So if I buy à power supply rated at let’s say 700W. Does that mean (assuming, for the sake of the argument 100% efficiency and 100% load) it also consumes 700Wh ? And also that 700W is it’s maximum power output ?
In: 2
The supply rate is how much energy per second the device can draw from the grid. That being 700 joules per second(watts).
If you were to leave that at 700watts for 1 hour. You would have used 700 watthours, or 0.7 kwh.
Alternatively, you would have used 700joules/second x 3600 seconds = 2.56 million joules.
A kilowatthour is equal to 1000 joules/second*3600 seconds = 3.6 million joules.
It is a bit confusing that we used “kilowatthours” as a unit of energy, since watt is power(joules/second), but when you times it with a time you get just joules.
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