I literally have brain damage(stroke) and i know i understood this once so you dont have to dumb it down too hard. hit me
In: 16
1 watt (W) is 1 joule/second. k is kilo and means 1000, so 200kW is 200,000 joule/second.
Just multiply it with the time in seconds to get the total amount of energy.
kWh (kilowatt hours) are commonly used energy units for electricity. An hour is 3600 seconds so 1kWh = 1000joule/second * 3600 seconds =3,600,000 joule. Because the time electricity is used is often closer to hours not second it is a more convenient unit. It is important to remember that kWh is not a power or time unit it is an energy unit
This means if you change for 1 hour the energy is 200kWh, if you do that for 2 hours 400kWh.
Per minute it is 200/60 =3.3333… kWh so if you change for 5 minutes the energy is 16.7 kWh
Watt is already a rate. It measures how much energy per time you have.
Watt means joule per second.
So if you are charging at 200 kilowatt you are charging 200 kilo joule per second.
in a minute you have 60 times what you have per second: 12 mega joule.
If you charge for an hour you will have 200 kilowatt hours of energy, which due to the number of seconds in an hour works out to be 720 mega joule.
For comparison the amount of energy you gain from one food calorie is 4.184 kilojoule and the amount of energy released by one kilogram of TNT is 4.184 magejoule (yes this is not a coincidence food calories are the same thing as 1 gram of TNT equivalent energy wise).
The energy you get transferred in an hour is about as much energy as you would get from burning 16 kilograms of oil.
In a little under 6 hours you have enough energy transferred to get the equivalent of a ton of TNT. In 10 years you would have transferred enough energy to be the equivalent of the energy by LittleBoy release in Hiroshima.
200 kilowatt is a lot of power though, and much more than you would see in any household appliance. That might be like running 200 blenders or 3,000 light bulbs, or one Tesla Model 3 with the pedal to the metal.
Energy is measured in watt hours, kilowatt hours, joules, and other units. This is the amount of work that is done by a power source over a period of time. This is what your electric company bills you for. Your hair dryer might use 1.5 kilowatts, but if you use it for 40 minutes in a month, then your electric company will bill you for 1 kilowatt hour.
Now an electric hot water heater might use 200 kilowatt hours of energy in a few months time.
You got the technical answers about joules per second in other responses, but if part of your question is “so how do I conceptualize how much that is?” here are some thoughts.
I have a Tesla that holds 60kWh, and gets around 200 miles on a full charge. That means that it uses 300 Wh per mile, which means that when traveling at highway speeds, it’s consuming about 18 kW.
A car with pretty average mileage of 25 miles per gallon of gasoline gets as much distance from a gallon of gas as my Tesla does from 7.5 kWh.
So 200 kW is the power to move 11 cars at highway speeds. It’s a little less than half a gallon of gas every minute (in terms of the useful energy you’re used to getting from gas).
A Newton is a kilogram meter per second squared [kg m/s^2]. It is a measure of force, that is, if you apply one Newton of force to one kg, it will accelerate at a rate of 1 m/s every second.
A Joule is a Newton-meter [Nm]. It is a measure of work, that is, if you apply a force of 1 Newton across a distance of one meter, you have done one Joule of work.
A Watt is a Joule per second [J/s]. It is a measure of power, that is, if you do 1 Joule of work every second, then your power output is 1 Watt.
The prefix k means kilo, and indicates a multiple of 1000.
Hence 200 kW is 200 [1000 kg/m/s^2 m/s] or 200 000 [kg m^2/s^3].
Equate it to your energy bill: KWH. Its a multiplication of power and time. Means you are running 1 full kw during 1 hour.
So 1 kw during half an hour is 1/2kwh. 10 kwh during 6 minutes (1/10 of an hour) is also 1kwh.
200kWh its a measure of energy, but it is necessary to know the power and time to really understand it.
1 100W lamp lit up during an entire year is 876kwh. A 20W lamp is 172kwh over a year.
But a 10kW engine will spend that energy during 10 hours. So you really need to know what consumed that energy for how long to understand what you’re talking about.
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