How do I convert kW to kWh for my project involving a heat exchanger?

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In summary, the conversation discusses the conversion between watts and kilowatt-hours for a 60W device, and how it relates to the use of BTU as a unit of measurement in the United States. The conversion factor for kW to kWh is 1 kW = 3412 BTU/hr, and 1 Joule is equal to a Wattsecond.
  • #1
FQVBSina
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Say I have a 60W device.

I know running for one hour it uses 60 W x 3600 s = 216 kJ of energy.

Does that mean it uses 216 kWh of energy?

Or does kWh means 60 W x 1 hour = 60 kWh?

I am confused because the units in 60 kWh is not in their simplified terms.

More specifically, this pertains to a project that I am working on.
From experimental values, I found that with X kg/s of water flowing through the heat exchanger and some temperature increase, I can find the power of the heat exchanger in kW.
I would like to provide the values in BTU since that is just what people still use in the States.
I realized BTU is an energy unit, not power, and 1 kWh = 3412 BTU.
So I need to convert kW to kWh.
 
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  • #2
FQVBSina said:
Or does kWh means 60 W x 1 hour = 60 kWh?

you have a k in there that you shouldn't

60 W x 1 hour = 60 Wh

FQVBSina said:
So I need to convert kW to kWh.

so going from what I wrote above

a 1kW heater running for 1 hour = 1kWh
 
  • #3
davenn said:
you have a k in there that you shouldn't

60 W x 1 hour = 60 Wh
so going from what I wrote above

a 1kW heater running for 1 hour = 1kWh
Alright, thanks! I thought kWh is basically kJ. I guess kWh needs to convert by a factor of 3600 before it becomes kJ then.
 
  • #4
FQVBSina said:
More specifically, this pertains to a project that I am working on.
From experimental values, I found that with X kg/s of water flowing through the heat exchanger and some temperature increase, I can find the power of the heat exchanger in kW.

Yes that's possible/correct.

I would like to provide the values in BTU since that is just what people still use in the States.

I believe they actually use BTU/h (BTU per hour) but the "h" is sometimes omitted (bad practice).

So you just need to use..

1 kW = 3412 BTU/hr
 
  • #5
FQVBSina said:
Alright, thanks! I thought kWh is basically kJ. I guess kWh needs to convert by a factor of 3600 before it becomes kJ then.
One thing worth remembering: a Joule is a Wattsecond.
So 3600 J = 3600 W s = 1 W h = 0.001 kW h .
 

Related to How do I convert kW to kWh for my project involving a heat exchanger?

1. What is the difference between KWh and kW times Time?

KWh (kilowatt-hour) is a unit of energy, while kW (kilowatt) times Time refers to power. In other words, KWh measures the amount of energy used over a period of time, while kW times Time measures the rate at which energy is used.

2. How is KWh calculated?

To calculate KWh, you need to know the power in kilowatts and the time in hours. The formula is KWh = kW x Time (in hours). For example, if a device has a power of 2 kW and is used for 5 hours, the KWh used would be 2 kW x 5 hours = 10 KWh.

3. Can KWh and kW times Time be used interchangeably?

No, KWh and kW times Time cannot be used interchangeably. They measure different quantities and cannot be converted into each other.

4. Why is KWh a commonly used unit for energy measurement?

KWh is a commonly used unit for energy measurement because it takes into account both the power and the time aspect. It is also easily understood by consumers and is the standard unit for measuring household electricity usage.

5. How can I use KWh and kW times Time to manage my energy usage?

By monitoring your KWh usage over time, you can identify patterns and make adjustments to reduce your energy consumption. Similarly, tracking your kW times Time can help you identify peak usage times and find ways to reduce your power consumption during those periods.

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