Understanding the Difference Between kJ/h and kWh in Energy Measurements

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SUMMARY

The discussion clarifies the relationship between kilojoules per hour (kJ/h) and kilowatt-hours (kWh) in energy measurements. It establishes that 1 kW is equivalent to 1 kJ/s, and when multiplied by time (3600 seconds), it results in 1 kWh, which represents the energy consumed or produced over one hour. The confusion arises from misinterpreting the division of kJ/s by time, which does not yield a valid energy unit. Understanding this distinction is crucial for accurate energy calculations.

PREREQUISITES
  • Understanding of basic energy units (kJ, kW, kWh)
  • Knowledge of power and energy relationships
  • Familiarity with time conversions (seconds to hours)
  • Basic mathematical skills for unit conversion
NEXT STEPS
  • Research the concept of energy conversion factors between different units
  • Learn about the implications of power ratings in energy consumption
  • Explore the differences between instantaneous power and cumulative energy
  • Investigate practical applications of kWh in household energy usage
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Students, engineers, and professionals in energy management, as well as anyone seeking to understand energy consumption metrics and their practical applications.

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I'm having trouble understanding some basic energy stuff. I know that kiloWatt is kJ/s, and if you divide by 3600s instead you get kWh. But wouldn't you just get kJ/h? How is that equal to kWh?
 
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If you divide kJ/s by 3600 s then you get kJ/s^2 which would represent the rate of change of power.

What you mean to do is to multiply power (kJ/s) by time to get energy (kJ). A "kilowatt hour" is the amount of energy conveyed in 1 hour = 3600 seconds when power is used or produced at a constant rate of 1 kW = 1,000 W.
 

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