Enter the cross sectional area (m^2), the flow speed (m/s), specific heat (kJ/kg-k), temperature difference (K), and the density (kg/m^3) into the Waste Heat Calculator. The calculator will evaluate the Waste Heat. 

Waste Heat Formula

The following formula is used to calculate the Waste Heat. 

Qwaste = A * V * p * Cp * T


  • Qwaste is the Waste Heat (kW)
  • A is the cross sectional area (m^2) 
  • V is the flow speed (m/s) 
  • p is the density (kg/m^3) 
  • Cp is the specific heat (kJ/kg-K)
  • T is the temperature difference (K)

How to Calculate Waste Heat?

The following steps outline how to calculate the Waste Heat.

  1. First, determine the cross sectional area (m^2).
  2. Next, determine the flow speed (m/s). 
  3. Next, determine the density (kg/m^3). 
  4. Next, gather the formula from above = Qwaste = A * V * p * Cp * T.
  5. Finally, calculate the Waste Heat.
  6. After inserting the variables and calculating the result, check your answer with the calculator above. 

Example Problem:

Use the following variables as an example problem to test your knowledge.

cross sectional area (m^2) = 4

flow speed (m/s) = 30

density (kg/m^3) = 100

specific heat (kJ/kg-K) = 1.21

temperature difference (K) = 2.5

Qwaste = A * V * p * Cp * T =  ?