Energy Calculator for Equipment (Vertical Flat Surfaces)  

by the National Mechanical Insulation Committee (NMIC)

Updated: 
01-30-2017

This calculator estimates the performance of an insulated vertical flat surface given the operating temperature, the ambient temperature, and other details about the system.

Instructions

  • Line 1. Enter the surface area of interest
  • Line 2. Enter average operating (process) temperature for the period of operation
  • Line 3. Enter average ambient temperature for the period of operation
  • Line 4. Enter average wind speed for the period of operation (if unknown, use 1 mph for indoor, 8 mph for outdoor)
  • Line 5. Select an insulation material. Note: Calculator does not screen for material temperature limitations - use caution.
  • Line 6. Enter a cost multiplier to modify the default installed costs (e.g. enter 1.10 to increase costs 10%)
  • Line 7. Enter the effective emittance of the exterior surface (see MIDG>Design Data>Table 1 for guidance)
  • Line 8. Enter the expected life of the insulation system in years
  • Line 9. Enter the number of hours per year of system operation (e.g. 8760 for full year operation)
  • Line 10. Enter the conversion efficiency of the system in percent

    Typical conversion efficiencies for various systems are:
    Fossil fuel boilers (Non-condensing)    65 - 85%
    Fossil fuel boilers (Condensing) 80 - 95%
    Electric resistance boilers 92 - 96%
    Electrically operated chillers 300 - 700%
    Absorption chillers 60 - 100%
  • Line 11. Select the fuel used
  • Line 12. Enter cost of fuel if known or use default value

Assumptions

  • One dimensional, steady state heat transfer
  • Base structure is a vertical flat steel surface
  • Thermal conductivity based on ASTM Specification Values
  • Installed costs of insulation are from industry sources and represent single layer installations
  • Installed costs include aluminum jacketing but do not include vapor retarders or vapor sealing
  • Fuel content, emissions and typical fuel costs are from U.S. Energy Information Administration
  • Emissions are in Metric Tonne per year (MT/yr)and are are assumed to be at the facility (except for electricity which are are at the power plant)

Note: NA means Not Available