Using Honeybee THERM to Calculate Psi-Values

@chris that is fantastic, thanks! - I’ll take a look at the updated component structure and see how I can revise the Psi-Calculator portion to work more effectively / automatically and will post an update.

@EmmanuelR for Honeybee / Energy+, ‘Thermal Bridges’ are taken into account in two ways:

  1. In the U-Factor any ‘repeating’ thermal bridges from studs or similar items are taken into account in the determination of that U-Factor value (w/m2-k or Btu/hr-ft2-F)

  2. For what are considered ‘construction’ or ‘geometric’ thermal bridges (with Psi-Values, in w/mk or Btu/hr-ft-F), these are not directly taken into account in Energy+ I don’t believe, but you can use a workaround to add the extra heat-loss from these effects into an Energy+ model through the use of an ‘OtherEquipment’ object so that the effect on the zone thermal balance is influenced by this extra heat loss and the energy/load calculations will register this. See here for more info on this method: https://unmethours.com/question/8758/clarification-of-energyplus-otherequipment-impact-on-hvac-loads/

Another method is the way DesignBuilder does it, but as they state in their reference guide, since E+ doesn’t include Thermal Bridge objects by default, some funny business (creating a fictitious wall with the equivalent thermal conductivity) is needed in oder to take these thermal bridge effects into account:

Anyway, I’ll try and add an implementation of folding these Psi-Values into an E+ mode to a more complete example file once I have the Psi-Value calculator working better and I’ll add that here for your thoughts.

thanks,
-Ed

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