Calculation of HVAC Energy Consumption from EnergyPlus loads

DesignBuilder calculates boiler, chiller, DHW fuel consumption from the loads calculated by EnergyPlus using the CoP data at the building level on the HVAC tab as follows:

Simple HVAC

Boiler energy = EnergyPlus heating loads / Heating system CoP

Chiller energy = EnergyPlus cooling loads / Cooling system CoP

Compact HVAC

Boiler energy = (EnergyPlus heating loads x Heating distribution loss factor) / Boiler CoP

Chiller energy = (EnergyPlus cooling loads x Cooling distribution loss factor) / Chiller CoP




Heating distribution loss factor = 1 + (Heating Distribution Loss) / 100

Cooling distribution loss factor = 1 + (Cooling Distribution Loss) / 100

DHW (Simple and Compact HVAC)

DHW energy (kWh) = DHW CoP x 1000 (kg/m3) x 4.187 (KJ/kg-K) x (EnergyPlus DHW m3 loads) x (Delivery water temperature - Mains water temperature)




DHW CoP is Heating system CoP when using '1-Central heating boiler' DHW type


Data shown in blue is HVAC model data.

Data shown in italics is read from the EnergyPlus results eso file .