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Energy use drops but energy bill same

asked 2025-03-19 03:39:47 -0500

Sfrepp
116 ●6

updated 2025-03-19 06:28:58 -0500

Aaron Boranian

14430 ●91 ●25 http://bigladdersoftware.com/

Working on a simple study model, with BSLN and PROP cases.

DistrictCooling:Facility is lower in PROP.
Zone Air System Sensible Cooling Energy is lower in PROP.
Yet, Electricity:Facility is still the same in both cases. Why?

I am unable to find why lowered cooling does not affect energy cost. I am not a seasoned EnergyPlus user. Any help is deeply appreciated.

All EnergyPlus files and results are saved here.

Thank you!

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answered 2025-03-19 20:19:22 -0500

shorowit

12700 ●224 ●9 https://www.nrel.gov/b...

You are using ZoneHVAC:IdealLoadsAirSystem objects, which are idealized HVAC systems w/ COP of 1. They do not represent realistic equipment and are accounted for in EnergyPlus as district systems (i.e., outside the building facility) that perfectly meet the thermal load. Even if you somehow accounted for the district system use in your energy costs, it would not be a meaningful result.

The only way to get meaningful energy cost impacts is to model a real HVAC system with an efficiency and fuel type.

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Asked: 2025-03-19 03:39:47 -0500

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Energy use drops but energy bill same edit