Unusual High cooling loads


I am modeling a room to find out the best dimensions of the window in south elevation,

Principally, in a specific WWR (window to wall ratio), There must be a balance between thermal energy and electric light, but in all conditions, the cooling load is much higher than heating and electric energy, I tested the algorithm for winter and again the cooling was higher than heating! I changed the materials but it was ineffective.

What’s the problem? Did I make mistake somewhere in writing the algorithm?



4-1.gh (558 KB)


Its possible for a space to be in a cooling mode during the winter. E+ balances the following loads:

-solar heat gain

-heat transfer through the glass

-heat transfer through all other facades

-internal program loads (people, plug loads, electric lighting, etc.)


The heat transfer through the glass/faced and infiltration will be positive or negative depending on the exterior condition, but the internal loads and solar gain will always be positive. If the internal loads and solar loads are greater than the façade heat transfer and infiltration loss, you will need to cool the space.

I recommend reviewing each of the loads listed above, particularly the internal loads settings. It is likely that one of these is too high, resulting in cooling all year.

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Leland said it all. I want only to add one comment.

There must be a balance between thermal energy and electric light

The energy for electric light in EnergyPlus (at least the way it is set-up in Honeybee) will be calculated based on lighting schedule. If you want to see the effect of light-shelf in electric lighting energy you have to run and annual daylight analysis and use the generated schedule to overwrite lighting schedule in energy simulation.


Thanks Mostafa,

I had used the lighting schedule of annual daylight simulation, but when I changed the count of sensor points, nothing changed in results. I think it shows that something was wrong.