Set a cooling power depending on outdoor temperature on EnergyPlus

edit

Hi everyone and thanks for this very usefull website .

My problem is simple, i would like to set a cooling power on a zone in EnergyPlus , depending on outdoor temperature with a linear variation between the two values. The idea is to modelize the effect of a earth-to-air heat exchanger which i have already the features.

Do i have to set a HVAC System?

i'm a beginner in this field so I don't know if there is a simple way for doing this. :)

Thank you all .