Include air infiltration of buildings
Today if 'No Ventilation' option is selected air_exch=0
https://gitlab.cern.ch/cara/cara/-/blob/master/cara/apps/calculator/model_generator.py#L185
This is conservative in terms of Pi.
Although, in reality there is always air coming in from the façade (so called air infiltration), especially during winter. The bldgs. are not "pressure vessels". The average value ranges from 0.01 to 0.5 ACH. To be more sound from a physical point of view, I propose 0.25 during winter and keep 0 during summer.
I suggest to the following:
elif self.ventilation_type == "no_ventilation":
if self.event_month[:3] = ["January", "February", "March", "October", "November", "December"]
ventilation = models.AirChange(active=always_on, air_exch=0.25)
else
ventilation = models.AirChange(active=always_on, air_exch=0.)
Update: It should specified upstream in the code to have a "minimal ACH" = 0.25 every time today it is = 0