The passive HVAC system envisioned is represented within this figure. Air would be travel through a labyrinth of pipe systems underground. The ground acts as a thermal mass to moderate air temperatures through out the year. As a result HVAC energy savings could be achieved.
This graph represents the first steps to modeling this passive HVAC system. What is shown is typical meteorological year, TMY, data for Athens, Greece [red] and calculated values of air temperatures [blue].
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