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The TRNSYS simulation software (Transient System Simulation Program) computes the thermal behaviour of a building. For the simulations, an interior office room was assumed with one exterior surface (south) and the following dimensions and characteristics.

Basic data

  • Façade area: 14 m²
  • Module area: 8.5 m²
  • Module area with PV double façade: 14 m²
  • Module area with sunshading façade: 3.5 m²
  • Office footprint: 20 m²
  • Room height: 2.7 m
  • Room occupancy: 2 people
  • Fittings: 2 PCs including monitor, 1 copier, 1 conventional office furniture
  • Lighting: 2 office lamps
  • Usage times: 08:00–17:00 (lunch break from 12:00–13:00)


The setpoint indoor temperature during office times in the winter is assumed to be 22 °C. Outside office hours, room temperature is decreased by 4 K.

Room cooling

For the summer case, setpoint room temperature is assumed to 26 °C.

Room ventilation

Single change of air (57 m³/h) during office hours and 0.5 changes of air outside office hours. Intake air temperature derives from a heat recovery system that transfers part of the waste heat to the intake air flow.

Construction physics

In order to calculate the U-values for the surfaces surrounding the office room, the required values of the current OIB regulation were taken into account. The percentage of glass for the exterior wall of the south façade is 40%. The office unit is a medium-heavy structure.
Figure 1: Diagram of the simulated office unit

Last page update: 08.02.2011