Solar XXI building

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General Information:
  • Project name: Solar XXI
  • Project type: new building
  • Building type: Office building
  • Building Typology: Non-residential
  • Location: Portugal, Lisbon District , Lisbon Municipality
  • Year of construction: 2004-2005
  • Number of buildings: 1
  • Number of floors: 3


Building Size:
  • Gross floor area: 1500 m2
  • Gross heated floor area: 1200 m2


Building Envelope:
  • Exterior wall: 22 cm brick; 6 cm ETICS; U-value = 0.45 W/(m2K)
  • Roof: 5 cm expanded polystyrene; 5 cm extruded polystyrene; U=0,26 W/(m2K)
  • Basement floor / floor slab: 10 cm expanded polystyrene; U-value=0,8 W/(m2K)
  • Windows and balcony doors: Double glazed windows; aluminum  scrolling  frame; U=3.5 W/(m2K)


Building service systems:
  • Ventilation: natural  cooling  of  the  building, with external shading devices and passive  cooling  system  using  buried  pipes.
  • Heating: Heat recovery on the inside face of photovoltaic modules assisted by a natural  gas  boiler in periods without sun.
  • Photovoltaic installation: Installed capacity of 12 kW photovoltaic  modules  on  the  south  façade (100 m2 in  line  with  windows) and 6 kW of photovoltaic modules in the parking  lot .
  • Building service systems:
Building energy performance:
  • Annual heating demand: 12 kWh/m2a
  • Cooling: 0 kWh/m2.a
  • Primary energy requirement: 2 kWh /m2a
  • Renewable energy production: 54 kWh/dia
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