Office Building Vajra in Loulé, Portugal

Description of the application

Solar Heating and Cooling of the Head Office Building of Vajra – Solar Thermal Design and Distribution Company located in the south of Portugal, Algarve. 

General description of the system

The thermal cooling system installed is an absorption chiller (yazaki). The solar thermal system is composed by flat plate collector and a storage tank. Auxiliary heat is provided by a gas boiler.
Cooling is provided in summer months (between April and October) and heating in winter months (between November and March). The system also provides hot water preparation.

Central air-conditioning unit


closed cycle

Nominal capacity

35 kWcold

Type of closed system


Brand of chiller unit


Chilled water application

fan coils



Heat rejection system

wet open

Solar thermal

Collector type


Brand of collector


Collector area

128.8 m2 aperture

Tilt angle, orientation

30°, 15° west

Collector fluid


Typical operation temperature

88 °C driving temperature for chiller operation


Heat storage

12 m3 water

Cold storage


Auxiliary heating support

gas boiler

Use of auxiliary heating system

space heating in winter

Auxiliary chiller


System performance

No monitoring data is available.
The overall performance of the system, evaluated by the owner in terms of conventional energy reduction of consumption, is good.

System reliability and overall success of the installation

The user is a company working in solar thermal (design and commercialisation). The system is installed in its office and they are satisfied with it.

General information

Type of building  office building
Location  Loulé, Algarve, Portugal
In operation since  September 2005
System operated by  Vajra
Air-conditioned area  670 m2


Storage tank and Chiller
Caption 1
Scheme of the system
Storage tank and Chiller
Collector field
Scheme of the system

Clicking an image opens the gallery view.

Specific information

Further specific information about the system are included in the filled in technical questionnaire.


185 K


For more information on the project please feel free to contact:

Maria João Carvalho