An analysis of the potential of envelope-integrated solar heating and cooling technologies for reducing energy consumption in European climates

  • Peru Elguezabal Tecnalia
  • Beñat Arregi TECNALIA Sustainable Construction Division,


There is a clear trend towards the increased contribution of renewable energy at European level, and EU policies are oriented towards that direction. The building sector is no exception and presents an urgent necessity for increasing the share of renewable energy sources (RES) to reduce the impact on the environment.

The aim of this paper is to examine the potential of solar heating and cooling technologies in reducing energy consumption by incorporating solar thermal and PV collectors within the building’s envelope. Although generally envisaged to be integrated in the roof, preferably oriented to the south, this study explores also their potential for integration into the façades.

External climate influences both the demand for space heating and cooling (influenced by temperature) and the potential from solar renewable energy (incident global irradiation). However, a time lag exists since supply and demand peak at different times within the day as well as during the year.

This study assesses the interplay of solar energy supply with heating and cooling energy demand. An analysis is performed over climate data files for five European locations, based on daily weather data. Besides the extent of incident solar irradiation, its seasonal usability is assessed with regard to the thermal demand. The impact of the inclination of solar collector devices is assessed by comparing their placement on a horizontal plane, on the inclination of maximum exposure for each climate, and on vertical planes for the four cardinal directions.

As a conclusion, the utilization of solar energy for different scenarios is assessed and a discussion on the integration of solar thermal and PV collectors over façades is presented, building on the potential of these technologies for developing innovative solutions that could significantly upgrade the buildings’ energy performance in the near future.


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How to Cite
ELGUEZABAL, Peru; ARREGI, Beñat. An analysis of the potential of envelope-integrated solar heating and cooling technologies for reducing energy consumption in European climates. Journal of Facade Design and Engineering, [S.l.], v. 6, n. 2, p. 085-094, june 2018. ISSN 2213-3038. Available at: <>. Date accessed: 18 june 2018. doi: