Spain: Solar Obligation since 2006

In March 2006 the Spanish Government passed the new Technical Buildings Code (CTE). It has been the most significant reform of the country’s building sector in decades. The law covers safety, health and noise protection issues in buildings, and it deals with sustainability and energy efficiency aspects. The solar sector of the CTE includes an obligation regarding the use of solar thermal energy in all new buildings and buildings undergoing major renovation and/or changes of use. Solar energy is supposed to cover 30 to 70 % of the domestic hot water demand.

The CTE applies at the time when building construction is authorised. Therefore, it is only at the end of 2008 or in 2009 that first judgements on the impact of the law on the market can be made. The Spanish government expects between 1.050 and 1.750 MWth new solar capacity to be installed until 2010. The municipal solar obligations that exist in more than 50 cities and provinces throughout the country remain in force in case their requirements are stronger than the ones of the national law.

This article was written by Ina Röpcke, a German journalist and solar thermal expert.




Technical Building Code
in Spanish: Codigo Tecnico de la Edificacion (CTE)
(Royal Decree 314/2006)
The use of solar thermal energy is regulated in the part “Documento Basico HE - Ahorro de Energia" of the CTE.  


Obligation to cover 30 to 70 % of the domestic hot water demand with solar thermal energy  

Date when law

17 March, 2006

Date when law
came into effect  

29 September, 2006
(solar thermal section entered into force)  

Target group  

The law applies to new buildings, independent of their use, and to buildings undergoing a major renovation.  


The solar fraction depends on the:  
assumed volume of domestic hot water demand (the larger the consumption, the higher the fraction required)
back-up energy (in case of electricity, the required solar fraction is higher than in case of gas or oil back-up)
the level of solar radiation available (Spain is divided in five climatic zones. Each province or territorial unit is allocated to one of these zones.)


Exceptions are possible in case of buildings using other renewables or cogeneration.

Last review of
this tabloid  

27 August, 2008


English and Spanish text can be found via


IDAE Instituto para la Diversificación y el Ahorro de la Energía (Spanish Energy Agency)
C/Madera, 8 28004 Madrid, Spain 
Phone 0034 - 91 456 49 00  




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