## 2 Materials and Methods
### Study Climate Zone  
As established in Directive 2024/1275 [2], EU Member States should consider outdoor climatic conditions and local specificities to promote the improvement in the energy efficiency of buildings. For the particular case of Spain, the Spanish Government defines, in the Technical Building Code (TBC) [39], six winter climate zones, with the codification \(\alpha\), A, B, C, D, E, and four summer climate zones, numerically codified as 1, 2, 3, 4. The codes,  
Figure 1: Schematic description of the method developed for the present study. 1 Data files for climate zones [34]. 2 See [35]. 3 See [36]. 4 Canary Islands Institute of Statistics [37]. 5 Catalogue of Building Elements of the Spanish Technical Building Code [38]. in both cases, are ordered from lowest to highest winter and summer climate severity, respectively. In this way, the climatic characteristics of each territory in Spain are referenced by combining a winter code with a summer code. The Canary Islands are characterised by many areas with low winter and high summer climatic severity, specifically with climatic conditions type \(\alpha 3\) (see Figure 2). The \(\alpha 3\) climate zone corresponds to sites located at an altitude below 350 metres above sea level. The Spanish TBC provides in [34], for each climate zone, a file with the extension.met, which contains the hourly mean values of different climatological parameters for a representative year. The specific data for the climate zone studied in this paper can be found in the file zonaAlfa3c.met [34]. The interpretation of the information contained in the aforementioned file is explained in [40]. This climatological information was employed by the calculation model in the different simulations performed in the present study. Table 1 contains the monthly mean values of the climatological parameters in climate zone \(\alpha 3\), calculated on the basis of the 8760 records available in [34] for the different climatological parameters. Figure 2 shows the total number of family dwellings [37] in each of the municipalities located in climate zone \(\alpha 3\). \begin{table}
\begin{tabular}{l c c c c c c c} \hline \hline \multirow{2}{*}{**Month**} & **Dry Temperature** & **Effective Sky** & **Direct Solar** & **Diffuse Solar** & **Specific** & **Relative** & **Wind** \\  & **(°C)** & **Temperature** & **Irradiance** & **Irradiance** & **Humidity** & **Humidity (\%)** & **Speed (m/s)** \\ \hline January & 17.23 & 6.31 & 105.33 & 49.14 & 0.0090 & 73.13 & 2.72 \\ February & 17.51 & 6.25 & 135.06 & 53.29 & 0.0087 & 69.55 & 2.97 \\ March & 18.46 & 7.72 & 157.32 & 66.58 & 0.0089 & 67.29 & 2.84 \\ April & 18.66 & 7.97 & 179.08 & 79.55 & 0.0095 & 70.33 & 3.03 \\ May & 20.15 & 9.55 & 200.65 & 79.42 & 0.0102 & 69.00 & 2.94 \\ June & 20.89 & 9.87 & 209.78 & 87.67 & 0.0114 & 73.53 & 2.94 \\ July & 24.21 & 13.44 & 214.96 & 80.68 & 0.0124 & 65.51 & 3.09 \\ August & 24.36 & 14.44 & 192.00 & 74.31 & 0.0128 & 67.30 & 2.88 \\ September & 22.85 & 13.72 & 149.43 & 68.02 & 0.0129 & 73.85 & 2.69 \\ October & 22.15 & 11.56 & 142.43 & 60.32 & 0.0120 & 71.85 & 2.52 \\ November & 20.12 & 9.24 & 114.02 & 50.68 & 0.0109 & 73.55 & 2.43 \\ December & 17.64 & 6.89 & 97.78 & 46.34 & 0.0100 & 79.42 & 2.62 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Average monthly climate data for climate zone \(\alpha 3\) in the Canary Islands. Note: the predominant wind direction is northeast. Figure 2: Climate zone associated with the different municipalities of the Canary Islands and number of dwellings. It should be noted that, according to the national report on the energy certification of buildings in Spain [41], 20.6% of existing buildings in Spain have the most unfavourable energy rating in terms of consumption. This problem is intensified in the particular case of the Canary Islands, where 60.6% and 52.4% of the buildings have the most unfavourable rating in terms of consumption and emissions, respectively.