How to choose the best solar panels

• If the roof has less than 20-25 m² available, prioritise high-efficiency panels: each extra efficiency point can mean 10-15 Wp more per panel, which makes a real difference to total output.

• Demand a 25- or 30-year performance warranty: the best panels guarantee they'll keep at least 80-85% of their initial output after that period.

• Back contact technology (including HIBC) places the electrical contacts on the back of the panel, reducing losses from partial shading and improving performance in low-radiation conditions, which is especially relevant in northern Spain or on roofs with obstacles.

• For installations on pergolas, canopies or areas exposed to extreme weather, opt for double-glass panels: they offer greater resistance to impact and adverse environmental conditions, with warranties of up to 30 years.

• Size the installation according to your real annual consumption: an average home in Spain uses between 3,500 and 5,000 kWh/year, which equates to 6 to 10 panels of 400-450 Wp depending on the area. Installing more doesn't always translate into greater savings without a storage system.

• Consider the All Black design if the installation is visible from the street or forms part of an architectural feature: beyond aesthetics, the back contact technology that makes it possible also brings performance benefits.

• Check the installer's and product's certifications: look for IEC 61215 and IEC 61730 certifications on the panels, which are the international safety and performance standards.

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