Solar Panels

Often, yes. Bifacial dual-glass panels also capture light reflected onto their rear side, so on flat roofs with a light surface, pergolas and carports they can produce several percent more energy. On a standard tiled pitched roof the panel sits close to the tiles and the rear gain is small, so a monofacial panel is usually the better value there.

Yes, if you choose the right equipment. Close to the coast we use panels certified to IEC 61701 (the salt mist corrosion test), prefer dual-glass panels, and use corrosion-resistant aluminium and stainless steel mounting. We check the certificates on each datasheet before recommending a panel for a seafront property.

You can usually add panels later if your inverter has spare capacity. It is best to match the new panels to the existing ones on the same string (similar power, voltage and current); otherwise we put them on a separate MPPT input or add a second inverter. We plan for future expansion from the start, so tell us if you expect an EV, a heat pump or a pool in the coming years.

A light clean once or twice a year is usually enough, plus an extra one after a calima, when Saharan dust settles on everything. Rain removes most normal dust, but a heavy dust layer can cut production noticeably. Never use high-pressure water or abrasive products. We offer a maintenance and cleaning service.

Yes, slightly. Every panel loses a small amount of output for each degree its cells heat up above 25 °C, which is the temperature coefficient on the datasheet (around -0.26 to -0.30% per °C for modern N-type panels). On a hot July afternoon that can mean a 5–10% dip. We reduce this by choosing panels with a low temperature coefficient and leaving ventilation space under the panels. The long sunny season more than compensates, which is why solar pays back so well here.

Quality panels typically produce electricity for 30 years or more. You get two manufacturer warranties: a product warranty against defects (typically 15–25 years, depending on the brand and model) and a performance warranty that guarantees around 87–88% of the original output after 30 years. On top of that, KiDi Solar gives a 5-year installation warranty.

It depends on your electricity use, roof space and whether you add a battery. Most homes we equip on the Costa del Sol use between 10 and 24 panels of 440–500 W, which means roughly 4.5 to 12 kW. During the free survey we size the system from your electricity bills, so you do not overpay for panels you do not need.

N-type TOPCon panels are the current standard: high efficiency, low degradation and an excellent price per watt. Back-contact panels (LONGi HPBC and AIKO ABC) move all electrical contacts to the back of the cell, so more of the front surface captures sunlight. They are usually more efficient and look cleaner, but cost a little more. Back-contact makes most sense when roof space is limited; TOPCon is the best value when space is not an issue.

Tier 1 is a list published by BloombergNEF of manufacturers whose own-brand panels have been used in large, bank-financed solar projects. It measures bankability, meaning the financial strength and track record of the manufacturer, not the quality of a specific panel. It is still a useful filter: a Tier 1 manufacturer is far more likely to be around in 25 years to honour your warranty. All brands we install are on the 2026 Tier 1 list.

All six brands we install are BloombergNEF Tier 1 manufacturers, so the right choice depends on your roof and budget rather than on one “best” brand. For maximum output from a small or complex roof we often recommend back-contact panels from LONGi or AIKO. For the best price per watt, N-type TOPCon panels from JinkoSolar, JA Solar, Trina Solar or Astronergy are excellent. After a free survey we recommend the panel that gives you the most energy for your money.