Solar panel maintenance in the Algarve: what it covers, how often, and what it costs

A solar system that has stopped is easy to spot: the app goes quiet, the inverter shows a red light, the bill jumps. A system that is still running but producing less than it should is much harder to spot, and that is the one that costs money month after month. Most of what follows is about catching that second kind.

What actually holds a system back

Panels have no moving parts, so there is not much to wear out. The problems we run into are usually one of these:

• Dirt on the glass. Dust and pollen, and near the coast a thin film of salt. Winter rain washes some of it off, but the Algarve has long dry spells, and rain only partly cleans a roof. Bird droppings are worse, because they shade part of a panel and that can cut its output by much more than the size of the spot suggests.
• New shade. A tree that has grown since the installation, a new aerial, a neighbour’s extension. Shade on part of one string can drag down every panel in that string.
• Monitoring that has gone offline. Very often the inverter has simply lost its Wi-Fi, for example after the router was replaced. The system keeps producing and feeding the house, but nobody is looking at the numbers any more.
• A real fault. A loose connector, an inverter warning that nobody has read, a protection device that has tripped. A genuine fault tends to show up as a sudden drop, while dirt shows up as a slow slide that you stop noticing.
• Battery settings. A battery sitting at 10 percent is often doing exactly what it was told to, because the reserve level is set there. Temperature extremes can also pause charging.

What a maintenance visit covers

When one of our engineers visits, the job is a proper inspection of the whole installation: performance checks on the panels, the inverter, the batteries, the protection boxes and the cabling, plus safety checks on more than 100 points. Afterwards you get a short written summary of what was found, what was done and anything to keep an eye on. That document is useful later, if you ever need to make a warranty claim or sell the house.

How often

We recommend a checkup of the whole system every year. Cleaning is a separate job, and how often it pays off depends on where you live: near the sea or in a dusty area the glass gets dirty faster.

Five checks you can do yourself in two minutes

1. Compare with the same month last year, not with last month. Weather changes too much from one month to the next. A drop against the same month a year ago is worth a call.
2. Look at the inverter. Green is normal. Orange or blinking usually means a warning, red means the unit has stopped. Write down the colour, the blink pattern and any code on the screen, or take a photo. That alone often tells us which part to bring.
3. App showing no data? Check that the router is on and still has the same network name as when the system was installed. Restart the router first, then the inverter’s Wi-Fi stick. The system keeps working in the meantime.
4. System not back after a power cut? After an outage the inverter waits for a stable grid signal, which can take a few minutes. If a breaker tripped during the cut it will not restart until you reset it. Check the AC and DC breakers and the isolator next to the inverter.
5. Battery not charging or discharging? Look at the reserve level and any time-of-use schedule in the app, and check that the battery’s isolation switch has not been turned off.

What not to do

• Do not go up on the roof to clean or inspect. A fall is a far bigger risk than a dirty panel, and walking on panels can crack the cells.
• Do not use aggressive or abrasive products on the glass. Plain water with a little soap is fine. For the best result, professional cleaning with osmosis water keeps the panels producing better.
• Do not open the inverter or touch the DC cabling. The panels produce voltage whenever there is light.
• If there is a burning smell, water getting in, or the system has stopped completely, switch it off at the AC isolator if it is safe to reach and call us.

What it costs

These are our current prices, VAT included.

• Cleaning: €12.30 per panel, for the whole array. A 12-panel system is €147.60, 20 panels is €246, 30 panels is €369.
• Diagnostic visit: €183.27 for the first hour on site, then €104.55 per hour.
• Yearly preventive maintenance contract: €246 a year (€200 plus VAT). It includes one full maintenance visit with the checks above, unlimited remote support, 50% off the diagnostic visits that follow (€91.64 for the first hour, then €52.28 per hour), and 15% off parts, labour and system extensions.

If all you want is clean panels, you do not need the contract. It makes sense if you want the yearly check on a schedule and someone to call when the app looks wrong.

Systems we did not install

We look after systems of any brand and any installer, not only our own. Sharp, KOSTAL, SMA, BYD and LG are the ones we install and know best. If you are not sure what you have, send us a photo of the label on the inverter. There is more on how that works in our guide for systems installed by another company.

To book a visit or ask a question, use the request form on our service and maintenance page, or call +351 914 460 215 (Monday to Friday, 9:00 to 17:00).