This is a graph showing the immediate increase in a PV system maintained by Solar South West's yield after being cleaned.

Solar panel servicing

Annual comprehensive O&M (operations and maintenance) plans are to be expected with large solar farms or commercial PV systems, but have you considered servicing your home’s solar panel system?

Large solar PV systems benefit greatly from consistent O&M. Regular PV servicing ensures correct operation at full capacity, achieving the highest possible rate of return. On top of this, O&M protects the asset by finding and remedying potentially damaging faults before they can cause problems.

What is perhaps often overlooked is the benefit of servicing your domestic solar panel system, but is it any less rewarding?

Contact Solar South West for a PV service quote

Solar South West provide maintenance for solar PV systems all over Somerset, Devon Dorset, Cornwall, Bristol and across the UK – but the vast majority of these maintenance plans are for commercial solar systems.

We frequently receive enquiries from property owners, interested in solar panel servicing, after the solar panels on the roof of their home have gone offline due to damage or ware and tear. This can often mean expensive repairs/replacements, but could the damage have been avoided?

Often, the damaged system has been installed many years previously, and never been serviced. Not only has this caused the PV system to develop the fault which has led to the call out – with the amount of dirt which builds up on some panels, it’s a miracle they’re generating any energy at all.

Bird droppings on modules in need of solar panel servicing
Solar panel servicing for some modules covered in dirt
mid clean for these solar panels being serviced

What is the cause of degradation and faults?

Photovoltaic modules, and the corresponding system which makes the generated solar power available in your house, have up to 1000V of energy present at any one time. This amount of electricity will cause components in your system to deteriorate over differing lifetime service expectancies.

Deteriorating or under performing components will likely cause one of two problems within your solar system: hotspots, or DC arcing. Both, if left, can seriously damage your PV system – leading to repairs beyond the original faulty component. The latter can potentially also cause PV fires.

Damage to a PV module as a result of a hotspot in the panel - could have been avoided via solar panel servicing

An unchecked hotspot burning through a PV module.

Melted component as a result of DC arcing, solar panel servicing could have prevented this

A melted component as a result of DC arcing.

Both hotspots and DC arcing can also be caused, or accelerated, by other factors such as shading, microcracks, dirt and bird droppings on the PV modules, rodent damage to cabling and poor installation.

Put simply, faults in your PV system are to be expected over time. These faults are often simple and inexpensive to remedy so long as they are identified quickly. Left for a longer period, they can lead to expensive repairs.

Benefits of solar panel servicing

1. Avoiding faults and preventing damage

Image of a hotspot, captured using a thermal camera before any significant damage could occur.

Solar panel servicing will ensure any natural deterioration within the system is identified and rectified before more extensive damage can occur, preventing expensive system repairs and hazardous faults.

On top of this, PV servicing will prevent losses and damage due to external factors such as shading and dirt; via module cleaning, system inspections and shading management.

This form of preventative maintenance will prove much more cost-effective than reacting to faults after they have already caused problems, and we can guarantee at some point – problems will occur.

What’s included in a Domestic PV service with Solar South West

2. Cost savings of PV servicing

Besides keeping your system healthy and your investment safe, there are actually cost saving benefits to servicing your PV. Inverter servicing and module cleaning will prevent the amount of solar power generated by your system from slipping below what it should be.

The two graphs below show the immediate improvement in yield after a PV clean at a site we maintain. The blue line represents the systems performance. The black line is the average trend line over the two-week period, and the filled section represents the average performance before and after the clean.

  • Graph showing immediate and obvious yield improvements after cleaningAverage PV performance ratio before cleaning: 79% Average performance ratio after cleaning: 86%
  • Second graph, showing again the immediate benefit to the same PV system the previous yearAverage PV performance ratio before cleaning: 77%. Average performance ratio after cleaning: 84%

For the average 4kW domestic PV system, the optimum annual generation figure lies somewhere in the region of 3600kWh. However, by neglecting servicing and maintenance, that figure can fall by up to 30% as a result of the combined effect of dirt, shading and inefficiency.

The annual cost of PV servicing for an average household solar system with Solar South West is c.£100 (subject to individual system specifications). 30% of 3600kWh (1080kWh) translates to £172.08 at £0.16/kWh. So in other words, the increase in generation as result of servicing – and thus the money you save on your energy bill – outweighs the cost of annual maintenance for the system.

3. Warranty terms

Not only will servicing your solar system ensure it doesn’t suffer serious damage, you will keep on track with the terms and conditions of expensive component warranties.

The costliest part of any PV system will be the PV panels themselves and the inverter(s). Most modules and inverters come with a ‘guarantee’, which ensures functionality, and that performance meets the defined standards.

Under these warranties, you will be able to send back your faulty modules or inverter(s) within the warranty period (usually around 5 years, subject to manufacturer) free of charge – but only if your system has been regularly serviced.

Guaranteed performance promise warranties will only stand if your PV installation has been regularly serviced, cleaned and maintained.

Is PV servicing worth it?

Obviously, annual servicing of your domestic PV system can seem, and is, less vital than O&M contracts at big solar farms. Much less will go wrong, and the costs are much lower than with a large PV array.

On top of that, it is not guaranteed to be cost effective. For example, if your system is suffering from only 5% losses, you will make savings of c.£28.80pa – less than the cost of the service.

However, service plans for domestic household solar systems are tailor made, and will be representative of the cost and the works needed. It is much simpler to perform a health check on a 4kW PV system than a 4MW system, and as such, the costs are much less too.

At Solar South West, we believe the security and peace of mind you obtain vastly outweighs the cost of servicing – even without any cost savings.

Faults in your PV system can be extremely damaging and expensive if left. On top of that, they can pose a serious hazard and safety threat. Not only will you be made aware of these faults before they pose a threat, you will also benefit from free replacements for expensive components within warranty.

So in order to ensure your investment in renewable solar power was worth while, and not a potential nightmare waiting to happen, servicing really is a must.