Solar Maintenance & Repair Cost Estimator
Estimate the running costs of your PV system, from inverter replacement to regular cleaning, entirely in your browser.
Your inputs are processed in your browser and are not transmitted to our servers. Note: third-party resources (e.g. advertising and analytics from Google/Cloudflare) and an optional PayPal donation link may transfer data when loading or when clicked. Browser extensions or plugins may be able to read content that is visible in the input fields.
The result will appear here …
Legal notice
Current as of: 11.08.2026.
The results reflect the legal and fiscal state as of the date stated above. They are provided for general information and initial guidance only. They are not individual financial, tax or legal advice, and no guarantee is given as to their accuracy, completeness or suitability for your circumstances. In particular, the results are not a substitute for an official or judicial assessment. Please check the information independently and seek qualified advice where appropriate, as you are solely responsible for any decision made in reliance on the result.
How to use this tool (video)
This video is hosted on YouTube. When you play it, data may be sent to Google.
Solar maintenance cost estimator: plan your running costs realistically
What running costs come after a photovoltaic system is installed? Our maintenance cost calculator estimates the running operating costs over the entire life of your system. In addition to regular maintenance and cleaning, it accounts for inverter replacement, a repair reserve for unforeseen faults, such as lightning damage or defective contacts, and optionally photovoltaic insurance. The result shows the total costs, the average per year and the average per kWh, so you can plan a realistic reserve. The reference values in the calculator reflect the state of September 2026.
Where the running costs arise
Solar modules themselves need very little maintenance and typically last well over 25 years, modern cells often more than 30. The inverter is the only major wearing part: it converts the modules' direct current into usable alternating current and usually needs replacing every 10 to 15 years depending on quality and operating temperature. A replacement typically costs 1,000 to 2,500 euros depending on size. On top of that, depending on the system, occasional cleaning when heavily soiled, optional insurance and small repairs may be needed. As a rough rule of thumb, running costs amount to one to two percent of the purchase price per year; the calculator bundles all of this as running operating cost.
What "average per year" and "per kWh" mean
The average per year helps you compare operating costs with your annual savings. The average per kWh relates total costs to the electricity produced: a value around 1 cent per kWh is considered very cheap, and values of 1 to 2 cents are realistic for a system with an inverter replacement. This shows you quickly that running costs only slightly reduce a system's yield.
Sample calculation
An 8 kWp system over 25 years with 80 euros of maintenance per year, one inverter replacement (1,200 euros) after 15 years and a 500 euro repair reserve costs about 3,700 euros in total, about 148 euros per year. Based on an 8,000 kWh yield that is less than 2 cents per kWh.
Frequently asked questions
How long does an inverter last?
Usually 10 to 15 years, depending on quality and operating temperature. In a typical rooftop system, one to two replacements are due in the first 25 years. The calculator determines the number from the lifespan you choose.
Do I have to clean the modules regularly?
Not necessarily, rain cleans most modules itself. With heavy soiling, such as bird droppings or dust, occasional cleaning can improve yield. In the calculator you can set an annual amount for this or set it to zero.
Are these costs realistic?
They are a sensible planning figure based on typical experience values. Actual costs vary widely with maintenance contract, roof, region and component quality. For a precise estimate, get quotes from installers.
What is the repair reserve?
A buffer for unforeseen faults such as defective contacts, lightning damage or individual faulty modules. The default of 500 euros for the whole lifetime is conservative and adjustable.
Should I plan for photovoltaic insurance?
Optional, but useful, since a rooftop system is exposed to weather and damage. A PV insurance policy usually costs about 40 to 180 euros per year. In the calculator you can enter this amount as its own position to make your cost estimate more realistic.
Are maintenance or repairs subject to registration or taxes?
Maintenance and repair itself is not a separately registrable activity when carried out by an installer. Income tax or sales tax on your solar power follows its own rules; inform yourself through an advisor.
Are my data stored?
No. All calculations run 100 % locally in your browser. Your entries are neither sent to a server nor stored.
Read more about this tool
How the maintenance cost calculator works
The solar maintenance cost calculator is built from several parts: annual maintenance, optional cleaning, inverter replacement and a repair reserve. For the inverter the tool asks for its expected life and replacement cost, then sets aside the amounts due over the lifetime. The repair reserve covers unforeseen faults such as defective contacts or lightning damage. From the sum of all positions it derives the total cost, the average per year and the amount per kWh produced. This shows you at a glance how much running costs reduce your yield and what a realistic reserve looks like.
What maintenance really costs in Germany
For a typical 10 kWp rooftop system, running costs including insurance, metering and occasional cleaning usually come to 150 to 350 euros per year. A flat-rate service contract with an installer often costs 120 to 300 euros depending on scope and region. The modules themselves need little care, rain cleans most of them; professional cleaning is only needed when they are heavily soiled. The inverter is the largest single item: depending on quality and operating temperature it lasts 10 to 15 years, and a replacement costs about 1,000 to 2,500 euros depending on size. Optional photovoltaic insurance costs around 40 to 180 euros per year depending on the policy. As a rough rule of thumb, plan on one to two percent of the purchase price per year for operating costs. You can adjust the values in the calculator to match the quotes from your installer.
When maintenance is actually worthwhile
Solar systems are not maintenance-free, but they need little care. The most important thing to watch is output: modern inverters and monitoring apps often flag problems early, frequently without any contract. A failed inverter quickly costs several hundred euros in lost yield, so a prompt replacement pays off. A visual inspection by an installer makes sense in the first years, after severe storms and whenever output drops suddenly. You rarely need to clean modules; bird droppings and leaves can lower local output measurably though. Modules also lose only a little output as they age, roughly half a percent per year with modern cells. In most cases a moderate reserve is more realistic than an expensive full-service contract.
The calculator runs 100 % locally
All calculations run directly in your browser. Your entries never leave your device and are neither sent to a server nor stored. You can try out different scenarios freely and adjust the values at any time, without anything staying behind on your device.