Online calculator
Photovoltaic Calculator
Calculate annual yield, self-consumption, feed-in, annual benefit and rough payback period of your solar PV system.
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What does this calculator do?
Use this photovoltaic calculator to roughly estimate how much electricity a PV system can generate per year, how much of that energy is used on site, how much is fed into the grid and how long the investment may take to pay back. It is intended as an initial planning and comparison tool for residential rooftop solar projects and similar small-scale installations.
Formula
Annual yield = System size in kWp × specific yield in kWh per kWp Self-consumed electricity in kWh = Annual yield × self-consumption share Feed-in in kWh = Annual yield − self-consumed electricity Gross annual benefit = (Self-consumed electricity × electricity price) + (Feed-in × feed-in tariff) Net annual benefit = Gross annual benefit − annual maintenance cost Payback period = Investment cost ÷ net annual benefit
Example
Example: A 10 kWp PV system with a specific yield of 1,000 kWh per kWp produces 10,000 kWh per year. With a self-consumption share of 35%, 3,500 kWh are used on site and 6,500 kWh are fed into the grid. At an electricity price of €0.32 and a feed-in tariff of €0.08, the gross annual benefit is €1,640. With an investment cost of €16,000 and annual maintenance equal to 1% of the investment, net annual benefit is about €1,480. The rough payback period is around 10.8 years.
What does this photovoltaic calculator calculate?
The calculator estimates annual solar yield, electricity used on site, electricity fed into the grid, annual financial benefit and a rough payback period. This allows you to compare different system sizes, price assumptions and self-consumption scenarios quickly.
Who is this calculator for?
It is primarily useful for homeowners and private users who want an initial estimate of whether a solar system could make economic sense. It can also help compare installer quotes or different planning assumptions.
Which inputs matter most?
The most important inputs are system size in kWp, specific annual yield and self-consumption share. Specific yield depends on location, roof pitch, orientation, shading and technical setup. Self-consumption often rises if electricity is used during the day or if a battery is installed.
How realistic is the payback period?
The payback period shown here is only a rough estimate. Real-world economics also depend on installation cost, financing, insurance, maintenance, battery storage, tax treatment, feed-in conditions and future electricity price developments.
Why is photovoltaic content strong for SEO and users?
Solar topics combine strong information intent with commercial intent. Users often search for yield, economics, self-consumption, roof size, costs and payback. That makes a high-quality calculator page especially valuable when it also includes explanations, examples, FAQs and relevant internal links.
Frequently asked questions
How much electricity does 1 kWp of solar produce per year?
A rough rule of thumb is often around 900 to 1,100 kWh per kWp per year, but the real number depends on location, roof orientation, shading, pitch and system quality.
When does a photovoltaic system pay off?
That mainly depends on installation cost, self-consumption, electricity price and feed-in tariff. The more solar electricity you use yourself, the more attractive the project often becomes.
What is a good self-consumption share?
A higher self-consumption share usually improves economics because electricity used on site is often worth more than electricity exported to the grid. A good value depends on the household load profile and whether a battery is used.
Does this calculator include batteries?
Not in detail. A battery can increase self-consumption, but it also adds cost. For realistic project economics, the battery should be evaluated separately.
Are subsidies or taxes included?
No, not individually. Grants, tax treatment, financing costs and regional details are not fully included in this simplified calculator.
Are the results binding?
No. This calculator is for general information and initial guidance only. For a real project, you should compare offers and, if needed, seek professional advice.