PVGIS Solar Energy Production Calculator
Estimate the annual energy production of your photovoltaic (PV) system using key parameters often found in PVGIS reports.
The nominal power of your solar panel array under Standard Test Conditions (STC).
The total solar energy received on your tilted solar panels over a year. This value is specific to your location, panel tilt, and azimuth, and can be obtained from tools like the official PVGIS website.
Accounts for various losses in the system, including temperature effects, shading, wiring, inverter efficiency, and dust. A typical value is 10-20%.
Estimated Results:
Enter values and click 'Calculate' to see your solar energy estimates.
Understanding Your Solar Potential with the PVGIS Calculator
The Photovoltaic Geographical Information System (PVGIS) is a powerful tool developed by the European Commission that provides free and open access to solar radiation and photovoltaic system performance data for locations across Europe, Africa, and parts of Asia and America. While the official PVGIS website offers detailed simulations, our simplified PVGIS Calculator helps you quickly estimate your solar energy production based on key parameters.
What is PVGIS and Why is it Important?
PVGIS helps individuals, businesses, and researchers assess the solar energy potential of a specific site. It uses historical weather data and advanced models to calculate how much solar radiation reaches a given location and how much electricity a solar PV system might generate. This information is crucial for:
- Feasibility Studies: Determining if solar power is viable for a particular site.
- System Sizing: Estimating the required size of a PV system to meet energy demands.
- Financial Planning: Projecting energy savings and return on investment.
- Optimizing Design: Understanding the impact of panel tilt and orientation.
How Our PVGIS Calculator Works
Our calculator simplifies the complex PVGIS methodology to provide a quick estimate. It relies on three primary inputs:
1. Peak Power of PV System (kWp)
This refers to the nominal power output of your solar panel array under Standard Test Conditions (STC). STC assumes a panel temperature of 25°C and a solar irradiance of 1,000 W/m². For example, a 5 kWp system means your panels are rated to produce 5 kilowatts of power under ideal conditions. This is a fundamental measure of your system's capacity.
2. Annual Global Tilted Irradiation (GII) (kWh/m²/year)
The GII is perhaps the most critical input for this calculator. It represents the total amount of solar energy (in kilowatt-hours per square meter) that falls on your solar panels over an entire year, taking into account their specific tilt angle and azimuth (orientation). Unlike Global Horizontal Irradiation (GHI), which measures radiation on a flat surface, GII is tailored to your panel's actual setup. You can obtain this precise value for your specific location, tilt, and azimuth directly from the official PVGIS website or other reputable solar radiation databases. For instance, a GII of 1600 kWh/m²/year indicates a good solar resource for a well-oriented system.
3. System Loss Percentage (%)
No solar PV system operates at 100% efficiency all the time. Various factors contribute to energy losses throughout the year. This percentage accounts for:
- Temperature Losses: Panels become less efficient as their temperature rises above 25°C.
- Shading Losses: Obstructions like trees or buildings can reduce output.
- Wiring Losses: Energy lost as electricity travels through cables.
- Inverter Efficiency: The inverter converts DC power from panels to AC power for your home, with some energy loss in the process.
- Soiling/Dust: Accumulation of dirt, dust, or snow on panels.
- Mismatch Losses: Slight differences in performance between individual panels.
A typical system loss percentage ranges from 10% to 20%. For example, a 14% system loss means that 14% of the theoretically available energy is lost before it reaches your home.
Understanding the Results
Our calculator provides three key outputs to help you understand your system's performance:
Estimated Annual Energy Production (kWh/year)
This is the total amount of electricity your solar PV system is estimated to generate over a year, measured in kilowatt-hours. This value is crucial for calculating your potential energy savings and environmental impact. For example, a 5 kWp system with a GII of 1600 kWh/m²/year and 14% system losses might produce around 6880 kWh annually.
Specific Yield (kWh/kWp/year)
Specific yield indicates how many kilowatt-hours of electricity your system produces per kilowatt-peak of installed capacity per year. It's a useful metric for comparing the performance of different solar systems, regardless of their size. A higher specific yield indicates a more efficient system or a better solar resource at the location. For the example above, the specific yield would be 1376 kWh/kWp/year.
Estimated Performance Ratio (PR) (%)
The Performance Ratio is a quality indicator for a PV system. It compares the actual energy output of the system to its theoretical maximum output under ideal conditions. A PR of 100% would mean no losses, which is impossible. In our simplified model, the PR directly reflects the system loss factor. A PR of 80% means that 80% of the theoretically available energy is converted into usable electricity after accounting for all system losses. A higher PR indicates a more efficient and well-maintained system.
Disclaimer
This calculator provides an estimation based on simplified formulas and user-provided inputs. For precise and detailed solar energy production forecasts, especially for critical planning or financial decisions, it is highly recommended to use the official PVGIS tool or consult with a professional solar energy expert who can conduct a thorough site assessment.