pvgis calculator

PVGIS-Style Solar Calculator

Use this calculator to estimate photovoltaic (PV) output, bill savings, export value, and simple payback for a residential solar installation.

Solar Resource Region

Base specific yield in kWh per kWp per year.

Custom Specific Yield (kWh/kWp/year, optional)

System Size (kWp)

Panel Tilt (degrees)

0 = flat, 30–35 often close to optimal in many regions.

Azimuth from South (degrees)

0 = south, -90 = east, +90 = west, ±180 = north.

System Losses (%)

Shading/Soiling Losses (%)

Self-Consumption (%)

Share of solar energy used directly in your home.

Electricity Price (€/kWh)

Installed System Cost (€)

Estimated Monthly Production

Month	kWh / Month	kWh / Day

This is a planning estimate and not an official PVGIS report. For project financing or permitting, verify with site-specific simulation, shading analysis, and installer quotes.

What is a PVGIS calculator?

A PVGIS calculator helps you estimate how much electricity a solar PV system can generate at your location. The official PVGIS tools are widely used in Europe for performance modeling, but many homeowners first need a quick, easy estimator before requesting a full engineering proposal. This page gives you a practical PVGIS-style calculator to understand the economics of rooftop solar in minutes.

The main question most people want to answer is simple: “If I install solar, how much energy and money will I save each year?” To answer that, we combine your system size, your local solar resource, orientation losses, and your electricity tariff.

How this PVGIS-style calculator works

1) Start with specific yield

Specific yield is the annual energy output per installed kilowatt peak (kWp). For example, a value of 1,300 kWh/kWp/year means a 5 kWp system would produce about 6,500 kWh/year before orientation and loss adjustments.

2) Adjust for roof angle and direction

Solar panels perform best when tilt and azimuth match local sun paths. The calculator applies a penalty when:

Tilt is far from the typical optimum (often around 30° in many regions).
Panels face far from true south (in the northern hemisphere).

3) Apply real-world losses

No PV system converts sunlight perfectly. Temperature effects, inverter conversion, cables, dirt, and shading all reduce output. Entering realistic losses makes the estimate more trustworthy than a “best-case only” number.

4) Convert kWh to money

Solar value comes from two streams:

Self-consumed energy: every kWh used immediately avoids buying grid electricity at retail price.
Exported energy: excess energy is sold to the grid, usually at a lower tariff than retail.

This calculator assumes exported electricity is valued at 40% of your retail tariff. You can still get a useful first estimate, then refine with your local feed-in scheme.

Inputs explained (quick reference)

System Size (kWp): Total DC size of your PV modules.
Specific Yield: Local climate-based annual productivity.
Tilt / Azimuth: Geometry of your roof and panel orientation.
System + Shading Losses: Performance reduction from equipment and site effects.
Self-Consumption: Portion used on-site, which has the highest value.
Electricity Price: Your current retail cost per kWh.
System Cost: Installed capex used for simple payback calculation.

Interpreting your results

After clicking calculate, focus on these outputs:

Estimated annual generation: your expected AC energy in kWh/year.
Annual savings: bill reduction plus export credit.
Simple payback: system cost divided by annual savings (ignores financing and maintenance).
CO₂ reduction: rough annual emissions offset from lower grid consumption.

Simple payback is useful for screening, but lifetime cash flow is more important. In practice, include inverter replacement, module degradation, policy changes, and financing terms for final investment decisions.

Ways to improve your solar economics

Increase self-consumption

Self-consumption is usually the strongest driver of project value. You can improve it by shifting loads to daytime: EV charging, water heating, dishwashers, and laundry cycles.

Reduce shading

Small shade problems can cause disproportionate losses. Check chimneys, trees, antennas, and neighboring buildings. A professional shade survey often pays for itself.

Choose quality balance-of-system components

Efficient inverters, proper cable design, and smart monitoring reduce long-term losses and detect faults early.