Calculadora de Potência de Painel Solar
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
kWh/dia = kWp × horas_sol × eficiência; CO₂_evitado = kWh/ano × 0,233
About this calculator
This calculator estimates the energy generated by a photovoltaic solar panel in kWh per day and the CO₂ avoided annually. Simply enter the panel power in kWp, the average daily peak sun hours in your region, and the system efficiency (considering losses from temperature, dirt, and inverter, usually between 70% and 85%). The result shows daily and annual production, as well as CO₂ emission reductions.
The calculation is straightforward: multiply the panel power (kWp) by peak sun hours and efficiency (as a decimal). For example, a 0.33 kWp panel with 5 sun hours and 80% efficiency generates 0.33 × 5 × 0.8 = 1.32 kWh/day. Multiply by 365 to get annual production. For CO₂ avoided, multiply annual production by 0.233 kg/kWh, the average emission factor of the Brazilian grid.
Use this calculator to size residential, commercial, or rural systems, compare different panels, or evaluate the environmental return of a solar investment. It is useful for those looking to reduce electricity bills and contribute to sustainability. Remember that peak sun hours vary by geographic location and season.
Important considerations: actual efficiency depends on factors like panel orientation, shading, and temperature. The CO₂ emission factor may vary by region and local energy mix. Consult a professional for a detailed project. This calculator provides an initial estimate and does not replace a complete technical study.
Frequently asked questions
What does kWp mean on a solar panel?
kWp stands for kilowatt-peak, the maximum power the panel can generate under ideal conditions of solar irradiation (1000 W/m²) and temperature (25°C).
How do I find the peak sun hours for my region?
You can consult solar irradiation data from INPE or solar atlases. Common averages in Brazil range from 4 to 6 hours per day.
Does system efficiency include inverter losses?
Yes, efficiency accounts for losses from temperature, dirt, cables, and inverter. Typical values range from 70% to 85%.
Is the CO₂ avoided calculation accurate everywhere?
The factor of 0.233 kg/kWh is a national average. In regions with a cleaner grid (e.g., hydroelectric), the actual value may be lower.
Can I use this calculator for a full system?
It estimates generation for one panel. For a system with multiple panels, multiply the result by the number of panels.