How does the solar panel calculator estimate the number of panels?

It uses your daily energy use (in kWh), the average peak sun hours for your location, the wattage of each panel, and a system loss percentage. It calculates the required array size in kW, then divides by the panel wattage to get the number of panels.

What is a typical system loss percentage?

System losses account for inefficiencies like inverter losses, wiring, shading, and temperature. A common default is 14% (or 0.86 efficiency). You can adjust this based on your specific setup.

Can I use this calculator for off-grid systems?

Yes, it works for any solar array sizing. For off-grid, you'll need to account for battery storage separately, but the panel count and array power estimate remains valid.

Экология

Мгновенно, конфиденциально и бесплатно

Калькулятор: Solar Panel.

Используйте Калькулятор: Solar Panel, чтобы получить понятный и практичный результат по введённым данным.

Этот калькулятор пока переведён не полностью — часть текста отображается на английском.

Расчёт на устройствеБез регистрации

Введите значения

Результаты обновляются во время ввода.

02 / ОТВЕТ

Daily energy use

Peak sun hours

Panel rated power

System losses

Required array power

5,88kW

Panels required

Installed array power

6kW

Estimated daily generation

20,4kWh/day

Как пользоваться

Required array power = daily energy use ÷ (peak sun hours × (1 − system-loss fraction)).

Use locally measured or sourced assumptions for sun hours and losses; no location data or tariff is included.

Cite this calculator

Canonical URL: https://mathify.one/ru/sustainability/solar-panel

Cite as: Mathify. (n.d.). Калькулятор: Solar Panel. https://mathify.one/ru/sustainability/solar-panel

Use Cases

Residential rooftop solar sizing

Homeowners can estimate how many panels they need to cover their daily electricity consumption, helping them plan a rooftop installation.

Example: If you use 30 kWh/day, have 5 sun hours, and use 400W panels with 14% losses, you'd need about 18 panels.

Small business or community project planning

Small businesses or community solar projects can quickly estimate the required array size and panel count for their energy needs.

Example: A workshop using 50 kWh/day with 4.5 sun hours and 350W panels would need around 37 panels.

Frequently Asked Questions

How does the solar panel calculator estimate the number of panels?: It uses your daily energy use (in kWh), the average peak sun hours for your location, the wattage of each panel, and a system loss percentage. It calculates the required array size in kW, then divides by the panel wattage to get the number of panels.
What is a typical system loss percentage?: System losses account for inefficiencies like inverter losses, wiring, shading, and temperature. A common default is 14% (or 0.86 efficiency). You can adjust this based on your specific setup.
Can I use this calculator for off-grid systems?: Yes, it works for any solar array sizing. For off-grid, you'll need to account for battery storage separately, but the panel count and array power estimate remains valid.

Tips & Common Mistakes

Tips

Use your average daily energy use from your electricity bill (kWh/day) for the most accurate estimate.
Find your location's average peak sun hours from a reliable solar resource map or database.
Adjust the system loss percentage based on your specific conditions; 14% is a good starting point.
Consider future energy needs (e.g., EV charging) when sizing your array.

Common Mistakes to Avoid

Using monthly energy use instead of daily – divide by 30 to get daily kWh.
Ignoring system losses, which can lead to undersizing the array.
Using panel wattage that doesn't match the actual panels you plan to install.

Last updated: August 13, 2026