How to Calculate Rooftop Area for Solar Panels (Sq Ft per kW)

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Rooftop solar panel

How to Calculate Rooftop Area for Solar Panels (Sq Ft per kW)

The installation of solar panels on terrace roofs is on the rise in India. A lot of homeowners are confused as to how to calculate rooftop area for solar panels for their home.

Homeowners are now getting the benefit of the central subsidy under PM Surya Ghar: Muft Bijli Yojana, and they are happily switching to free and cleaner energy.

If you are planning a rooftop solar system but do not know how to work out the area required and the number of solar panels needed, you will know exactly how much rooftop area your home solar plant needs.

Quick answer: Plan for about 100 sq ft (roughly 10 sq m) of shadow-free roof for every 1 kW of solar. So a 1 kW system needs about 100 sq ft, a 3 kW system about 300 sq ft and a 5 kW system about 500 sq ft. The panels themselves cover only about half of that space. The rest goes to row spacing, walkways for cleaning and clearance from the parapet and water tank.

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How to Calculate Solar Panel Requirement for Your Home?

Finding the exact solar panel size for your home takes a simple four-step calculation based on your electricity use.

Go through your last 12 months’ electricity bills and note the units (kWh) consumed each month.
Add up the total units for the 12 months and divide by 12 to get your average monthly consumption in kWh. This is the starting point for sizing your system.
Divide your average monthly consumption by the monthly generation of a 1 kW solar system. In India, a 1 kW solar panel system generates about 4 units a day on average (4 to 5 units on a clear sunny day), which is about 120 units a month. This gives you the total solar system capacity you need in kilowatts.
Divide that capacity by the wattage of one solar panel, usually 550 watts or 600 watts, and round up. This gives you the number of panels needed for your rooftop installation.

For example, Amit’s electricity use over the last 12 months was 450 + 400 + 400 + 400 + 450 + 500 + 550 + 500 + 450 + 400 + 350 + 450 = 5,200 units.

So his average monthly consumption is about 433 units. Dividing 433 by 120 units per kW gives a system size of about 3.6 kW.

With 550-watt panels, Amit needs 7 solar panels for home; with 600-watt panels, he needs 6.

This step-by-step approach gives you the right solar system size, so you get the most savings for your money invested.

How to find out the total Rooftop Area Required to install the Solar Panels?

In India, we know that one solar panel encompasses a standard surface area of approximately 20.86 sq. feet. To determine the total rooftop area to install a residential solar power system, we need to multiply the surface area of 1 solar panel by the total number of panels needed for Amit’s house. It is important to note that this area should receive a minimum of 5 hours of direct sunlight, which means this area needs to be a shadow-free area.

So, Amit’s house will need a total rooftop Area of 125.16 sq. ft. or 146.02 sq. ft. (20.86 sq. ft. X 6 Panels or 20.86 sq. ft. X 7 Panels)

With government incentives and with the best solar energy manufacturing companies like JAKSON Solar in the market, solar panels for houses are now affordable.

For more information:
Call JAKSON Solar Experts at: 1800-103-2600 (Toll Free)
OR
Email at: solar-bu@jakson.com