The area needed for a solar panel installation is determined by various parameters, including the efficiency of the solar panels, the solar irradiation of the site, and the amount of electricity you intend to create. Here are the steps to calculating the needed area:
1. Determine Your Energy Requirements: Begin by calculating your energy requirements, which are usually expressed in kilowatt-hours (kWh) per month or year. This information can be seen on your electricity invoices. This phase is critical since it determines the size of the solar array required.
2. Determine Your Location’s Solar Irradiance: Solar irradiance is a measurement of the quantity of sunshine that falls on a specific area over a given period. The amount of electricity your solar panels can create is affected by the amount of sun irradiation in your area. This information can be obtained from local meteorological services, solar mapping software, or the National Renewable Energy Laboratory’s (NREL) solar resource maps.
3. Determine the Efficiency of Solar Panels: Solar panel efficiency varies, but a typical number is around 15-20%. The ratio of energy output to sunlight input is known as efficiency. Under ideal conditions, a 300-watt solar panel with a 15% efficiency may create 45 watts of electricity in one hour.
4. Calculate Required Solar Panel Capacity: To calculate the solar panel capacity needed, divide your annual energy consumption (in kWh) by the solar panel efficiency and the solar irradiance. Use the formula:
Required Panel Capacity (kW) = Annual Energy Consumption (kWh) / (Efficiency × Solar Irradiance)
For example, if you want to generate 10,000 kWh per year, and your panels are 15% efficient in a location with an average solar irradiance of 5 sun hours per day, the calculation would be:
Required Panel Capacity (kW) = 10,000 kWh / (0.15 × 5 sun hours/day) = 13.33 kW
5. Consider Tilt and Orientation: Solar panels are most efficient when they are inclined and orientated to face the sun as much as possible. Depending on the tilt and direction of your roof or mounting system, adjustments may be required.
6. Determine Panel Size: Solar panel sizes vary, but a common size is around 1.7 square meters (18.3 square feet) per panel. To calculate the number of panels, divide the required capacity (in kW) by the panel size (in kW). For example, if you need 13.33 kW and your panels are 0.3 kW each:
Number of Panels = 13.33 kW / 0.3 kW/panel = 44.43 panels
Round up to the nearest whole number; you would need 45 panels.
7. Calculate Total Area: To determine the total area required, multiply the number of panels by the area per panel. Using the example above, if each panel is 1.7 square meters:
Total Area = 45 panels × 1.7 square meters/panel = 76.5 square meters
So, in this example, you would need approximately 76.5 square meters of space for your solar panel installation.
Keep in mind that this is a simplified computation. Shade, panel orientation, and particular panel efficiency can all differ. It’s best to speak with a professional solar installation who can perform a site inspection and provide a more accurate quotation for your specific location and energy requirements..
