Calculation Formula for Solar Panel and Battery Configuration

Step 1: Calculate Daily Energy Needs

Before investing in solar panels and batteries, determine your daily energy consumption.

How to Calculate:

1. List your appliances and devices: Record the wattage of each item you plan to power with solar energy.
2. Estimate daily usage: Multiply the wattage of each appliance by the number of hours you use it daily.

Formula:

Example: If your daily energy consumption is 10 kWh:

Step 2: Determine Solar Panel Output

Next, estimate how much energy your solar panels will generate daily.

How to Calculate:

1. Choose the wattage of your solar panel: Common options range from 250W to 400W.
2. Estimate hours of sunlight: This will depend on your geographic location and seasonal variations.

Formula:

Example: For a 300W panel receiving 5 hours of sunlight:

Step 3: Calculate Number of Panels Needed

With your daily energy needs and panel output determined, calculate the number of panels required.

Formula:

Example: Using 10,000 Wh daily needs and 1500 Wh output per panel:

You will need 7 panels.

Step 4: Battery Storage Calculation

Determine the appropriate battery storage to ensure you can utilize solar energy during non-sunny hours.

How to Calculate:

1. Choose the battery voltage: Common options are 12V, 24V, or 48V.
2. Calculate required battery capacity in Ah.

Formula:

Example: Using a 12V battery:

Accounting for Depth of Discharge (DoD)

Most batteries have a recommended DoD to prolong their lifespan (commonly 50% for lead-acid batteries).

Formula:

Example: If using a DoD of 50%:

Step 5: Calculate Total Battery Capacity Needed

To ensure you have enough storage, calculate the total battery capacity needed.

Formula:

Example:

If your daily energy needs are 10,000 Wh and you can use 416.67 Ah:

You will need 24 Ah of total battery capacity.

Conclusion

By following these steps, you can accurately configure a solar panel and battery system tailored to your energy needs. This not only enhances your energy independence but also contributes to a more sustainable future. If you want more information or have questions, you can contact Shielden, we can provide you with high-quality solar installations and free solar solutions.