Beginner''s Guide: Sizing Your Off-Grid Solar System
Learn how to accurately size your solar system with this comprehensive guide. Determine the panels, batteries, controller, and inverter required for your setup. Calculate load sizing, solar
Learn how to accurately size your solar system with this comprehensive guide. Determine the panels, batteries, controller, and inverter required for your setup. Calculate load sizing, solar
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Required Power of Solar Panel (without considering controller and inverter loss) = 6850 Watt-Hours/4 Hours = 1712.15 Watts. We will want to use the MPPT Controller since this is a high wattage system and want to minimize loss. We will also be using an inverter since the items are AC.
Assume we are installing a 24V solar system. We need to keep this in mind to size the battery and pick our inverter. Now, when considering the battery size, you'll need to divide the total consumption by the system voltage, in this case, 24V, and then double the result. Battery Capacity = (6850 Watt-Hours/24 Volts) * 2 = 570.83 AH at 24V.
You can check the controller specification sheet to see the wattages they can handle. For example, a 30 Amp Controller can handle 400W on 12V, so you know you can have up to 400 Watts on there. *If you want to size it by yourself, please reference Solar Charge Controller Types.
Now to figure out how big of an inverter we need; we have to add up the load wattages. Total Load Watts = 700 Watts + 125 Watts + 1500 Watts = 2325 Watts. In this case, a 2500 Watt inverter or higher is required. It would need to be 24 Volts. For details on how to calculate your solar power, see Renogy Solar Calculators.