How To Size Your Off-Grid Solar Power System
Small systems, such as those on an RV or boat, should use 12V systems, while larger solar arrays do best with 24V. A good rule of thumb is that if your energy needs are less
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.
20 foot containers can expand from 3,000W of solar up to 6,000W. 40 foot containers can expand from 3,000W up to 12,000W of solar in the future. We love the strategically placed solar panels on top of the container roof - we've accomplished this secure mounting with our field tested RPS Scalable Ground Mount.
That means you need a solar array rated at around 365 watts to meet your needs reliably. Next, choose your panel type. Panels come in various sizes and wattages. Here are the most common options: Once you've selected a panel size, divide your required array size by the panel wattage to find the quantity.
Now that you know your daily energy use and sun hours, it's time to calculate how large your solar array needs to be. Formula: Total Daily Use (Wh) ÷ Sun Hours × 1.25 = Solar Array Size (W) The “× 1.25” accounts for system inefficiencies (inverter losses, shading, panel age, etc.) Example: 1,460 ÷ 5 × 1.25 = 365W
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