SOLAR PANEL SIZE

NORTHWEST POWER CO

www.nwpwr.com

1. Total average amp hours per day from the Systems Loads Sheet line   10

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2. Multiply line 1 by 1.2 to compensate for loss from battery charge/discharge

3. Average sun hours per day in your area

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4. Divide line 2 by line 3. This is the total solar array amps required.

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5. Optimum or peak amps of solar module used. See module specifications   example is (SP75 is 4.4 amps )

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6. Total number of solar modules in parallel required. Divide line 4 by 5

7. Round off to the next highest whole number.

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8. Number of modules in each series string to provide DC battery voltage:

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9. Total number of modules required: Multiply line 7 by line 8

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Also don't forget in Winter Months your Sun time is Less

so be sure your Sun time average is correct.