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Solar Calculator

For help using this calculator please read thought our detailed instructions.

Calculation Type Description Units
Estimated Watt demand
3 Total Watts Per Hour (DC) DC Amps x 12 Watts
Hours per day
6 Hours Equip is expected to run (24hr) as per application Hrs d-1
Watt-Hours per day
9 Total daily usage Watts x Hours Watt-Hrs d-1
Amp-hour calculation
10 Total watts Daily requirements Watt-Hrs d-1
11 Corrected for battery losses Assumes static average loss Watt-Hrs d-1
12 System voltage DC voltage only Volts
13 Amp-hours per day Watts divided by Volts Amp-Hrs d-1
Battery bank calculation
14 # of days backup power required Average 24 hour periods days
15 Amp-hour storage Raw capacity you need Amp-Hrs
16 Depth of discharge Assumes 50% fraction (enter decimal) 0.5
17 Required amp backup Prevents excessive discharge Amp-Hrs
18 Battery Amp Rating (20 hr) Battery Capacity in Amps fraction
19 Actual # batteries wired in parallel Raw number number
20 Batteries wired in series Relates to system voltage number
21 Rounded number of Batteries Always rounded up number
Solar Panel Array calculation
22 Sun hours per day (Direct only) Be realistic! Hrs
23 Worst-weather multiplier* 1.55 default fraction 1.55
24 Total sun hours per day Assumes average sun Amp-Hrs
25 Select panel size (Watt rating) Watt hour rating Watts
26 Nominal Panel Voltage Approximate Solar output Volts 16
27 Amps required from solar panels Total daily consumption Amps 15
28 Peak amperage of solar panel Watts divided by Volts Amps
29 Number of solar panels in parallel Raw Number number
30 Number of panels in series (12 V) it is 1 for 12v, 2 for 24v, etc number
31 Rounded number of solar panels Always rounded up number
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