Sizing considerations for remote off-grid systems — any unique aspects?

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Understanding Peak Sun Hours Peak sun hours (PSH) are critical in sizing a solar array for remote off-grid systems. PSH represents the average number of hours a location receives full sun per day. For example, a location with 5 PSH per day requires a larger solar array to generate the same amount of energy as a location with 7 PSH per day. System designers should consult a solar irradiance map or consult with a local expert to determine the PSH for their specific location. As a general rule, a minimum of 4-5 PSH per day is recommended for off-grid systems.
Charge Controller Sizing Considerations Charge controller sizing is equally important as the solar array and battery bank. A properly sized charge controller ensures that the solar array can safely discharge into the battery bank without overcharging or undercharging. A common rule of thumb is to size the charge controller to 10-20% of the maximum system voltage. For example, if the system voltage is 24V, a 2.4-4.8A charge controller would be suitable. However, this can be adjusted based on the specific system requirements and the type of charge controller being used.
Battery Bank Sizing Battery bank sizing is also critical in off-grid systems. A well-sized battery bank allows the system to store excess energy generated by the solar array during the day for use during periods of low sunlight or at night. A general rule of thumb is to size the battery bank to 5-10 days of backup power. For example, if the system has a daily energy demand of 200Wh, a 1-2kWh battery bank would be suitable.