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Solar Panel Size Equation:
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The solar panel size calculation determines the required capacity (in kW) of a solar panel system needed to meet your daily energy consumption, based on available sunlight hours and system efficiency.
The calculator uses the solar panel size equation:
Where:
Explanation: The equation calculates the solar panel size needed by accounting for your energy needs and dividing by the available solar energy (sun hours) adjusted for system losses (efficiency).
Details: Correctly sizing your solar panel system is crucial for meeting energy needs, optimizing cost, and ensuring system reliability. Undersizing leads to insufficient power, while oversizing increases unnecessary costs.
Tips: Enter your average daily energy consumption in kWh, local average sun hours per day, and system efficiency (default is 0.75). All values must be positive numbers.
Q1: What are typical sun hour values?
A: Sun hours vary by location, from 2-3 hours in northern climates to 5-6 hours in sunnier regions. Check local solar data for accurate values.
Q2: What affects system efficiency?
A: Efficiency factors include panel quality (15-22%), inverter losses (5-10%), wiring losses (1-2%), and temperature effects.
Q3: Should I add a safety margin?
A: Yes, it's common to add 10-20% to the calculated size to account for panel degradation over time and less-than-ideal conditions.
Q4: How does seasonality affect this calculation?
A: Use the lowest sun hours for your location if you want year-round reliability, or size for average if you have grid backup.
Q5: Does this account for battery storage?
A: No, this calculates the panel size needed for direct consumption. Battery systems require additional calculations for storage capacity.