How many solar panels do I need to charge a 48V 100Ah battery?
To charge a 48V 100Ah battery, you’ll need approximately 3–4 solar panels rated at 300W each, assuming 5 hours of daily sunlight and 80% system efficiency. The battery stores 4.8kWh (48V × 100Ah), requiring 6kWh/day after accounting for losses. Pro Tip: Use MPPT charge controllers to maximize energy harvest and match panel voltage to the 48V system.
What factors determine solar panel requirements?
Key factors include battery capacity, sunlight hours, panel efficiency, and system losses. For a 48V 100Ah battery (4.8kWh), accounting for 20% losses raises energy needs to 6kWh/day. With 5 peak sun hours, you’d need 1.2kW solar capacity—achievable with four 300W panels. Pro Tip: Oversize your array by 15–20% to compensate for cloudy days.
How does sunlight duration affect panel count?
Sunlight hours directly dictate energy yield. In regions with 3 hours of peak sun, six 300W panels (1.8kW total) would be needed. Conversely, areas with 6 hours require just two panels. Real-world example: A Phoenix, Arizona installation (6.5 sun hours) needs only two panels, while Seattle (3 hours) requires four. Warning: Never assume “rated” sunlight—use local irradiance maps.
RackBattery Expert Insight
FAQs
Yes, but wire two 24V panels in series to reach 48V. MPPT controllers optimize this setup better than PWM alternatives.
What if my panels produce excess energy?
Install a hybrid inverter to feed surplus to the grid or add battery expansion modules for storage.