Solar Panel Size Calculator – Charge Your Battery In Desired Hours
5- Divide the solar power required in peak sun hour by the charge controller efficiency (PWM: 80%; MPPT 98%). Let''s suppose you''re using a PWM charge controller. Solar power required after charge controller = 69 ÷ 80% = 86.25 watts. 6- Add 20% to the solar power required after the controller to cover up the solar panel inefficiency.