This customers 10x 445w all black (Bi-Facial) solar panels is all you need to generate 4000kwh per year. This recent installation on the Isle of Wight is exactly that and the owner is already reaping the rewards of the late summer sun. The 8kW SigEnergy battery will make the most of any excess energy and the MyEnergi EV charger will charge the car, using either excess solar or taking advantage of a smart tariff at night..