Go green with a 20W Solar panel, 30A MPPT Charge controller, a digital time switch and a 12V 4.2W brushless pump to power your hydroponic Tower off the grid. Packed in a waterproof box, this enables you to place yourTower anywhere. The Solar panel feeds the battery, and the pump runs off the battery. The battery aims to provide 5 days of power without sunlight, because, hey, it rains sometimes, but don't have enough juice, get a larger deep cycle battery. Want to run something else? Just unplugg the timer or pump, and plug in the DC appliance you want.