Yes, you can connect a solar panel directly to a DC water pump, but it is only recommended for “direct-drive” applications where varying flow rates are acceptable. The DC/AC ratio (also called the panel-to-inverter ratio) compares the total DC wattage of your solar panels to the AC wattage rating of your inverter. For example, if you have 4,000 W of panels and a 3,000 W inverter, the ratio is: DC/AC ratio = 4000 ÷ 3000 = 1. While this step is optional, it helps store. To run a water pump on solar, multiply the pump's power by 1.