In LED, brightness is measured in lumens. The higher the lumens are, the brighter the light is. Watts is just the power consumption per unit time. It's not directly related to the light brightness. As for the solar street light of Watts, different lumens will have different brightness. INLUX SOLAR has always adopted super bright LED Chips. The finished Lumen efficiency of our lamps can reach up to 195lm/w, while that of normal solar lights is 130 -140lm/w.