No, it cannot. We understand your expectations for the product's performance, but it is a common phenomenon in the solar panel industry that the actual power output does not reach the rated value. The reasons are as follows:
Firstly, the rated power is measured under standard test conditions, usually tested under ideal sunlight intensity, temperature, and angle conditions (the rated power of solar panels is typically measured under standard test conditions (STC), which is power measured under conditions of 1000W/m² of light intensity, 25℃ temperature, and vertical sun angle).
However, factors such as actual installation environment, sunlight intensity, temperature, and shading can affect the power output of solar panels. These conditions may not be fully met, resulting in actual output power lower than the rated power. Therefore, under optimal conditions, the actual power output of a 400W solar panel would be around 300-320W (about 75%-80%).