There are several reasons why the efficiency of solar panels may be low, including: 1, Shading or Obstructions: If a portion of a solar panel is shaded by trees, buildings, or other objects, it can greatly reduce the efficiency of the entire panel. 2, Poor Installation Angle: Solar panels are designed to receive direct sunlight, so it's important to install them at the proper angle to maximize their exposure to the sun. If the panels are not installed at the optimal angle, their efficiency will be reduced. 3, Dirt and Debris: Dirt, dust, and other debris can accumulate on the surface of the solar panels, reducing their ability to receive and convert sunlight into electricity. Regular cleaning can help to keep the panels functioning at their highest efficiency 4, Panel Age: Over time, the efficiency of solar panels can decline as they age. The rate at which this occurs depends on the quality of the panels, the environment they are exposed to, and other factors. 5, Poor Quality Panels: Some solar panels are made with lower-quality materials or components that are less efficient at converting sunlight into electricity. Choosing high-quality, reputable solar panels can help to ensure that your panels are functioning at their highest efficiency. By addressing these factors and choosing high-quality solar panels, you can help to maximize the efficiency of your solar energy system and ensure that you are getting the most value from your investment.