Yes, you can install solar panels flat, but they will experience a degree of energy loss without the slightest inclination toward the sunlight. Although it certainly is advantageous to have a roof that is inclined in the sun's direction, a flat surface will also do. With a flat roof, your solar panels will still get direct sunlight,. Solar panels should not be flat because they can collect water, which will build up on the surface and damage the solar cells. So, it is much better to. Installing solar panels on a flat roof has upsides and downsides. They will help you determine whether the investment is worth it or not. You need planning permission for flat roof solar panels if you live in the United States. You will contact two parties: your electric company and the local building authority. It takes some. The best position for solar panels is an angle tilted toward or perpendicular to the sunlight. This is to maximize the energy that is realized from the sun. In addition, the direction the solar.