Have you heard of Swanson’s Law. It is similar to Moore’s law but for solar cells. It says that every time global capacity doubles that prices drop by 20%. It is what is known as a virtuous cycle. As you purchase new solar modules this increases demand which puts pressure on manufacturers to increase production. As they increase production prices fall and this further increases demand and the cycle repeats and reinforces.
Now solar cells are a decreasing component of the overall cost as labor, installation, financing, and administration are still relatively fixed. However, the highly competitive nature of the industry continues to encourage all players to keep increasing efficiency. Look to the SunShot initiative to learn more about how the industry is trying to keep lowering prices for everyone.