An oversupply means demand for solar panels that can be produced at a profit is less than the supply of solar panels. If they can't produce the solar panels for

An oversupply means demand for solar panels that can be produced at a profit is less than the supply of solar panels. If they can't produce the solar panels for a profit, eventually the companies will be too broke to further expand supply. The supply of solar panels will sit at an equilibrium, limiting Humanity's move to solar energy. Solar panel manufacturers must continue to become more efficient every year to drive demand. An oversupply is not an economical problem - The world knows it needs much more solar energy than it is currently using. The problem is a technological one. Solar panels must use less than a certain amount of goods and services compared to existing energy sources for it to be economical for society to switch to it. You could enact a law to forbid the use of coal energy tomorrow, allowing only solar energy, but it would work as well as the Khmer Rouge forcing city dwellers onto farms - which would only result in mass starvation because city dwellers lack the skill to farm using less than a certain amount of goods and services. i.e. profitably. The technology is not there yet in terms of replacing all energy use with solar power.