Does a solar panel use heat or light to harvest electricity?

Solar panels primarily use light energy from the sun to generate electricity through a process called the photovoltaic effect. When light particles, known as photons, strike a solar cell, they interact with the semiconductor material used in the cell. This interaction knocks electrons loose from their atoms, creating an electrical current. The energy from the photons is directly converted into electrical energy.

On the other hand, solar thermal collectors are devices that use sunlight to heat water or air. These systems do not directly convert light into electricity and instead focus on capturing and utilizing heat energy. Solar panels and solar thermal collectors are two distinct technologies with different purposes. Solar panels are for generating electricity, while solar thermal collectors are for generating heat.

So, to answer the question, solar panels use light energy to harvest electricity, not heat.