What is the purpose of photovoltaic cells?

Photovoltaic cells are specifically designed to convert sunlight directly into electricity through the photovoltaic effect. When sunlight strikes the surface of these cells, it excites electrons in the semiconductor material, creating a flow of electric current. This process allows for the direct harnessing of solar energy, making photovoltaic cells a crucial component of solar panels used in renewable energy systems.

The other options represent different energy technologies; for instance, heating water directly relates to solar thermal systems, which use sunlight to increase the temperature of water rather than generating electricity. Similarly, collecting wind energy pertains to wind turbines, which convert kinetic energy from the wind into electrical power. Storing solar energy refers to battery technologies that can store electricity generated by solar systems for later use, but does not involve the conversion process of photovoltaic cells themselves. Thus, the primary purpose of photovoltaic cells remains their function in transforming sunlight into usable electrical energy.