Question

Photovoltaic cells ________.

A) require an outside source of electricity to generate electricity on their own
B) have small rotational generators built into every cell
C) rely on the electrical current produced when silicon is struck by sunlight
D) are increasingly costly produce which precludes major commercial application
E) are the major form of renewable energy produced in the U.S.

Answer 1

Photovoltaic cells produce electricity when sunlight strikes silicon within them, generating a current. They often output about 0.5 V and the current depends on the amount of sunlight. This technology enables the use of solar energy for powering small devices to large-scale electricity production.

Step-by-step explanation:

Photovoltaic cells rely on the electrical current produced when silicon is struck by sunlight. These cells, often made from pure silicon, can come in the form of single-crystal silicon, or as a thin film deposited on glass or metal. When sunlight hits the cells, semiconducting materials within them produce free electrons, which generate a current.

In terms of output, most single solar cells provide about 0.5 V. The actual current produced is directly related to the insolation, which is the amount of sunlight falling on the cell. For instance, under optimal conditions such as bright noon sunlight, a cell might yield around 100 mA/cm² of surface area. Through arrangements into panels and arrays, photovoltaic technology can power anything from small devices to residential homes or even large-scale electricity grids.

While photovoltaics are a way to harness solar energy, it's important to note they are just one method. Solar power can also be used for heating, which differs from the direct electricity generation that PV cells provide.